Dec. 2024, Volume 18 Issue 12

Nov. 2024, Volume 18 Issue 11

With the advantages of low raw material cost and 100% atom utilization, the synthesis of high value-added chemical product cyclic carbonates by the cycloaddition of CO2 to epoxides has become one of the most prospective approaches to achieve the industrial utilization of CO2. In this paper, Ag nanoparticles loaded on polyethyleneimine (PEI)-modified UiO-66-NH2 (Ag/PEI@UiO-66-NH2) are successfully synthesized by in situ immersion reduction. The Ag nanoparticles and the amino groups on the surfaces of PEI@UiO-66-NH2 contribute to the adsorption of CO2 and polarization of C–O bonds in epoxides, thereby boosting the conversion capability for the CO2 cycloaddition reaction. This work provides a guide to designing a highly efficient catalyst for in situ capture and high-value utilization of CO2 in industrial applications. (Huiyu Fu, Jiewen Wu, Changhai Liang, Xiao Chen, Front. Chem. Sci. Eng. 2024, 18(11): 126) Download cover

Oct. 2024, Volume 18 Issue 10

We have developed a novel NiRu/SiO2 bimetallic catalyst that significantly improves the efficiency of polyethylene hydrogenolysis, a key process in chemical recycling. This advancement reduces methane production by 69% compared to traditional Ru/SiO2 catalysts and increases the yield of valuable liquid products to 83.1C%. The research, which includes temperature-programmed reduction and desorption experiments, reveals a mechanism where the Ni-Ru alloy enhances hydrogen adsorption, leading to improved product selectivity. This work represents a significant step forward in the sustainable conversion of plastic waste into useful chemicals. (Xiangkun Zhang, Bingyan Sun, Zhigang Zhao, Tan Li, Marc Mate, Kaige Wang, Front. Chem. Sci. Eng. 2024, 18(10): 110) Download cover

Sep. 2024, Volume 18 Issue 9

The catalytic and targeted oxidation of monosaccharides into valuable sugar acids is a key reaction in the synthesis of biomass-based chemicals. Herein, an activated carbon supported gold catalyst was used to oxidize glucose and xylose to gluconic acid and xylonic acid under neutral condition with a flow-through reactor. Notably, the yields of gluconic and xylonic acid reach 93% and 92%, respectively. Moreover, we also explored the reaction kinetics including activation energy and turnover frequency. Overall, we propose a feasible and efficient route for targeted production of gluconic acid and xylonic acid, which would benefit the biomass conversion techniques for valuable chemicals production. (Ziqin Gong, Zengyong Li, Xu Zeng, Fengxia Yue, Wu Lan, Chuanfu Liu, Front. Chem. Sci. Eng. 2024, 18(9): 106) Download cover

Aug. 2024, Volume 18 Issue 8

Graphene oxide (GO), as a 2-dimensional material, has shown great promise in the removal of emerging contaminants from water, yet the separation and recycling challenges have limited its practical use. To overcome these challenges, GO was first thermally reduced to form a porous nanostructured hydrogel, which was then functionalized with polydopamine (PDA). The PDA with abundant functional groups, therefore, act as both adsorption and nucleation sites for the in-situ formation of cobalt-doped ZIF-8 nano-adsorbents. More importantly, the nanosized ZIF-8 as well as its structural cobalt loading were found to affect the aerogel’s physicochemical and adsorption properties. The resulting hybrid aerogels benefit from both the high surface area and mechanical stability of reduced GO and the excellent adsorption capabilities of ZIF-8, exhibiting superior adsorption performance, mechanical stability, and recyclability and offering a sustainable solution for heavy metal removal from wastewater. This work represents a significant advancement in adsorption-based environmental remediation technology, achieving high-capacity ion adsorption and easy adsorbent recovery. (Nurul A. Mazlan, Allana Lewis, Fraz Saeed Butt, Rajakumari Krishnamoorthi, Siyu Chen, Yi Huang, Front. Chem. Sci. Eng. 2024, 18(8): 89) Download cover

Jun. 2024, Volume 18 Issue 7

Continuous CO2 emissions from the modern development of human society and industry is a significant contributor to global climate changes. CO2 capture and utilization has been considered by the society for abating CO2 emissions, which primarily involves capturing CO2 from various sources (as well as the atmosphere) and converting it to value-added chemicals/fuels (ideally using renewable energies). Nonthermal plasma (NTP) catalysis, which operates under mild conditions and is compatible with green electricity/hydrogen, is a promising technology to achieve CO2 utilization. Here, we compared the effects of catalyst pore size and active metal loading on the performance of NTP-catalyzed hydrogenation of CO2 to methanol. The findings show that the pristine siliceous mesocellular foam support with high specific surface areas and large mesopore volumes could promote plasma discharge and species diffusion across the framework. Also, the inclusion of active metal sites could stabilize the CO2/CO-related intermediates to facilitate the surface reaction towards methanol formation. (Yi Chen, Shaowei Chen, Yan Shao, Cui Quan, Ningbo Gao, Xiaolei Fan, Huanhao Chen, Front. Chem. Sci. Eng. 2024, 18(7): 77) Download cover

Jun. 2024, Volume 18 Issue 6

In this study, novel perovskite-type oxygen transport membranes were designed and synthesised by a scalable reverse co-precipitation. The substitution of Cu2+ and Zn2+ for partial Fe3+ in La0.7Ca0.3Co0.3Fe0.7O3–δ led to the generation of additional oxygen vacancies, an expansion in crystal volume for enhanced oxygen ion transport, and the formation of holes fostering higher concentrations of electronic conducting carriers, thereby improving oxygen permeability. The membrane’s resilience to pure CO2 exposure, maintaining structure for over 1600 hours, underscores its durability. First-principles calculations reveal Cu/Zn substitution effects on oxygen vacancy formation and transport, accelerating short-range oxygen ion migration. This facilitates faster oxygen permeability, crucial for membrane design. Experimental and computational synergy provides insights into ionic and electronic conductivity, establishing equilibrium for permeability and CO2 tolerance. The newly developed membranes exhibit high potential for applications in separating oxygen from highly concentrated CO2 atmospheres and for plasma-based CO2 conversion and unitization. (Guoxing Chen, Wenmei Liu, Marc Widenmeyer, Xiao Yu, Zhijun Zhao, Songhak Yoon, Ruijuan Yan, Wenjie Xie, Armin Feldhoff，Gert Homm, Emanuel Ionescu, Maria Fyta, Anke Weidenkaff, Front. Chem. Sci. Eng. 2024, 18(6): 62) Download cover

May. 2024, Volume 18 Issue 5

High-purity H2O2 is widely used as an environmentally friendly wet electronic chemical for the production of printed circuit boards, semiconductors and integrated circuits. In this work, the authors prepared primary, secondary and tertiary amino-functionalized zirconia by the postgrafting method, and systematically studied the simultaneous adsorption process of metallic ions (M+, exist typically Al3+, Fe3+, Mg2+, Ca2+, K+, Na+), phosphate and total oxidizable carbon (TOC) from a real H2O2 solution and the adsorption mechanism of M+. The importance of the work is from: 1) Figuring out the relationship between the type of amino groups and adsorption performance of impurities from the 30% H2O2 solution. 2) Finding the promoting effect of coexisted phosphate on adsorption of M+. 3) Revealing the adsorption mechanism of M+ by DFT calculations, combining the experiments of adsorption isotherms and kinetics. 4) Achieving the highly effective adsorption removal of multiple impurities, low leaching of Zr4+ and decomposition of H2O2. (Yu Meng, Yitong Wang, Guozhu Li, Guozhu Liu, Li Wang, Front. Chem. Sci. Eng. 2024, 18(5): 56) Download cover

