Elevated efficiency in tartrazine removal from wastewater through boron-doped biochar: enhanced adsorption and persulfate activation

Abstract

Boron-doped biochar (B-BC) was synthesized by pyrolysis using solid waste of sorghum straw as raw material. The specific surface area of B-BC increased significantly by 2.38 times compared to that of pure BC. This enhancement allowed B-BC (0.3 g L⁻¹) to achieve complete adsorption of 10 mg L⁻¹ tartrazine (TTZ) within 40 min. Moreover, acidic conditions were more favorable for TTZ adsorption, achieving complete removal of TTZ in only 15 min at a pH of 3.0. Interestingly, the adsorption rate of TTZ by B-BC in the presence of 0.05 M Cl⁻ was approximately 2.12 times higher than that in the absence of Cl⁻. When other background electrolytes were present, excluding PO₄ ³⁻, complete adsorption of TTZ could also be achieved within 60 min. Thermodynamic analysis and DFT calculations described the parameters of B-BC for TTZ adsorption, including

\mathrm{\Delta }{\text{G}}^{\mathrm{\Theta }}

\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\Delta {\text{G}}^{\Theta }$$\end{document}

(< 0 kJ mol⁻¹),

\mathrm{\Delta }{\text{H}}^{\mathrm{\Theta }}

\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\Delta {\text{H}}^{\Theta }$$\end{document}

(− 2.199 kJ mol⁻¹),

\mathrm{\Delta }{\text{S}}^{\mathrm{\Theta }}

\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\Delta {\text{S}}^{\Theta }$$\end{document}

(− 6.068 J mol⁻¹ K⁻¹), and the adsorption energy (E _ads = − 0.6919 eV), indicating a tendency towards a spontaneous adsorption process. Moreover, the strong electron transfer ability of B-BC and the oxygen-containing groups promoted the activation of PDS and generation of active substances such as ¹O₂, O₂ ^•−, and SO₄ ^•−, thereby degrading TTZ into products with lower biological toxicity. When the added PDS was only 0.1 mM, the degradation rate constant of TTZ could reach 0.1481 min⁻¹. Furthermore, boron doping enhanced the stability of biochar, enabling the complete removal of 10 mg L⁻¹ TTZ even after recycling and regeneration. In summary, this study offers a practical solution for the resource utilization of solid waste sorghum straw and the treatment of TTZ-polluted wastewater.

Highlights

•	Boron doping significantly increased the specific surface area of biochar by 2.38 times.
•	B-BC exhibited complete adsorption of TTZ in only 15 min at a pH of 3.0.
•	Addition of 0.05 M Cl− increased the adsorption rate of TTZ on B-BC by 1.12 times.
•	Free radicals and nonradicals contributed to TTZ degradation in B-BC/PDS system.
•	Degradation products of TTZ displayed reduced toxicity to typical aquatic organisms.

Keywords

Sorghum straw / Boron doping / DFT / Degradation / Wastewater treatment / Peroxydisulfate

References

[2] Ajikashile JO, Alhnidi MJ, Bishir M, Kruse A. The influence of torrefaction temperature and reaction time on the properties of torrefied sun-dried millet and sorghum straws from the arid and semi-arid zones of western Africa. Biofuels Bioprod Biorefin, 2023, 17(3): 751-767,

[3] Akpomie KG, Conradie J. Banana peel as a biosorbent for the decontamination of water pollutants. A review. Environ Chem Lett, 2020, 18(4): 1085-1112,

[4] Amchova P, Kotolova H, Ruda-Kucerova J. Health safety issues of synthetic food colorants. Regul Toxicol Pharmacol, 2015, 73(3): 914-922,

[5] Balu S, Velmurugan S, Palanisamy S, Chen SW, Velusamy V, Yang TCK, El-Said IES. Synthesis of α-Fe₂O₃ decorated g-C₃N₄/ZnO ternary Z-scheme photocatalyst for degradation of tartrazine dye in aqueous media. J Taiwan Inst Chem Eng, 2019, 99: 258-267,

[6] Bhaumik R, Mondal NK. Optimizing adsorption of fluoride from water by modified banana peel dust using response surface modelling approach. Appl Water Sci, 2014, 6(2): 115-135,

[7] Cai C, Zhang H, Zhong X, Hou L. Ultrasound enhanced heterogeneous activation of peroxymonosulfate by a bimetallic Fe-Co/SBA-15 catalyst for the degradation of Orange II in water. J Hazard Mater, 2015, 283: 70-79,

