Dynamic Adsorption of Toluene on Hierarchical Porous Carbons with Varying Pore Structure

Abstract

Hierarchical porous carbon material (MMC) was successfully fabricated via hard template synthesis method by carbonization of furfury alcohol within the template (MCM-41). The prepared MMC was studied with characterization methods including scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption-desorption analyses, and infrared spectral analysis (FTIR). To investigate kinetics of toluene adsorption of hierarchical porous carbon materials, the adsorption performances of these carbon samples with varying pore structure (MC-1, MMC, MMHPC) were analyzed via dynamic adsorption. And the Langmuir model and Freundlich equation were employed to correspond with adsorption isotherms to study the adsorption mechanism. The experimental results demonstrate that the Langmuir model is more appropriate to describe the adsorption process. The capacities of toluene adsorption follow the order of MMC < MMHPC (micro-meso hierarchical porous carbon) < MC-1(microporous carbon). MC-1 has satisfactory absorption performance due to its large pore volume and high ratio of micropores. MMHPC has excellent toluene adsorption performance for proper amounts of surface oxygen containing groups. Long saturation time, interconnected hierarchical pore channels, and large specific surface area make MMC also a promising material for VOCs treatment. These data reveal that the pore channel structure, rational pore distribution, high surface area and reasonable amounts of surface oxygen groups are the main factors contributed to excellent toluene adsorption performance, which proposes theoretical basis for hierarchical porous carbon materials to further engineering application.

Keywords

hierarchical porous carbon / toluene / adsorption / pore structure

References

[1] Wang Q. Multifractal Characterization of Air Polluted Time Series in China[J]. Physica A: Statistical Mechanics and Its Applications, 2019, 514: 167-180.

[2] Zhu J, Zhang P, Wang Y, et al. Effect of Acid Activation of Palygorskite on Their Toluene Adsorption Behaviors[J]. Applied Clay Science, 2018, 159: 60-70.

[3] Gu X, Su Z, Xi H. New Activated Carbon with High Thermal Conductivity and Its Microwave Regeneration Performance[J]. Journal of Wuhan University of Technology-Mater. Sci. Ed., 2016, 31(2): 328-333.

[4] Wang Y, Su X, Wen K, et al. Preparation of Surface-functionalized Porous Clay Heterostructures via Carbonization of Soft-template and Their Adsorption Performance for Toluene[J]. Applied Surface Science, 2016, 363: 113-121.

[5] Dumont E, Darracq G, Couvert A, et al. Volumetric Mass Transfer Coefficients Characterising VOC Absorption in Water/Silicone Oil Mixtures[J]. Chemical Engineering Journal, 2013, 221: 308-314.

[6] Ozturk B, Kuru C, Aykac H, et al. VOC Separation using Immobilized Liquid Membranes Impregnated with Oils[J]. Separation & Purification Technology, 2015, 153: 1-6.

[7] Nigar H, Julian I, Mallada R, et al. Microwave-assisted Catalytic Combustion for the Efficient Continuous Cleaning of VOC-containing Air Streams[J]. Environmental Science & Technology, 2018, 52(10): 5 892-5 901.

[8] Cheng Y, He H, Yang C, et al. Challenges and Solutions for Biofiltration of Hydrophobic Volatile Organic Compounds[J]. Biotechnology Advances, 2016, 34: 1 091-1 102.

[9] Feng C, Wang F, Liu P, et al. Photocatalytic Activity of Porous Magnesium Oxychloride Cement Combined with AC/TiO₂ Composites[J]. Journal of Wuhan University of Technology-Mater. Sci. Ed., 2017, 32(3): 591-597.

[10] Niknaddaf S, Atkinson JD, Shariaty P, et al. Heel Formation during Volatile Organic Compound Desorption from Activated Carbon Fiber Cloth[J]. Carbon, 2016, 96: 131-138.

[11] Yang X, Yi H, Tang X, et al. Behaviors and Kinetics of Toluene Adsorption-desorption on Activated Carbons with Varying Pore Structure[J]. Journal of Environmental Sciences, 2018, 67(5): 104-114.

[12] Qiu W, Dou K, Zhou Y, et al. Hierarchical Pore Structure of Activated Carbon Fabricated by CO/Microwave for Volatile Organic Compounds Adsorption[J]. Chinese Journal of Chemical Engineering, 2018, 26: 81-88.