Apr. 2024, Volume 18 Issue 4

As a new and rare strategic resource, helium plays an irreplaceable role in high-tech fields such as national defense, aerospace, medical treatment and semiconductor. Commercial helium mainly comes from the helium natural gas reservoir, and the distribution of helium resources is unbalanced. The helium resources in our country only account for 2% of the world's helium reserves. Helium is heavily dependent on imports in our country, and the degree of dependence is as high as 95%. Therefore, in view of the lack of helium in our country's natural gas, it is necessary to develop efficient and energy-saving natural gas helium extraction technology. In this paper, an ultra-thin 6FDA-APAF0.5-BIA0.5 copolyimide membrane was prepared by non-solvent induced phase separation method and applied to the separation of He/CH4 and He/N2. (Ying Li, Lu Wang, Junyan Xie, Yong Dai, Xuehong Gu, Xuerui Wan, Front. Chem. Sci. Eng. 2024, 18(4): 44) Download cover

Mar. 2024, Volume 18 Issue 3

This study presents a sea urchin-like Cu2O/Cu catalyst for electrochemical CO2 reduction to C2, which is derived from rhombic dodecahedra Cu2O through one-step oxidation/etching reaction and in situ electrochemical reduction. The sea urchin-like structure provides more active sites and enhances the adsorption of the key intermediate *CO. Meanwhile the formed Cu+/Cu0 interfaces facilitate the C-C coupling reactions between C1 intermediates. As a result, the excellent C2H4 production is achieved through the combined effects of the sea urchin-like structure and the stable Cu+ /Cu0 mixed states. (Mengqing Shan, Dongsheng Lu, Jiatong Dong, Shen Yan, Jinyu Han, Hua Wang, Front. Chem. Sci. Eng. 2024, 18(3): 30) Download cover

Feb. 2024, Volume 18 Issue 2

Effective dispersion of fillers in the matrix is considered an efficient method to enhance the gas separation performance of hybrid membranes. In this study, metal-organic framework (MOF) nanoparticles dispersed in organosilica sol were successfully obtained by introducing urea into the precursor solution during the synthesis process. It was observed that the organosilica hybrid membrane, incorporated with urea-modulated MOF nanoparticles, exhibited a 3.3-fold increase in CO2/CH4 selectivities compared to the hybrid membrane incorporating non-modulated MOFs. These findings demonstrate the significant capability of urea-modulated MOFs to amplify the gas separation performance of hybrid membranes. This simple and feasible strategy can be widely used to produce various MOF-based membranes customized for diverse separation systems. (Yayun Zhao, Dechuan Zhao, Chunlong Kong, Yichao Lin, Xuezhen Wang, Liang Chen, Front. Chem. Sci. Eng. 2024, 18(2): 18) Download cover

Jan. 2024, Volume 18 Issue 1

Overall hydrazine splitting (OHzS) is a promising alternative for overall water splitting (OWS) towards hydrogen production due to the anodic hydrazine oxidation reaction (HzOR) involving less electrons and faster kinetics than oxygen evolution reaction (OER). However, it still remains a challenge to synthesis bifunctional electrocatalyst for hydrogen evolution reaction (HER) and HzOR with low overpotentials. Herein, we report two-dimensional multifunctional layered double hydroxide derived from metal-organic framework sheet precursor supported by nanoporous gold with high porosity and demonstrate its dual appealing activities for both HER and HzOR. Notably, the OHzS cell only needs a cell voltage of 0.984 V to deliver 10 mA·cm－2, which is far more superior than that of the OWS system (1.849 V). Besides, the electrolysis cell could stably operate for more than 130 h. (Xicheng Gao, Jianqiang Bi, Linjie Meng, Lulin Xie, Chen Liu, Front. Chem. Sci. Eng. 2024, 18(1): 6) Download cover

Dec. 2023, Volume 17 Issue 12

Oxygen vacancies engineering is considered to be an effective way to enhance the electrochemical performances of metal oxides for supercapacitors. Herein, NiFe2O4‒δ with abundant oxygen vacancies was obtained through further heat treatment in activated carbon bed on the basis of hydrothermal-synthesized NiFe2O4. It was found that the treated NiFe2O4‒δ owned better conductivity as well as 3.7 times of capacitance than NiFe2O4. The overall results proved that oxygen vacancies could efficiently boost the electrochemical properties of metal oxides, leading to a potential application for supercapacitor electrode material. (Xicheng Gao, Jianqiang Bi, Linjie Meng, Lulin Xie, Chen Liu, pp. 2088–2100) Download cover Download table of contents

Nov. 2023, Volume 17 Issue 11

COVER
Carbon materials are prefect catalysts and supports for dehydrogenation reactions due to their stable structure, rich pore texture and diverse surface functional groups. The review summarized various carbon-based catalysts, including ordered mesoporous carbon, carbon nanodiamond, carbon nanotubes, graphene and activated carbon. The discussion of unique structure, dehydrogenation mechanism, active site and ingenious preparation method illustrates the current development of carbon-based catalysts. The analyzation of their catalytic performance enhancement method like reasonable synthesis method and heteroatom doping, provides guidance for their design and improvement in the futural research. (Sijia Xing, Sixiang Zhai, Lei Chen, Huabin Yang, Zhong-Yong Yuan, pp. 1623–1648) Download cover

Oct. 2023, Volume 17 Issue 10

COVER
Solving the integrated problem of long-term planning and short-term scheduling in a large-scale refinery-petrochemical complex has been a big challenge over the past years. The mixed-integer nonlinear programming model is usually intractable due to the vast binary variables which increase the computational expenses. Therefore, a data-driven approach is proposed based on the idea of predicting the final objective with given integer variables. A convolutional neural network (CNN) is implemented for such purpose and combined with classical optimization as a heuristic algorithm. In this approach, the CNN is first used to decide whether the given integer variables are the potential to provide a satisfactory solution. If the prediction is positive, then the resulting nonlinear model is solved to optimality. The final solution is updated when a better solution is obtained. Via such a framework, the complex integrated planning and scheduling problem can be solved much more efficiently compared to commercial solvers BARON and SCIP, showing advantages in a realistic application. (Lifeng Zhang, Haoyang Hu, Zhiquan Wang, Zhihong Yuan, Bingzhen Chen, pp. 1516–1532) Download cover Download table of contents

Sep. 2023, Volume 17 Issue 9

COVER
Windmills and solar photovoltaic panels staggered on top of the mountains and greenery, with vanadium redox flow batteries to provide energy for the human world and life storage. At the bottom, the cell sketch shows the conversions of various valence electrolytes and energy. The enlarged view demonstrates the organic additives with different functional groups involved in the vanadium ion structure and electrode interface reaction process. The vast blue sky and white clouds express the beauty role and aspiration of safe and green vanadium electrolyte energy storage for a world full of bright and low-carbon. (Ling Ge, Tao Liu, Yimin Zhang, Hong Liu, pp. 1211–1230) Download cover

Aug. 2023, Volume 17 Issue 8

Jul. 2023, Volume 17 Issue 7

Download cover

Jun. 2023, Volume 17 Issue 6

Titanium silicalite-1 (TS-1) zeolites are the efficient and clean catalysts for producing the important epoxidized products in the epoxidation of alkenes. Herein, the size-controlled synthesis of the TS-1 (TS-1#ACh) catalysts was carried out by introducing acetylcholine (ACh) as a crystal growth regulator. Large-sized TS-1#0.1ACh catalysts show excellent tetrahedrally coordinated framework Titanium, which provides good catalytic performance and stability in the epoxidation of allyl chloride. Furthermore, TS-1#0.1ACh exhibit also highly versatile and effective for epoxidation of the unsaturated substrates with different carbon chains. (Xiu Gao, Beining Luo, Yanping Hong, Peihang He, Zedong Zhang, Guoqiang Wu, pp. 772–783)