[8] Cai S, Zhang Q, Wang Z, Hua S, Zhang R. Pyrrolic N-rich biochar without exogenous nitrogen doping as a functional material for bisphenol A removal: performance and mechanism. Appl Catal B: Environ, 2021, 291: 120093,

[9] Candice E, Manuel GP, Mullen CA, Yadav MP. Thermochemical behavior of alkali pretreated biomass—a thermogravimetric and Py-GC/FID study. Sustain Energy Fuels, 2023, 7(14): 3306-3315,

[10] Chaikittisilp W, Hu M, Wang H, Huang HS, Fujita T, Wu KC, Chen LC, Yamauchi Y, Ariga K. Nanoporous carbons through direct carbonization of a zeolitic imidazolate framework for supercapacitor electrodes. Chem Commun, 2012, 48(58): 7259-7261,

[11] Chen Y, Liu J, Zeng Q, Liang Z, Ye X, Lv Y, Liu M. Preparation of Eucommia ulmoides lignin-based high-performance biochar containing sulfonic group: synergistic pyrolysis mechanism and tetracycline hydrochloride adsorption. Bioresour Technol, 2021, 329: 124856,

[12] Chen HB, Gao YR, Li JH, Fang Z, Bolan N, Bhatnagar A, Gao B, Hou DY, Wang SS, Song H, Yang X, Shaheen SM, Meng J, Chen WF, Rinnklebe J, Wang HL. Engineered biochar for environmental decontamination in aquatic and soil systems: a review. Carbon Res, 2022, 1: 4,

[13] Chen XJ, Zhou Y, Li JS, Pillai SC, Bolan N, He JH, Li N, Xu S, Chen X, Lin QH, Wang HL. Activated peroxydisulfate by sorghum straw-based biochar for enhanced tartrazine degradation: Roles of adsorption and radical/nonradical processes. Environ Pollut, 2022, 316: 120665,

[14] Chen XJ, Xu ZP, Chen JM, Yao L, Xie WC, He JH, Li N, Li JS, Xu S, Zhu YP, Chen X, Zhu RL. Continuous surface Z-Scheme and Schottky heterojunction Au/La₂Ti₂O₇/Ag₃PO₄ catalyst with boosted charge separation through dual channels for excellent photocatalysis: highlight influence factors regulation and catalytic system applicability. Sep Purif Technol, 2023, 312: 123414,

[15] Chen C, Sun H, Zhang S, Su X. Structure-property relationship and mechanism of peroxymonosulfate activation by nitrogen-doped biochar for organic contaminant oxidation. Appl Surf Sci, 2023, 609: 155294,

[16] Cheng X, Guo HG, Zhang YL, Xu X, Liu Y. Non-photochemical production of singlet oxygen via activation of persulfate by carbon nanotubes. Water Res, 2017, 113: 80-88,

[17] Cheng Y, Wang B, Shen J, Yan P, Kang J, Wang W, Bi L, Zhu X, Li Y, Wang S. Preparation of novel N-doped biochar and its high adsorption capacity for atrazine based on π–π electron donor-acceptor interaction. J Hazard Mater, 2022, 432: 128757,

[18] Chukwuemeka-Okorie HO, Ekuma FK, Akpomie KG, Nnaji JC, Okereafor AG. Adsorption of tartrazine and sunset yellow anionic dyes onto activated carbon derived from cassava sievate biomass. Appl Water Sci, 2021, 11: 27,

[19] Dalanta F, Kusworo TD. Synergistic adsorption and photocatalytic properties of AC/TiO₂/CeO₂ composite for phenol and ammonia-nitrogen compound degradations from petroleum refinery wastewater. Chem Engineer J, 2022, 434: 134687,

[20] Dawodu MO, Akpomie KG. Evaluating the potential of a Nigerian soil as an adsorbent for tartrazine dye: isotherm, kinetic and thermodynamic studies. Alexandria Eng J, 2016, 55(4): 3211-3218,

[21] Dong X, Duan X, Sun Z, Zhang X, Li C, Yang S, Ren B, Zheng S, Dionysiou DD. Natural illite-based ultrafine cobalt oxide with abundant oxygen-vacancies for highly efficient Fenton-like catalysis. Appl Catal B Environ, 2020, 261: 118214,

[22] Dung NT, Duong LT, Hoa NT, Thao VD, Ngan LV, Huy NN. A comprehensive study on the heterogeneous electro-Fenton degradation of tartrazine in water using CoFe₂O₄/carbon felt cathode. Chemosphere, 2022, 287: 132141,

