Advanced Materials Group, Materials Sciences and Technology Division, CSIR-North East Institute of Science and Technology, Jorhat, Assam, India; Academy of Scientific and Innovative Research, CSIR-NEIST Campus, Jorhat, Assam, India.
Center for Nanobiology and Structural Biology, Institute of Microbiology of the Czech Academy of Sciences, Zámek 136, Nové Hrady, Czech Republic; Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic.
J Environ Manage. 2021 Apr 1;283:111989. doi: 10.1016/j.jenvman.2021.111989. Epub 2021 Jan 27.
Experimental and computational investigations have been conducted in this study to assess the influence of municipal waste pyrolyzed biochar impregnated clay composites on antibiotic removal as a material for wastewater treatment and simultaneous value-addition for waste. The surface potential (zeta potential) of the pristine biochar and composite samples are found to be within the range ~10 to ~ -40 mV in the pH range 2-10. The presence of different inorganic salt solutions influences the electrophoretic mobility of the dispersed phase in a suspension, as well as its zeta potential. In addition of Na salt solutions, the Na ions undergo electrostatic interaction with the negatively charged biochar samples and form a double layer at the interface of biochar and ionic salt solution. Molecular dynamics simulations have been employed to understand experimental findings, ions adsorption and solute-solvent interactions at the molecular level of two biochar B7 (seven benzene rings, one methoxy, one aldehyde and two hydroxyls groups) and B17 (seventeen benzene rings, one methoxy, two hydroxyls and two carboxylic acid groups) in salts aqueous solutions. The results confirm that hydroxyls and carboxylate groups of biochar are responsible for solute-solvent interactions. Successful removal of tetracycline antibiotics is observed with 26 mg/g maximum adsorption capacity with montmorillonite biochar composite. This study confirms that interactions between amide and hydroxyl groups of tetracycline with hydroxyl and carboxylate groups of biochar play the key role in the adsorption process. The solution pH and presence of different background electrolytes effectively influence the process of solute-solvent interactions as well as adsorption efficacy towards tetracycline adsorption.
本研究通过实验和计算研究了市政垃圾热解生物炭浸渍粘土复合材料对抗生素去除的影响，该复合材料可作为废水处理材料，同时实现废物的附加值。原始生物炭和复合样品的表面电位（zeta 电位）在 pH 值 2-10 范围内处于10 到-40 mV 之间。不同无机盐溶液的存在会影响悬浮液中分散相的电泳迁移率及其 zeta 电位。除了 Na 盐溶液外，Na 离子还与带负电荷的生物炭样品发生静电相互作用，并在生物炭和离子盐溶液界面形成双电层。分子动力学模拟已被用于从分子水平理解实验结果、离子吸附和溶质-溶剂相互作用，研究了两种生物炭 B7（七个苯环、一个甲氧基、一个醛基和两个羟基）和 B17（十七个苯环、一个甲氧基、两个羟基和两个羧基）在盐水溶液中的情况。结果证实，生物炭的羟基和羧基基团负责溶质-溶剂相互作用。蒙脱土生物炭复合材料对四环素抗生素的最大吸附容量为 26mg/g，实现了四环素的有效去除。本研究证实，四环素的酰胺和羟基与生物炭的羟基和羧基基团之间的相互作用在吸附过程中起着关键作用。溶液 pH 值和不同背景电解质的存在有效地影响了溶质-溶剂相互作用的过程以及对四环素吸附的吸附效果。