May. 2023, Volume 17 Issue 5

An iron-coordinated covalent triazine polymer-derived Fe–Nx nanoparticle-embedded nitrogen-doped carbon nanofloret composite is successfully designed by Liu and co-workers. Thanks to its abundant Fe–Nx nanoparticles active centers and large specific surface area, the optimal Fe/N@-CNF-800 can readily work as an efficient pH-universal electrochemical oxygen reduction catalyst for a high-performance zinc-air battery. (Yong Zheng, Mingjin Li, Yongye Wang, Niu Huang, Wei Liu, Shan Chen, Xuepeng Ni, Kunming Li, Siwei Xiong, Yi Shen, Siliang Liu, Baolong Zhou, Niaz Ali Khan, Liqun Ye, Chao Zhang, Tianxi Liu, pp. 525–535)

Apr. 2023, Volume 17 Issue 4

Radioactive iodine exhibits medical values in radiology, but its excessive emissions can cause environmental pollution. Thus, the capture of radioiodine poses significant engineering for the environment and medical radiology. On the cover image, a Th-based MOF (Th-BPYDC) with octahedral structure was synthesized by hydrothermal methods, consisting of 12-linked polyhedral [Th6(μ3-O)4(μ3-OH)4((H2O)6]12+ clusters, abundant bipyridine units and large cavities allowing diffusion and transport of the guest iodine molecule. Th-BPYDC exhibited an effective uptake capacity for I2 vapor and dissolved I2 in cyclohexane, surpassing its corresponding analogue Th−UiO−67. The bipyridine units boosted the adsorption performance, resulting Th-BPYDC with good reusability and high stability. Therefore, the construction of nitrogen-rich bipyridine units on Th-MOF can immensely improve the adsorption capacity for radioiodine, and the feasibility of this strategy provide a new idea for radioiodine capture in spent nuclear fuels treatment. (Xinyi Yang, Xiaolu Liu, Yanfang Liu, Xiao-Feng Wang, Zhongshan Chen, Xiangke Wang, pp. 395-403)

Mar. 2023, Volume 17 Issue 3

Membrane separation is a promising method for producing clean and renewable bio-ethanol, and there is a high demand for membrane selectively permeating ethanol or water molecules. Two-dimensional graphene is emerging as a promising membrane candidate owing to its atomic-thick structure. Through molecular simulation study, Quan Liu and co-workers reveal a novel two-way selective mechanism in graphene-based membranes that allows for customizable separation of ethanol/water mixtures. Pristine graphene membranes contain hydrophobic carbon rings that selectively attract ethanol molecules, resulting in ethanol-enriched pores and water-repelling pores. On the other hand, hydroxylated graphene, which contains polar functional groups, preferentially filters water molecules through a combination of functional-group attraction and molecular sieving effect. Simulation under operando conditions shows that the pristine graphene with a properly-sized aperture achieves exceptional ethanol-perm-selective separation. These findings provide new insights into reverse-selective behavior and pave the way for designing two-dimensional-material membranes for biofuel production. (Quan Liu, Xian Wang, Yanan Guo, Gongping Liu, Kai-Ge Zhou, pp. 347–357)

Feb. 2023, Volume 17 Issue 2

Cover illustration The picture is set against the bright starry sky, symbolizing the broad application prospect of new energy batteries. The main body is the aqueous zinc-ion battery which is being rapidly charged and discharged, which conveys the advantages of aqueous zinc-ion battery such as low cost and high safety. The upper left part of the cover shows the bright moon in the sky, which reflects the potential application prospects of the aqueous zinc-ion battery. The upper right part of the cover shows the crystal structure of α-MnO2@g-C3N4 nanocomposite, with α-MnO2 and g-C3N4 emitting light like stars in the night sky. This study provides certain guidance and reference value for the application of g-C3N4 material in energy storage and the preparation of carbon-nitrogen based green carrier materials. (Jiwei Xie, Guijing Liu, Kaikai Wang, Xueming Li, Yusen Bai, Shanmin Gao, Leqing Fan, Rundou Zheng, pp. 217–225)

Jan. 2023, Volume 17 Issue 1

Cover illustration The amination of alkyl alcohols is one of the most promising paths to synthesize aliphatic amines. Herein, cerium modified nickel-based catalysts were synthesized for the gas-phase amination of alkyl alcohol. It was found that the activity of amine is significantly enhanced by doping the Ni/γ-Al2O3 catalyst with cerium. The overall synergy of Ni nanoparticles and acid sites on Ni–Ce/γ-Al2O3 catalyst boosts its catalytic performance in the amination of alkyl alcohols. (Pengfei Li, Huijiang Huang, Zheng Wang, Ziying Hong, Yan Xu, Yujun Zhao, pp. 82–92)

Dec. 2022, Volume 16 Issue 12

The direct coal liquefaction follows radical reaction mechanism, and the product distributions are determined by varied reaction behavior of the radicals. Among them, the release of free radical is mainly related to the chemical bond composition of the organic structure in coal, and lignite contains a large amount oxygen, which generates oxygenated aromatic compounds in thermal conversion. However, in direct coal liquefaction, a “hydrogen-rich” environment is a distinctive feature, where the oxygen element in the coal is easily converted to water, resulting in the waste of hydrogen and oxygen elements. The direct coal liquefaction is initiated by the generation of free radicals in pyrolysis, which leads to the hydrogen abstract reaction by radicals. The hydrogen abstraction can be followed by the spontaneous shedding of an H atom from the hydrogen-donor solvent, thus completing the removal of two H atoms from the hydrogen-donor solvent. The spontaneous shedding of H radicals will be used to stabilize radicals as well as radical-induced pyrolysis, thus affecting the distribution of the product. The proposed two-step hydrogen supplying and H radical-induced mechanism complements the radical reaction mechanism of the direct coal liquefaction. (Wang Li, Wen-Ying Li , Xing-Bao Wang, Jie Feng, pp. 1689–1699)

Dec. 2022, Volume 16 Issue 11

The separation of rare earth elements is particularly difficult due to their similar physicochemical properties. Based on the differences of ionic magnetic moment via quasi-liquid strategy, two typical paramagnetic and diamagnetic rare-earth ions, Er3+ and Y3+, are separated in the external magnetic field. The paramagnetic Er3+ in ionic liquid is rapidly attracted to the permanent magnet and gathered around the magnet finally, while the diamagnetic Y3+ has no response with the magnet. The ionic liquid herein provides a quasi-liquid surrounding of the rare-earth ions, which efficiently promotes the magnetism differences of Er3+ and Y3+. The separation factors of Er/Y can be achieved at 9.0, six times of that in the traditional 2-ethylhexylphosphonic acid mono-(2-ethylhexyl) ester(P507)-HCl-kerosene system. Meanwhile, the separation factors of Ho/Y, another neighboring rare earth elements as a challenging separation couple, is up to 28.82 with the similar process. Magnetic separation via quasi-liquid system strategy provides a possibility of the novel, green, and efficient method for rare earth separation. (Na Wang, Fujian Li, Bangyu Fan, Suojiang Zhang, Lu Bai, Xiangping Zhang, pp. 1584–1594)