[23] Gao Y, Zhu Y, Lyu L, Zeng Q, Xing X, Hu C. Electronic structure modulation of graphitic carbon nitride by oxygen doping for enhanced catalytic degradation of organic pollutants through peroxymonosulfate activation. Environ Sci Technol, 2018, 52(24): 14371-14380,

[24] Gao T, Shi W, Zhao M, Huang Z, Liu X, Ruan W. Preparation of spiramycin fermentation residue derived biochar for effective adsorption of spiramycin from wastewater. Chemosphere, 2022, 296: 133902,

[25] Gasim MF, Lim JW, Low SC, Lin KA, Oh WD. Can biochar and hydrochar be used as sustainable catalyst for persulfate activation?. Chemosphere, 2022, 287(4): 132458,

[26] Gratuito MK, Panyathanmaporn T, Chumnanklang RA, Sirinuntawittaya N, Dutta A. Production of activated carbon from coconut shell: optimization using response surface methodology. Bioresour Technol, 2008, 99(11): 4887-4895,

[27] Hamadeen HM, Elkhatib EA. New nanostructured activated biochar for effective removal of antibiotic ciprofloxacin from wastewater: adsorption dynamics and mechanisms. Environ Res, 2022, 210: 112929,

[28] Hayyan M, Hashim MA, Alnashef IM. Superoxide ion: generation and chemical implications. Chem Rev, 2017, 116(5): 3029-3085,

[29] Hernandes PT, Franco DSP, Georgin J, Salau NPG, Dotto GL. Investigation of biochar from Cedrella fissilis applied to the adsorption of atrazine herbicide from an aqueous medium. J Environ Chem Eng, 2022, 10(3): 107408,

[30] Ji L, Cheng Q, Wu K, Yang X. Cu-BTC frameworks-based electrochemical sensing platform for rapid and simple determination of Sunset yellow and Tartrazine. Sens Actuators B, 2016, 231: 12-17,

[31] Jiang SY, Xu W, Xia Q, Yi M, Zhou YR, Shang JW, Cheng XW. Application of machine learning in the study of cobalt-based oxide catalysts for antibiotic degradation: an innovative reverse synthesis strategy. J Hazard Mater, 2024, 471: 134309,

[32] Kaya SI, Cetinkaya A, Ozkan SA. Latest advances on the nanomaterials-based electrochemical analysis of azo toxic dyes Sunset Yellow and Tartrazine in food samples. Food Chem Toxicol, 2021, 156: 112524,

[33] Lee J, von Gunten U, Kim JH. Persulfate-based advanced oxidation: critical assessment of opportunities and roadblocks. Environ Sci Technol, 2020, 54(6): 3064-3081,

[34] Li X, Liu J, Rykov AI, Han H, Jin C, Liu X, Wang J. Excellent photo-Fenton catalysts of Fe-Co Prussian blue analogues and their reaction mechanism study. Appl Catal B Environ, 2015, 179: 196-205,

[35] Li C, Wu H, Zhu D, Zhou T, Yan M, Chen G, Sun J, Dai G, Ge F, Dong H. High-efficient charge separation driven directionally by pyridine rings grafted on carbon nitride edge for boosting photocatalytic hydrogen evolution. Appl Catal B Environ, 2021, 297: 120433,

[36] Li K, Ma S, Xu S, Fu H, Li Z, Li Y, Liu S, Du J. The mechanism changes during bisphenol A degradation in three iron functionalized biochar/peroxymonosulfate systems: The crucial roles of iron contents and graphitized carbon layers. J Hazard Mater, 2021, 404,

[37] Liu B, Guo W, Wang H, Si Q, Ren N. B-doped graphitic porous biochar with enhanced surface affinity and electron transfer for efficient peroxydisulfate activation. Chem Eng J, 2020, 396: 125119,

[38] Liu J, Jia H, Mei M, Wang T, Chen S, Li J. Efficient degradation of diclofenac by digestate-derived biochar catalyzed peroxymonosulfate oxidation: performance, machine learning prediction, and mechanism. Process Saf Environ Prot, 2022, 167: 77-88,

[39] Liu D, Li K, Zhou L. N, O co-doping enhanced the ability of carbon/Fe composites for peroxymonosulfate activation to degrade sulfadiazine: the advantages of nitrate saturated MOFs as precursors. Sep Purif Technol, 2023, 314: 123556,