[13] Zhou H, Gao S, Zhang W, et al. Dynamic Adsorption of Toluene on Amino-functionalized SBA-15 Type Spherical Mesoporous Silica[J]. RSC Advances, 2019, 9(13): 7 196-7 202.

[14] Yan X, Liu F, Mu G, et al. Adsorption of Toluene Vapours on Micromeso Hierarchical Porous Carbon[J]. Micro & Nano Letters, 2018, 13(5): 641-645.

[15] Yan X, Liu F, Zhao C, et al. Application of Micro-meso Hierarchical Porous Carbon for Toluene Adsorption Treatment[J]. Micro & Nano Letters, 2016, 11(7): 372-377.

[16] Gregg SJ, Sing KSW. Adsorption, Surface Area and Porosity[M], 1982 London: Academic Press. 220 63

[17] Lo A, Hung C, Yu N, et al. Syntheses of Carbon Porous Materials with Varied Pore Sizes and Their Performances as Catalyst Supports during Methanol Oxidation Reaction[J]. Clean Energy for Future Generations, 2012, 100(4): 66-74.

[18] Wibowo N, Setyadhi L, Wibowo D, et al. Adsorption of Benzene and Toluene from Aqueous Solutions onto Activated Carbon and Its Acid and Heat Treated Forms: Influence of Surface Chemistry on Adsorption[J]. Journal of Hazardous Materials, 2007, 146(1–2): 237-242.

[19] Payer KR, Hammond KD, Tompsett GA, et al. The Effects of Mechanical and Thermal Perturbations on States within the Hysteresis of Sorption Isotherms of Mesoporous Materials[J]. J. Porous Mater., 2009, 16(1): 91-99.

[20] Adib F, Bagreev A, Bandosz TJ. Analysis of the Relationship between H₂S Removal Capacity and Surface Properties of Unimpregnated Activated Carbons[J]. Environ. Sci. Technol., 2000, 34(4): 686-692.

[21] Schepetkin AI, Khlebnikov IA, Ah YS, et al. Characterization and Biological Activities of Humic Substances from Mumie[J]. J Agric Food Chem., 2003, 51(18): 5 245-5 254.

[22] Chen PJ, Wu S. Acid/base-treated Carbons: Characterization of Functional Groups and Metal Adsorption Properties[J]. Langmuir, 2004, 20(6): 2 233-2 242.

[23] Chingombe P, Saha B, Wakeman RJ. Surface Modification and Characterisation of a Coal-based Activated Carbon[J]. Carbon, 2005, 43(15): 3 132-3 143.

[24] Kruk M, Jaroniec M, Sayari A. Relations between Pore Structure Parameters and Their Implications for Characterization of Mcm-41 using Gas Adsorption and X-ray Diffraction[J]. Chem. Materials, 1999, 11(2): 492-500.

[25] Lillo-Ródenas MA, Cazorla-Amorós D, Linares-Solano A. Behaviour of Activated Carbons with Different Pore Size Distributions and Surface Oxygen Groups for Benzene and Toluene Adsorption at Low Concentrations [J]. Carbon, 2005, 43(8): 1 758-1 767.

[26] García T, Murillo R, Cazorla-Amorós D, et al. Role of the Activated Carbon Surface Chemistry in the Adsorption of Phenanthrene[J]. Carbon, 2004, 42(8): 1 683-1 689.

[27] Baur G B, Beswick O, Spring J, et al. Activated Carbon Fibers for Efficient VOC Removal from Diluted Streams: The Role of Surface Functionalities[J]. Adsorption, 2015, 21(4): 479-488.

[28] Song Y, Qiao W, Seong-Ho Y, et al. Toluene Adsorption on Various Activated Carbons with Different Pore Structures[J]. New Carbon Materials, 2015, 20(4): 294-298.

[29] Li L, Song J, Yao X, et al. Adsorption of Volatile Organic Compounds on Three Activated Carbon Samples: Effect of Pore Structure[J]. J. Cent. South Univ., 2012, 19(12): 3 530-3 539.

[30] Fytianos K, Voudrias E, Kokkalis E. Sorption-desorption Behavior of 2, 4-dichloriphenol by Marine Sediments[J]. Chemosphere, 2000, 40(1): 3-6.