Oct. 2022, Volume 16 Issue 10

Epoxy resin products exhibit some intrinsic limitations of poor fire resistance and low tribology features under dry sliding, making them not suitable for many professional applications. Thus, the comprehensive properties of EP composites must be boosted to meet the needs when served as engineering parts and broaden their application field in high-demanding circumstances. Nie and his co-workers utilized the metal–organic framework as the hard template and nickel source to synthesize whisker-shaped nickel phyllosilicates. With the introduction of low-content of whisker-shaped nickel phyllosilicate, the wear resistance and self-extinguishing performance of composites are excellent compared with pure epoxy resin, proving that the whisker-shaped nickel phyllosilicates can serve as effective reinforcements to enhance fire resistance and tribological properties. This study suggests that whisker-shaped nickel phyllosilicate is a promising reinforcement in preparing high-performance epoxy-based materials. (Yuxuan Xu, Guanglong Dai, Shibin Nie, Jinian Yang, Song Liu, Hong Zhang, Xiang Dong, pp. 1493–1504)

Sep. 2022, Volume 16 Issue 9

In this work, it was reported new hydrogel soft material, which can realize the recovery of raw materials and the regeneration of new hydrogels. Conjugated acceptors containing bismethylthiol esters were employed as hydrogel crosslinkers to be substituted by amine derivatives. Four-arm PEG amine was utilized to react with the representative CAs to prepare highly cross-linked polymers. These materials were characterized by their structure, morphology and mechanical properties. These materials can be triggered by ethylenediamine to degrade completely within hours. The original reactant four-arm PEG amine was recovered, and regenerated the hydrogel using the recovered raw material. This innovative recycled polymer demonstrates the potential application of the new material in terms of manufacturing cost savings and material sustainability. (Xing Feng, Meiqing Du, Hongbei Wei, Xiaoxiao Ruan, Tao Fu, Jie Zhang, Xiaolong Sun, pp. 1399–1406)

Aug. 2022, Volume 16 Issue 8

The micro-nano composite structure can endow separation membranes with special surface properties. Herein, a novel and simple atomization-assisted nonsolvent induced phase separation method has been developed. By using this method, a bicontinuous porous microfiltration membrane with robust micro-nano composite structure was obtained via commercially available polymers of polyacrylonitrile and polyvinylpyrrolidone. The membrane exhibits superhydrophilicity in air and superoleophobicity underwater. The membrane can separate both surfactant-free and surfactant-stabilized oil-in-water emulsions with high separation efficiency and permeation flux. With excellent antifouling property and robust microstructure, the membrane can be easily recycled for long-term separation. The simple, efficient, cost-effective preparation method and excellent membrane properties indicate the great potential of the developed membranes in practical applications. (Jing Wang, Guoyuan Pan, Yu Li, Yang Zhang, Hongwei Shi, Xuanbo Liu, Hao Yu, Muhua Zhao, Yiqun Liu, Changjiang Wu, pp. 1268–1280)

Jul. 2022, Volume 16 Issue 7

Cover illustration Targeting at the conflict between growth and production, a dual temperature control system is developed for yeast engineering based on the expression and activity control of the transcriptional activator Gal4, which acts as a switch to regulate the direction of carbon flux. Temperature change serves as an input signal to trigger the expression of the Gal4 mutant under a heat-shock promoter, and meanwhile to activate it due to its cold-sensitive feature. By changing the culture temperature from 30 °C to 37 °C, both the expression level and activity of the Gal4 mutant are increased, which re-directs the carbon flux from cell growth to product synthesis. In this way, the cellular burden caused by isoprene biosynthesis via a mitochondria-compartmented pathway could be relieved, leading to reconstruction of balance between cell growth and isoprene production. (Jiaxi Lin, Zhen Yao, Xiaomei Lyu, Lidan Ye, Hongwei Yu, pp. 1079–1089)

Jun. 2022, Volume 16 Issue 6

Inspired by the integration process, aluminum hydrogel (alum)-stabilized oil-in-water emulsions (ASEs) was assembled in a modular way. The oil phase was screened thoroughly for the enhanced anti-oxidative capability and long-term-storage stability. Subsequently, alum was adsorbed and packed on the squalene/water interphase, forming the particulate emulsion droplet. With the hydrophobic and electrostatic interactions, the droplet increased the antigen loading efficiency and induced potent antigen-specific antibody secretion and T-cell-mediated immune responses. Furthermore, the acceptable biosafety profile was also elicited. The featured paper also studied the the underlying mechanisms of droplet stability and the boosted immunogenicity, which may offer an alternative strategy for safe, stable, and effective emulsion adjuvants. (see Lili Yuan, Xiao-Dong Gao, Yufei Xia, pp. 973–984)

May. 2022, Volume 16 Issue 5

(Rongzhen Chen, Xinfei Dong, Qingchun Ge, pp. 755–763)
As draw solute is the core element of forward osmosis (FO), here Li-Bet-Tf2N synthesized from a customized ionic liquid betainium bis(triflfluoromethylsulfonyl)imide ([Hbet][Tf2N]) and Li2CO3 recovered from lithium-ion battery (LIB) wastes is proposed as a draw solute to treat Li+-containing wastewater from LIB manufacturing through FO filtration. Li-Bet-Tf2N generates a sufficiently high osmotic pressure to drive the FO separation efficiently. Li-Bet-Tf2N produces a water flux of 21.3 L·m−2·h−1 at 1.0 mol∙L‒1 against deionized water, surpassing conventional NaCl and MgCl2 draw solutes with higher water recovery efficiency. Moreover, Li-Bet-Tf2N induces higher water permeation flux with a 10.0% water flux decline than NaCl and MgCl2 for which the water flux decline 16.7% and 16.4%, respectively, in treating 2000 mg∙L‒1 Li+-containing wastewater for 12 h. Remarkably, unlike other draw solutes which require intensive energy input in recycling, Li-Bet-Tf2N is easily separated from water via solvent extraction. Li-Bet-Tf2N thus demonstrates a novel class of draw solute with great potentials to treat wastewater economically.

Apr. 2022, Volume 16 Issue 4

(Jinian Yang, Xuesong Feng, Shibin Nie, Yuxuan Xu, Zhenyu Li, pp. 484–497) Due to the intrinsic drawbacks of relatively high brittleness and poor wear resistance, epoxy products cannot undergo the rubbing actions under dry sliding and hard to be sate when served as engineering parts. Yang et al. propose a promising solution to solve the above problem by introducing low-content flower-like nickel phyllosilicates to yield the cost-effective epoxy nanocomposites with highly restricted abrasions. Flower-like particles are well-constructed firstly and then served as effective reinforcements to enhance the mechanical, thermal and tribological properties, and finally the possible wear mechanism involved in present friction process is discussed thoroughly. This study attempts to provide a facile route for the development of high-performance epoxy-based friction materials.

Mar. 2022, Volume 16 Issue 3

(Hongtao Xie, Qin Geng, Xiaoyue Liu, Jian Mao, pp. 376–383)
Rational design of highly efficient electrocatalysts for oxygen evolution reaction (OER) is critical for sustainable energy conversion. Herein, a novel bijunction CoS/CeO₂ OER electrocatalyst grown on carbon cloth is prepared through electrodeposition. Such a CoS/CeO₂/CC electrocatalyst exhibits outstanding OER catalytic activity with a low overpotential of 311 mV at 10 mA•cm⁻² and a low Tafel slope of 76.2 mV•dec⁻¹. This is because the interface engineering of CoS and CeO₂ facilitates charge transfer and active sites and the rich oxygen vacancies of CeO₂ film promote the absorption of oxygen species in the medium. Download cover

Feb. 2022, Volume 16 Issue 2

(Teng Zhou, Kai Sundmacher, pp. 137−140)
A process system can be generally decomposed into hierarchical levels or scales at which different physical and/or chemical phenomena take place.