[40] Luo Z, Xu Y, Tang D. Electron-transfer based selective oxidation of organic pollutants via N-doped biochar activated peroxydisulfate: Important role of oxidation potential. Sep Purif Technol, 2023, 326: 124769,

[41] Ma P, Qi Z, Wu X, Ji R, Chen W. Biochar nanoparticles-mediated transport of organic contaminants in porous media: dependency on contaminant properties and effects of biochar aging. Carbon Res, 2023, 2: 4,

[42] Ndi Nsami J, Ketcha Mbadcam J. The adsorption efficiency of chemically prepared activated carbon from cola nut shells by on methylene blue. J Chem, 2013, 2013: 469170,

[43] Ouassif H, Moujahid EM, Lahkale R, Sadik R, Bouragba FZ, Sabbar EM, Diouri M. Zinc-Aluminum layered double hydroxide: high efficient removal by adsorption of tartrazine dye from aqueous solution. Surf Interfaces, 2020, 18: 2468-3230,

[44] Palas B, Ersöz G, Atalay S. Photo Fenton-like oxidation of Tartrazine under visible and UV light irradiation in the presence of LaCuO₃ perovskite catalyst. Process Saf Environ Prot, 2017, 111: 270-282,

[45] Priyadarshini MB, Lopamudra A, Kulamani P. Synergistic effect of exfoliation and substitutional doping in graphitic carbon nitride for photocatalytic H₂O₂ production and H₂ generation: a comparison and kinetic study. Catal Sci Technol, 2023, 13(5): 1448-1458,

[46] Qiu TH, Li CX, Guang MM, Zhang YN. Porous carbon material production from microwave-assisted pyrolysis of peanut shell. Carbon Res, 2023, 2: 45,

[47] Qu S, Yuan Y, Yang X, Xu H, Mohamed AK, Zhang J, Zhao C, Liu L, Wang B, Wang X, Rinklebe J, Li YC, Wang S. Carbon defects in biochar facilitated nitrogen doping: the significant role of pyridinic nitrogen in peroxymonosulfate activation and ciprofloxacin degradation. Chem Eng J, 2022, 441: 135864,

[48] Ren J, Jiang X, Han X, Yang K, Cai H. Delignified sorghum straw/PEG/EP phase change composites: combining biomass source, form-stabilities, and high performances. Mater Lett, 2023, 349: 134799,

[49] Shakoor MB, Ye ZL, Chen S. Engineered biochars for recovering phosphate and ammonium from wastewater: a review. Sci Total Environ, 2021, 779: 146240,

[50] Shi S, Jia C, Huo X, Zhang S, Xu Q, Zhu X. Thermal stabilization effect and oxygen replacement reaction together regulate N/S co-doped microporous carbon synthesis. Carbon Res, 2022, 1: 7,

[51] Shi W, Wang H, Yan J, Shan L, Quan G, Pan X, Cui L. Wheat straw derived biochar with hierarchically porous structure for bisphenol A removal: preparation, characterization, and adsorption properties. Sep Purif Technol, 2022, 289: 120796,

[52] Singh L, Rekha P, Chand S. Cu-impregnated zeolite Y as highly active and stable heterogeneous Fenton-like catalyst for degradation of Congo red dye. Sep Purif Technol, 2016, 170: 321-336,

[53] Srinivasan S, Sadasivam SK. Biodegradation of textile azo dyes by textile effluent non-adapted and adapted Aeromonas hydrophila. Environ Res, 2021, 194: 110643,

[54] Sujana MG, Anand S. Fluoride removal studies from contaminated ground water by using bauxite. Desalination, 2011, 267(2–3): 222-227,

[55] Sun F, Qu Z, Gao J, Wu HB, Liu F, Han R, Wang L, Pei T, Zhao G, Lu Y. In situ doping boron atoms into porous carbon nanoparticles with increased oxygen graft enhances both affinity and durability toward electrolyte for greatly improved supercapacitive performance. Adv Funct Mater, 2018, 28(41): 1804190,

[56] Sun Z, Zhao L, Liu C, Zhen Y, Ma J. Fast adsorption of BPA with high capacity based on π-π electron donor-acceptor and hydrophobicity mechanism using an in-situ sp2 C dominant N-doped carbon. Chem Eng J, 2020, 381,

[57] Sun YT, Gu YT, Li MY, Wang HQ, Hu C, Lyu L. Fast elimination of emerging contaminates in complicated water environment medium over the resource conversion product of chicken manure biochar triggered by peroxymonosulfate. Carbon Res, 2024, 3: 8,