Jan. 2022, Volume 16 Issue 1

(Yongqing Zhou, Xin Wang, Wei Zhang, Bo Tang, Ping Li, pp. 4–33)
Fluorescent technology associated with small molecular probes have been widely used for studying of molecular events in biological systems due to its excellent performances, including noninvasive, high sensitivity and selectivity, and high spatial temporal resolution. Particularly, small molecule fluorescent probes have been successively developed to simultaneously monitor two biomolecules to uncover their interrelationships and synergistic regulations in related diseases. In this review, we focus on summarizing the design strategies, classifications, and bioimaging applications of dual-response small molecule fluorescent probes over the past decade. Furthermore, challenges and future research directions in this field are proposed in brief.

Dec. 2021, Volume 15 Issue 6

(Hao-Yu Wang, Chen-Chen Weng, Jin-Tao Ren, Zhong-Yong Yuan, pp. 1408–1426)
The development of earth-abundant electrocatalysts for hydrogen production from low-grade and saline water with renewable electricity is highly desired but very challenging due to the interference of side reactions and various impurities. Yuan et al. give a conceptual understanding of direct seawater splitting with the difference to the electrolysis in pure water. Effective strategies for the rational construction of electrocatalysts with improved selectivity and stability on both anode and cathode based on possible electrochemistry involved in this process are discussed, including thermodynamically restricting chloride chemistry, designing selective active species and constructing protecting layers. Rational design of highly efficient and stable electrolysers is also required for the implement of direct seawater electrolysis. For the guidelines of future research, recent achievements are discussed and issues to be solved are provided. Download cover

Oct. 2021, Volume 15 Issue 5

(Hui Shang, Chong Guo, Pengfei Ye, Wenhui Zhang, pp. 1088‒1098)
The development of hydrodesulfurization (HDS) technology is urgent for the production of clean gasoline due to the strict environmental regulations. Major challenge is to increase the HDS performance while reduce the hydrogenation of olefins, which contributes a lot gasoline octane number. The special interaction between microwave and the material’s molecules highlights the obvious advantages by using microwave in the area of HDS of petroleum oils. The HDS catalyst prepared by microwave heating presents enhanced properties as enlarging the surface area, reducing the acidity of the support, improving the stacking numbers of the active components, all of which contributes to higher HDS performance. The study of the synergistic effect between microwave and catalyst is the key to microwave high efficiency HDS technology, which is of great significance to the production of ultra-low sulfur clean gasoline. Download cover

Aug. 2021, Volume 15 Issue 4

(Wei Wang, Yanying Wei, Jiang Fan, Jiahao Cai, Zong Lu, Li Ding, Haihui Wang, pp. 793‒819)
Membrane-based separation technologies have received increasing attention attributing to lots of advantages such as the low energy consumption, easy operation, and environmental friendliness. Two-dimensional (2D) materials have emerged as a class of promising materials to prepare high-performance 2D membranes for various separation applications. The precise control of the interlayer nano-channel/sub-nanochannel between nanosheets or the pore size of nanosheets within 2D membranes enables 2D membranes to achieve promising molecular sieving performance. To date, many 2D membranes with high permeability and high selectivity have been reported, exhibiting high separation performance. This review presents the development, progress, and recent break-through of different types of 2D membranes, including membranes based on porous and non-porous 2D nanosheets for various separations. Separation mechanism of 2D membranes and their fabrication methods are also reviewed. Last but not the least, challenges and future directions of 2D membranes for wide utilization are discussed in brief. Download cover Download table of contents

Jun. 2021, Volume 15 Issue 3

(Yingying Jian, Danyao Qu, Lihao Guo, Yujin Zhu, Chen Su, Huanran Feng, Guangjian Zhang, Jia Zhang, Weiwei Wu, Ming-Shui Yao, pp. 505‒517)
Ti₃C₂T_x MXene, a two-dimensional (2D) materials with ultra-thin structure, has been fabricated as gas sensors working at room temperature with various thickness. In this work, two critical features towards reducing gases (NH₃ and CO) and oxidizing gas (NO₂) are characterized in a dynamic model. On one hand, the thickness of the Ti₃C₂T_x MXene material affects the sensing performance that the response to gases is declined with the increasing thickness of the Ti₃C₂T_x MXene. On the other hand, the Ti₃C₂T_x MXene based gas sensor is not appropriate for strong and moderate oxidizing gas (NO₂) compared with the reducing gases (NH₃ and CO). These two rules are demonstrated, and could be considered with priority both in the future researches and practical applications. Download cover Download table of contents

Apr. 2021, Volume 15 Issue 2

(Fernando F. Rivera, Berenice Miranda-Alcántara, Germán Orozco, Carlos Ponce de León, Luis F. Arenas, pp. 399‒409)
Redox flow batteries are being developed to contribute to the large-scale energy storage required for the full implementation of renewable energy sources. A grid incorporating energy storage is capable of managing the load-levelling needs set by wind and solar power. Among the proposed chemistries, cerium-based systems are interesting due to their relatively high cell voltage. Our work presents validated CFD simulations of two relevant materials for the positive electrode of this device: a 2D planar electrode (and a polymer mesh spacer) and a 3D expanded metal mesh. Turbulent Reynolds-averaged Navier-Stokes and free flow plus porous media models were applied to compute local fluid velocities within a rectangular channel flow cell for laboratory studies. Calculated pressure drop was compared to experimental data. Pressure drop was described by the RANS approach, whereas the validity of Brinkman equations was dependent on the permeability of the porous media. Download cover Download table of contents

Feb. 2021, Volume 15 Issue 1

(Faraz Montazersadgh, Hao Zhang, Anas Alkayal, Benjamin Buckley, Ben W. Kolosz, Bing Xu, Jin Xuan, pp. 937‒947)
The cover image shows the vision of our e-bio-fuel project, joint funded by the UK’s Department of Transport and SuperGen Bioenergy Hub in 2019. It aims to develop a new electrochemical platform to produce low-carbon fuels through integrated co-valorisation of biomass feedstocks with captured CO₂. In this approach, CO₂ is reduced at the cathode to produce drop-in fuels while value-added chemicals and fuels are produced at the anode from selective oxidation of bio-feedstocks. Our vision is to intensively increase the sustainability of the road transport sector, while enhancing renewable energy security.
In this work, a numerical model of a continuous-flow e-bio-fuel electrochemical reactor considering various anodic and cathodic reactions was built to determine the most techno-economically feasible configurations from the aspects of energy efficiency, environment impact and economical values. The reactor design was then optimized via parametric analysis. Through the study, the feasibility of our e-bio-fuel process has been proven.
Download cover Download table of contents

Dec. 2020, Volume 14 Issue 6

(Mehraneh Ghavami, Mostafa Aghbolaghy, Jafar Soltan, Ning Chen, pp. 937‒947)
Volatile organic compounds (VOCs) are among the major sources of air pollution. VOCs in indoor air are released from human activities and a wide variety of materials such as cleaning agents, floorings, paints, surface coatings, and furniture. Using ozone in catalytic oxidation of VOCs is a potential air treatment method with benefits such as decreasing reaction temperature and possibility of using transition metal oxides instead of precious metals.
We studied catalytic ozonation of acetone over a series of alumina supported single and mixed Mn-Co oxides catalysts at room temperature. Alumina acts as a reservoir for acetone and it interacts with acetone to create surface carboxylate intermediates. Surface carboxylates migrate to the metal sites and react with highly active atomic oxygen species produced from ozone decomposition. The intermediates are oxidized on the metal sites to produce CO₂ and water.
The addition of lower loading of Co as secondary metal to Mn catalysts improved activity of the catalysts significantly. By augmenting the catalyst with the second metal with lower loading, the local structure and oxidation states are affected. Catalysts having lower oxidation states are more active in transferring electrons to ozone, leading to higher ozone decomposition, and thus enhanced acetone oxidation.