[58] Suo N, Huang H, Wang X, Hou X, Shao Z, Zhang G. Facile synthesis and electrocatalytic performance for oxygen reduction of boron-doped carbon catalysts on graphene sheets. Fuel Cells, 2021, 21(3): 328-336,

[60] Thue PS, Umpierres CS, Lima EC, Lima DR, Machado FM, dos Reis GS, da Silva RS, Pavan FA, Hai NT. Single-step pyrolysis for producing magnetic activated carbon from tucum (Astrocaryum aculeatum ) seed and nickel(II) chloride and zinc(II) chloride. Application for removal of nicotinamide and propanolol. J Hazard Mater, 2020, 398(5): 122903,

[61] Vu AT, Xuan TN, Lee CH. Preparation of mesoporous Fe₂O₃·SiO₂ composite from rice husk as an efficient heterogeneous Fenton-like catalyst for degradation of organic dyes. J Water Process Eng, 2019, 28: 169-180,

[62] Wachter N, Aquino JM, Denadai M, Barreiro JC, Rocha-Filho RC. Electrochemical degradation of the antibiotic ciprofloxacin in a flow reactor using distinct BDD anodes: Reaction kinetics, identification and toxicity of the degradation products. Chemosphere, 2019, 234: 461-470,

[63] Wang Z, Jang HM. Comparative study on characteristics and mechanism of levofloxacin adsorption on swine manure biochar. Bioresour Technol, 2022, 351: 127025,

[64] Wang RZ, Huang DL, Liu YG, Zhang C, Xu P. Synergistic removal of copper and tetracycline from aqueous solution by steam-activated bamboo-derived biochar. J Hazard Mater, 2019, 384: 121470,

[65] Wang Y, Jiao WB, Wang JT, Liu GF, Cao HL, Lu J. Amino-functionalized biomass-derived porous carbons with enhanced aqueous adsorption affinity and sensitivity of sulfonamide antibiotics. Bioresour Technol, 2019, 277: 128-135,

[66] Wang CQ, Huang R, Sun RR, Yang JP, Sillanpa M. A review on persulfates activation by functional biochar for organic contaminants removal: synthesis, characterizations, radical determination, and mechanism. J Environ Chem Eng, 2021, 9: 106267,

[67] Wang C, Holm PE, Andersen ML, Thygesen LG, Nielsen UG, Hansen HCB. Phosphorus doped cyanobacterial biochar catalyzes efficient persulfate oxidation of the antibiotic norfloxacin. Bioresour Technol, 2023, 388: 129785,

[68] Xie J, Luo X, Chen L, Gong X, Zhang L, Tian J. ZIF-8 derived boron, nitrogen co-doped porous carbon as metal-free peroxymonosulfate activator for tetracycline hydrochloride degradation: performance, mechanism and biotoxicity. Chem Eng J, 2022, 440: 135760,

[69] Xie J, Liu M, Li J, Yu F, Liu Y, Lv Y, Lin C, Ye X, He M. Ultra-efficient adsorption of diclofenac sodium on fish-scale biochar functionalized with H₃PO₄ via synergistic mechanisms. Environ Pollut, 2023, 322: 121226,

[70] Xu L, Wu C, Liu P, Bai X, Wang Y. Peroxymonosulfate activation by nitrogen-doped biochar from sawdust for the efficient degradation of organic pollutants. Chem Eng J, 2020, 387: 124065,

[71] Xu C, Chen J, Li S, Gu Q, Wang D, Jiang C, Liu Y. N-doped honeycomb-like porous carbon derived from biomass as an efficient carbocatalyst for H2S selective oxidation. J Hazard Mater, 2021, 403: 123806,

[72] Xu C, Tan X, Zhao J, Cao J, Ren M, Xiao Y, Lin A. Optimization of biochar production based on environmental risk and remediation performance: take kitchen waste for example. J Hazard Mater, 2021, 416: 125785,

[73] Xu P, Wang P, Li X, Wei R, Wang X, Yang C, Shen T, Zheng T, Zhang G. Efficient peroxymonosulfate activation by CuO-Fe₂O₃/MXene composite for atrazine degradation: performance, coexisting matter influence and mechanism. Chem Eng J, 2022, 440: 135863,

[74] Yamjala K, Nainar MS, Ramisetti NR. Methods for the analysis of azo dyes employed in food industry-A review. Food Chem, 2016, 192: 813-824,