Oct. 2020, Volume 14 Issue 5

(Zhaoyou Zhu, Guoxuan Li, Yao Dai, Peizhe Cui, Dongmei Xu, Yinglong Wang, pp. 824‒833)
The traditional approach of solvent selection in the extractive distillation process strictly focuses on the change in relative volatility of the light-heavy component caused by the solvent. However, the total annual cost of the process may not be minimal when the solvent causes the greatest change in relative volatility. This work presents a heuristic method to select the optimal solvent to minimize the total annual cost. The functional relationship between the relative volatility and the total annual cost is established, where the main factors, such as the relative volatility of the light-heavy component and relative volatility of the heavy-component solvent, are taken into account. Binary azeotropic mixtures of methanol-toluene and methanol-acetone are separated to verify the feasibility of the model. The result shows that the total annual cost of the process by using the solvent with the minimal two-column extractive distillation index is the lowest. This study provides a rapid and effective design strategy for the preliminary selection of solvents in extractive distillation.

Aug. 2020, Volume 14 Issue 4

(Anna Khlyustova, Nikolay Sirotkin, pp. 513‒521)
Benzoic acid is used in textiles, plastics, chemicals, powders, catalyst, and for wood bleaching. The solutions of benzoic acid are corrosive, toxic and poisonous and they should be removed from water. Plasma in contact with liquids is one of the methods of advanced oxidation processes. Plasma treatment can lead to destruction as well as synthesis processes. It was proved in the experiments with benzoic acid. At the small time of treatment the mono- and dihydroxyderivatives of benzoic acid are formed. At the long time of treatment, benzoic acid is destroyed via formation of quinones.

Jun. 2020, Volume 14 Issue 3

(Cyrine Ayed, Wei Huang, Kai A. I. Zhang, pp. 397‒404)
A hybrid material consisting of a covalent triazine framework and mesoporous silica was designed and used as visible light-active, highly efficient, stable and reusable photocatalyst in water. Due to the high surface area and the added hydrophilic properties by silica, the hybrid material demonstrated excellent adsorption of organic molecules in water, leading not only to high photocatalytic performance of the hybrid material for the degradation of organic dyes in water, but also for efficient photocatalysis in solvent-free and solid state in air.

Apr. 2020, Volume 14 Issue 2

(Yujie Ban, Meng Zhao, Weishen Yang, pp. 188‒215)
CO₂ capture is a hot topic in research and industry. It typically refers to the splitting of CO₂/N₂, H₂/CO₂ and CO₂/CH4, and is one of the most desirable separation technologies in environment and energy sectors. Membrane-based separations are energy-efficient separation methods cutting the energy consumption of traditional distillation by nearly 90%, which offers hope for CO₂ capture. Metal-organic frameworks (MOFs) are a versatile platform with compositional and structural tunability, lighting the concept from precise material design to membranes for high-efficiency CO₂ capture. This review summarized compositional/structural design and regulation strategies of MOFs targeted at secondary building units (metal nodes and linkers), pore structure, topology and mixed-phase hybrid structures for achieving CO₂-philic MOF materials. And diversified methods were illustrated for construction of improved MOF membranes that can overcome the bottleneck of permeability-selectivity limitations.

Feb. 2020, Volume 14 Issue 1

Dec. 2019, Volume 13 Issue 4

(Evelyn Chalmers, Yi Li, Xuqing Liu, pp. 684-694)

Sep. 2019, Volume 13 Issue 3

(Bin Xu, Toshiro Kaneko, Toshiaki Kato, pp. 517-524)
This cover figure shows an innovative growth method of SWNTs with narrow-chirality distribution, named pulse plasma chemical vapor deposition (CVD). The growth yield of the SWNTs could be improved by repetitive short duration pulse plasma CVD, while maintaining the initial narrow chirality distribution. This study on the precise time-scale incubation dynamics controlling the growth of SWNTs during pulse plasma CVD offers novel insights for the development of chirality-controlled SWNTs.

Jun. 2019, Volume 13 Issue 2

(Rusen Zhou, Renwu Zhou, Xianhui Zhang, Kateryna Bazaka, Kostya (Ken) Ostrikov, pp. 340-349)
Electrifying chemical industry for cleaner future
Plasma technology is one of the most promising innovations to electrify the chemical engineering field with applications varying from pollution abatement to energy conversion. New engineering solutions are poised to arise based on synergistic plasma effects. In this issue, Zhou et al. demonstrate that synergizing a dielectric barrier discharge plasma water bed with activated carbon adsorption allows large amount of wastewater to be treated to meet drainage standards while reducing treatment time and energy consumption. This effort reveals how collaboration across chemical engineering and plasma applications can contribute to the solution of persistent environmental and energy problems and to create a cleaner, greener and more sustainable planet.

Feb. 2019, Volume 13 Issue 1

(Dongjie Yang, Shengyu Wang, Ruisheng Zhong, Weifeng Liu, Xueqing Qiu, pp. 630-642)
Lignin is one of the most abundant biomass resources and it makes up 20 wt-%‒30 wt-% of lignocellulose. It endows plants with their natural toughness and UV resistance. The pulp and paper pulping industry generates more than 50 million tons of technical lignin annually. However, most of the technical lignin is not properly utilized. Lignin is renewable, biodegradable, non-toxic, inexpensive and widely available, so the efficient and comprehensive utilization of lignin is of great significance to sustainable chemical industry. For the first time, a simple and effective sol-gel method has been developed for the preparation of lignin/TiO₂ nanocomposites in an aqueous medium. The as-prepared lignin/TiO₂ nanocomposites contain well-dispersed small particles with excellent UV shielding ability and good compatibility with waterborne polyurethane (WPU). When the lignin/TiO₂ nanocomposites were blended with WPU, the tensile ductility, the UV absorbance and anti-UV aging performance of the WPU films increased significantly. This work highlights new possibilities for the utilization of alkali lignin.

Jan. 2019, Volume 12 Issue 4

(Timothy G. Walmsley, Nathan S. Lal, Petar S. Varbanov, Jiří J. Klemeš, pp. 630-642)
Ever increasing energy costs and environmental concern drives a cycle of continuous process energy improvement in the chemical and process industries. To remain competitive in the short-term and sustainable in the long-term, industrial companies and sites need to identify projects to retrofit and revamp their technology to keep pace with more energy-efficient new plants. Such options include disruptive projects (e.g., new reactor installation) or incremental improvement (e.g., new heat exchangers). Due to the capital intensity of disruptive change, most companies favour incremental, low-risk improvements to stay viable.
Our research focuses on developing techniques to analyse existing processing plants, understand its heat transfer operations and flows, and identify options to improve its energy efficiency. We call our new method the Automated Retrofit Targeting (ART) algorithm. A unique feature of the algorithm is the comprehensive search function that systematically looks at all possible pathways to save energy starting from the current network of operations. We presented a case study on a section of a refinery (27 streams and 46 existing heat exchangers) and found over 68903 feasible, unique retrofit opportunities. The most promising of these retrofit projects required 3 new heat exchanger units and reduced steam use by 4.24 MW.

Sep. 2018, Volume 12 Issue 3

(Walter Kaminsky, pp. 555-563)
The cover page shows a computer model of a unit structure of methylaluminoxane (MAO). The unit structure contains 4 aluminum atoms, separated by 3 oxygen atoms and 6 methyl groups and associate to larger cages. MAO is the most important cocatalyst to activate transition metal complexes such as metallocens for the polymerization of olefins. The metallocene/MAO catalyst is soluble in hydrocarbons and can be varied by changing the molecular structure of the metal complex (single site catalyst). The activity is about 10 times higher than that of classical Ziegler-Natta catalysts. Today more than 10 million tons of polyethylene and ethylene/propylene copolymers are produced per year by MAO containing catalysts.

May. 2018, Volume 12 Issue 2

(Adam C. Sedgwick, Alex Hayden, Barry Hill, Steven D. Bull, Robert B. P. Elmes, Tony D. James, pp. 311-314)
The cover shows carrot spacecraft piloted by rabbits.
Link between the picture and the science contained in the paper: Umbelliferone a coumarin fluorophore was used to prepare the sensor employed in this project and is found in carrots. When our sensor reacts with the nitoreductase (NTR) enzyme it releases the fluorescent blue umbelliferone molecule. Nitroreductase (NTR), is one of a series of biomarkers that have been shown to be significantly upregulated in cells under hypoxic stress. Hypoxia is a condition where cells are deprived of adequate oxygen.
Therefore the picture is set in space with the moon representing a cell under hypoxic stress. Therefore, the carrot spacecraft burrowing into the moon change from orange to blue representing the release of the fluorescent blue umbelliferone under hypoxic conditions. The Earth has normal oxygen levels and so no carrot spacecraft have targeted the earth. Importantly, even if they had targeted and burrowed into the Earth they would have remained orange due to the normal oxygen levels.

Feb. 2018, Volume 12 Issue 1

(Dongxu Han, Zhiguo Zhang, Zongbi Bao, Huabin Xing, Qilong Ren, pp. 113‒123)
Bimetallic nanocatalysts not only combine the properties of individual constituents but also may have enhanced catalytic activity, selectivity, and stability. This may be attributed to the modulation of the charge transfer between different metals and surface element distribution. Thus, the development of bimetallic nanoparticles, in particular, palladium with non-noble metals, has long proven value in the past few years. Among Pd-non-noble metal NPs reported, Pd-Ni NPs have demonstrated to be efficient and economic catalysts for diverse transformations. In this paper, we successfully prepared TiO₂-supported Pd-Ni nanoparticles with the mean diameter of approximately two nanometers through a one-step impregnation reduction route. The as-prepared Pd-Ni/TiO₂ exhibited enhanced catalytic activity compared to an equal amount of Pd/TiO₂ as well as excellent stability, recyclability and applicability in the Suzuki-Miyaura reactions. The catalytic results show that the substrate iodobenzenes and phenylboronic acids bearing with either electron-donating or electron-withdrawing groups gave the corresponding product in excellent yields. Besides, there was no considerable loss in catalytic activities of the Pd-Ni/TiO₂ catalyst after four recycles. Moreover, among these Pd-Ni/TiO₂ catalysts with different compositions of Ni and Pd, the one with the Ni:Pd ratio of 2.95 showed the best activity.

Nov. 2017, Volume 11 Issue 4

(Xiaobin Jiang, Linghan Tuo, Dapeng Lu, Baohong Hou, Wei Chen, Gaohong He, pp. 647-662)
Development of membrane science and technology gives more inspiration to chemical engineering researchers in variety of fields. Membrane distillation crystallization (MDC) is a promising hybrid separation process that has been applied to seawater desalination, brine treatment and wastewater recovery. In recent years, great progress has been made in MDC including the promotion of nucleation control of crystallization and crystal size distribution modification. The progress is not only shed light on chemical industry, but also biological and pharmaceutical engineering, etc. Membrane assisted approach provides an alternative approach for the controllable and stable the supersaturation degree and nucleation control. In addition, allowing for the potential integrated MDC with other processes, the development of MDC process models and controlling strategies design should be paid intensive attention. By summarizing the most important innovative applications in MDC, which are developed for crystal engineering and pharmaceutical manufacturing, this review is aimed to overview the progress in MDC and outline the future research direction and potential applications.

Aug. 2017, Volume 11 Issue 3

The authors of Special Topic on environment and sustainable development come from China, USA, Canada, Italia, the Netherlands and Belgium, thereby forming a union of chemical engineering from China, Europe, and North America.

May. 2017, Volume 11 Issue 2

(See Yong Zhu, Zhishan Bai, Bingjie Wang, Linlin Zhai, Wenqiang Luo, pp 238-251)
The novelty of this article is focusing on the synthesis method of microfluidic technology. Microfluidic technology occupies high position in product control for the controllable size, structure, component and morphology. The key part of microfluidic equipment is the chip. The continuous phase was pumped into microfluidic chip to sheer dispersed phase at the cross aisle. Dispersed phase necked first under extrusion and shear force, and then it drew and broke into a spherical microsphere finally for its own surface tension. The microsphere flowed through outlet steadily and uniformly into a beaker filled with solidification bath for crosslinking. These microspheres would become impact, stable and plastic after crosslinking. Prepared microspheres were extremely monodispersed, uniform-sized, highly spherical and smooth-faced. The CV value of these prepared microspheres in our work is 1.52%, greatly lower than those CV of microsphere prepared with membrane emulsification or suspension polymerization approaches which were usually about 10%. High monodispersed microspheres could separate out of medium completely or be convenient to handle. The adsorption behavior of these microspheres towards copper (II) and main influencing factors on adsorption performance had been investigated by batch experiments. These microspheres also showed excellent adsorption selectivity and renewability. All these researches provided a brand new direction for preparing highly comprehensive performance sorbent via microfluidic technology.

Mar. 2017, Volume 11 Issue 1

(Ting Yuan, Yakun Guo, Junkai Dong, Tianyi Li, Tong Zhou, Kaiwen Sun, Mei Zhang, Qingyu Wu, Zhen Xie, Yizhi Cai, Limin Cao, Junbiao Dai, pp. 107-116)
One critical step in metabolic engineering is to optimize, both spatially and temporally, the expression of key enzymes, maximizing the metabolic flux to a desired product. Here a genome-wide collection of native promoter libraries were constructed to drive the expression of a yellow fluorescent protein (YFP) reporter in Saccharomyces cerevisiae, allowing fast and accurate measurement of activity of each promoter with fluorescence activated cell sorting (FACS) followed by next-generation sequencing. Most important of all, the activity of these promoters under different growth conditions and in various host cells could be measured, which allows the identification of promoters specifically suitable for certain industrial applications. As a proof of principal, a set of promoters was selected to construct the metabolic pathway to increase ethanol production using xylose as carbon source. The same strategy could be applied to optimize the production of many other natural products.

Nov. 2016, Volume 10 Issue 4

(Renxing Wang, Zhenyu Liu, Leiming Ji, Xiaojin Guo, Xi Lin, Junfei Wu, Qingya Liu, pp. 517-525)
Production of calcium carbide (C_aC₂) from coal-derived coke and lime is still an important coal-to-chemical process today. The autothermal technologies with pulverized coke and lime or pelletized feed have been developed for this process in recent years to replace the traditional electric arc technology due to reduction in energy consumption and CO₂ emission. Reaction kinetics of these feeds required for simulation and design of reactors and process are limited and contradictive in the literature. Based on the reaction data obtained by TGA at 17001850°C applicable to industry, the kinetic model is determined with the isoconversional and model-fitting methods. It is found that the process is mainly influenced by heat transfer from the environment to the feed. The larger geometrical surface area of the powder feed yields a higher C_aC₂ formation rate in comparison with the pelletized feed. The reaction kinetics of both feeds can be described by the contracting volume model. The apparent activation energy and the pre-exponential factor of the pulverized feed are 353 kJ∙mol⁻¹ and 5.9 × 10⁷ min⁻¹, respectively, while those of the pelletized feed are 305 kJ∙mol⁻¹ and 3.6×10⁶ min⁻¹, respectively.