[75] Yang J, Pan B, Li H, Liao S, Zhang D, Wu M, Xing B. Degradation of p-Nitrophenol on biochars: role of persistent free radicals. Environ Sci Technol, 2016, 50(2): 694-700,

[76] Yang H, Guo X, Chen R, Liu Q, Liu J, Yu J, Lin C, Wang J, Zhang M. Enhanced anti-biofouling ability of polyurethane anti-cavitation coating with ZIF-8: a comparative study of various sizes of ZIF-8 on coating. Eur Polym J, 2021, 144: 110212,

[77] Yang B, Dai J, Zhao Y, Wu J, Ji C, Zhang Y. Advances in preparation, application in contaminant removal, and environmental risks of biochar-based catalysts: a review. Biochar, 2022, 4: 51,

[78] Yao B, Luo Z, Du S, Yang J, Zhi D, Zhou Y. Sustainable biochar/MgFe₂O₄ adsorbent for levofloxacin removal: adsorption performances and mechanisms. Bioresour Technol, 2021,

[79] Yi Y, Huang Z, Lu B, Xian J, Tsang EP, Cheng W, Fang J, Fang Z. Magnetic biochar for environmental remediation: a review. Bioresour Technol, 2020, 298: 122468,

[80] Yin Q, Yan H, Liang Y. Nitrogen doped biochar derived from algae as persulfate activator for the degradation of tetracycline: role of exogenous N doping and electron transfer pathway. Sep Purif Technol, 2023, 318: 123970,

[81] Yuan H, Shi W, Lu J. Dual-channels separated mechanism of photo-generated charges over semiconductor photocatalyst for hydrogen evolution: interfacial charge transfer and transport dynamics insight. Chem Eng J, 2023, 454: 140442,

[82] Zeng H, Zeng H, Zhang H, Shahab A, Ullah H. Efficient adsorption of Cr(VI) from aqueous environments by phosphoric acid activated eucalyptus biochar. J Cleaner Prod, 2020, 286: 124964,

[83] Zhang J, Shao X, Shi C, Yang S. Decolorization of Acid Orange 7 with peroxymonosulfate oxidation catalyzed by granular activated carbon. Chem Eng J, 2013, 301: 1-11,

[84] Zhang C, Ren G, Wang W, Yu X, Yu F, Zhang Q, Zhou M. A new type of continuous-flow heterogeneous electro-Fenton reactor for Tartrazine degradation. Sep Purif Technol, 2019, 208: 76-82,

[85] Zhang H, Li L, Li Y, He R, Li H, Yu Y. N and S co-doped pine needle biochar activated peroxydisulfate for antibiotic degradation. J Cleaner Prod, 2022, 379: 134619,

[86] Zhang XX, Bhattacharya T, Wang CQ, Kumar A, Nidheesh PV. Straw-derived biochar for the removal of antibiotics from water: adsorption and degradation mechanisms, recent advancements and challenges. Environ Res, 2023, 237: 116998,

[87] Zhang XX, Huang R, Show PL, Mahlknecht J, Wang CQ. Degradation of tetracycline by nitrogen-doped biochar as a peroxydisulfate activator: nitrogen doping pattern and non-radical mechanism. Sustain Horizons, 2024, 10: 100091,

[88] Zhong Q, Lin Q, He W, Fu H, Huang Z, Wang Y, Wu L. Study on the nonradical pathways of nitrogen-doped biochar activating persulfate for tetracycline degradation. Sep Purif Technol, 2021, 276(2): 119354,

[89] Zhu SS, Li XJ, Kang J, Duan XG, Wang SB. Persulfate activation on crystallographic manganese oxides: mechanism of singlet oxygen evolution for nonradical selective degradation of aqueous contaminants. Environ Sci Technol, 2018,

[90] Zhu S, Huang X, Ma F, Wang L, Duan X, Wang S. Catalytic removal of aqueous contaminants on n-doped graphitic biochars: inherent roles of adsorption and nonradical mechanisms. Environ Sci Technol, 2018, 52(15): 8649-8658,

[91] Zhu M, Kong L, Xie M, Lu W, Liu H, Li N, Feng Z, Zhan J. Carbon aerogel from forestry biomass as a peroxymonosulfate activator for organic contaminants degradation. J Hazard Mater, 2021, 413: 125438,

Funding

Natural Science Foundation of Guangdong Province, China(2022A1515010333); Guangdong Basic and Applied Basic Research Foundation(2022A1515140122); National Natural Science Foundation of China(42377245); Guangdong Foundation for Program of Science and Technology Research, China(2023B1212060044)