Aug. 2016, Volume 10 Issue 3

(Dae Hwan Shin, Yu Tong Tam, Glen S. Kwon, pp. 348-359)
Several amphiphilic block copolymers (ABCs) have been widely studied for drug solubilization that enables safe intravenous administration of anticancer drugs, including PEG-b-PLA, PEG-b-poly(propylene glycol)-b-PEG (i.e., Pluronics^®), PEG-b-poly(ε-caprolactone) (PEG-b-PCL) and PEG-b-poly(α-amino acid). Proven safety of ABCs is paramount for intravenous administration, along with other major requirements that include sterility, stability, solubility and scale-up. ABCs tend to disrupt cellular membranes less than low molecular weight surfactants, such as Cremophor EL, and undergo renal clearance that limits accumulation in the body, increasing safety. While the primary driving force for drug solubilization is hydrophobic interaction, polarity and hydrogen bonding play parts in governing interaction between drug and core region of polymeric micelles. Thus, structural diversity of core-forming blocks of ABCs permits drug solubilization of a variety of poorly water-soluble anticancer agents; for example, camptothecin, paclitaxel, resveratrol and valspodar, increasing water solubility by 10³-fold.

May. 2016, Volume 10 Issue 2

(Jasna Brčić, Janez Plavec, pp. 222-237)
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two related neurodegenerative diseases with devastating consequences. Largely increased number of GGGGCC repeats located within the first intron of C9orf72 gene was identified as the most frequent genetic cause of ALS and FTD. It was proposed that G-quadruplexes formed in the DNA strand of the expanded GGGGCC repeat cause transcriptional pausing and abortion, which leads to accumulation of abortive G-quadruplex forming RNA transcripts. In addition to RNA transcripts being toxic, evidence suggests that they can undergo RAN (repeat-associated non-ATG) translation producing potentially harmful dipeptide repeat proteins. Initial NMR investigation of DNA oligonucleotides with four repeat units chosen as the shortest model with the ability to form a unimolecular G-quadruplex indicated their folding into multiple G-quadruplex structures in the presence of K+ ions. We set to reduce the structural polymorphism by directing the folding towards the most stable naturally occurring G-quadruplex structure. Several approaches were used to drive a complex equilibrium, including point mutations, different folding conditions and use of conformationally constrained 8Br-dG residue. Oligonucleotide d[(G4C2)3GGBrGG] bearing a single dG to 8Br-dG substitution at position 21 formed a single G-quadruplex structure at pH 7.2, which allowed its unequivocal structure determination.

Feb. 2016, Volume 10 Issue 1

(Nadeen Al-Janabi, Abdullatif Alfutimie, Flor R. Siperstein, Xiaolei Fan, pp. 103-107)
Metal-organic frameworks (MOFs), as versatile and promising adsorbents, have attracted much attention for gas adsorption and separation due to their high adsorption capacity and tuneable structural/chemical properties. Coordinatively unsaturated divalent metal cations (or open metal sites, OMSs) in certain MOFs, e.g. unsaturated copper centres in Cu₃(BTC)₂ MOF, have been recognised as the attractive feature for gas adsorption. These OMSs render an exceptionally high surface density (e.g. ~3 OMSs per 100 A) leading to particularly high affinity to polar molecules such as water. Therefore, understanding the hydrothermal stability of MOFs with OMSs under appropriate conditions is necessary to enhance the uptake of MOFs for practical applications, e.g. the CO₂ capture from flue gases where ca. 7% H₂O is present. Here, a case study of water vapour adsorption on Cu₃(BTC)₂ MOF is conducted revealing its deformation dynamics under humid conditions. Comprehensive post-adsorption characterisation of materials provides evidence, for the first time, for the underlying mechanism of how the water vapour degrades MOFs with OMSs. The result of this research is crucial to guide the ultimate design of future MOFs with superior hydrothermal stability, while maintaining the properties of interest.

Nov. 2015, Volume 9 Issue 4

(Xinxiang Cao, Arash Mirjalili, James Wheeler, Wentao Xie, Ben W.-L. Jang, pp. 422-449)
Alumina supported Cu-Pd single atom alloy catalysts have been synthesized using galvanic replacement and simple traditional incipient wetness techniques. The single atom alloy structure is evidenced by the HAADF-STEM and H2-chemsorption results. These two techniques can be further used as complimentary methods to confirm the formation of other single atom alloys on common industrial supports. The Cu-Pd catalysts synthesized show excellent selectivity and good activity for the selective hydrogenation of acetylene in ethylene due to the unique function of alloyed single Pd atoms to dissociate hydrogen molecules and transferthem to the neighboring Cu atoms for selective hydrogenation.On the other hand, the overall performance, including catalytic stability,of Cu-Pd catalysts is strongly tied to the synthesis procedure dictating how single atom alloy structure is formed.

Sep. 2015, Volume 9 Issue 3

Special Issue dedicated to the 120^th anniversary of Tianjin University

Jul. 2015, Volume 9 Issue 2

(See Kathryn A. MUMFORD, Yue WU, Geoffrey W. STEVENS. pp 125-141)
 The capture of carbon dioxide (CO₂) from large point sources and subsequent storage underground, utilization for enhanced oil recovery processes or use in chemical synthesis, is essential if CO₂ emissions to the atmosphere are to be reduced in the short term. Amongst all CO₂ capture technologies currently available, solvent absorption is regarded as the most likely to be used in this large scale application, primarily due to the maturity of the technology and history of successful industrial application. Before widespread implementation is likely, the cost of CO₂ capture needs to be reduced. This will be achieved through the development of improved solvents that exhibit; higher CO₂ absorption capacities; faster reaction kinetics; limited degradation; and reduced regeneration energies. Here, a timely review of the progress of various solvents for the capture of CO₂, from the bench scale, to pilot scale and on to commercial scale installations is provided.

Apr. 2015, Volume 9 Issue 1

See Huali WANG, Hena FAROOQI, Jinwen CHEN, pp 64–76

Jan. 2015, Volume 8 Issue 4

Oct. 2014, Volume 8 Issue 3

May. 2014, Volume 8 Issue 2

Mar. 2014, Volume 8 Issue 1

Dec. 2013, Volume 7 Issue 4

Sep. 2013, Volume 7 Issue 3

Jun. 2013, Volume 7 Issue 2

Mar. 2013, Volume 7 Issue 1

Dec. 2012, Volume 6 Issue 4

Sep. 2012, Volume 6 Issue 3

Jun. 2012, Volume 6 Issue 2

Mar. 2012, Volume 6 Issue 1

Dec. 2011, Volume 5 Issue 4

Sep. 2011, Volume 5 Issue 3

Jun. 2011, Volume 5 Issue 2

Mar. 2011, Volume 5 Issue 1

Dec. 2010, Volume 4 Issue 4

Sep. 2010, Volume 4 Issue 3

Jun. 2010, Volume 4 Issue 2

Mar. 2010, Volume 4 Issue 1

Dec. 2009, Volume 3 Issue 4

Sep. 2009, Volume 3 Issue 3

Jun. 2009, Volume 3 Issue 2

Mar. 2009, Volume 3 Issue 1

Dec. 2008, Volume 2 Issue 4

Sep. 2008, Volume 2 Issue 3

Jun. 2008, Volume 2 Issue 2

Mar. 2008, Volume 2 Issue 1

Dec. 2007, Volume 1 Issue 4

Sep. 2007, Volume 1 Issue 3

Jun. 2007, Volume 1 Issue 2

Mar. 2007, Volume 1 Issue 1