Biochar prepared from co-pyrolysis of municipal sewage sludge and tea waste for the adsorption of methylene blue from aqueous solutions: Kinetics, isotherm, thermodynamic and mechanism
Biochar prepared from co-pyrolysis of municipal sewage sludge and tea waste for the adsorption of methylene blue from aqueous solutions: Kinetics, isotherm, thermodynamic and mechanism
复制标题
DOI：
10.1016/j.molliq.2016.04.107
复制
发表时间：
2016-08-01
影响因子：
6
通讯作者：
Li, Xuede
中科院分区：
文献类型：
--
作者：
Fan, Shisuo;Tang, Jie;Li, Xuede
以城市污泥和茶叶废弃物为原料，通过共热解制备生物炭，并利用扫描电镜（SEM）和傅立叶变换红外光谱（FTIR）对生物炭进行表征。考察了投加量、接触时间、pH、温度等因素对生物炭吸附亚甲基蓝（MB）性能的影响。研究了吸附动力学、吸附等温线、吸附热力学和吸附机理。结果表明，亚甲基蓝在生物炭上的吸附符合准二级动力学模型。吸附等温线符合Langmuir吸附等温式，温度的升高促进了MB在气泡上的吸附。生物炭吸附亚甲基蓝的热力学研究表明，生物炭吸附亚甲基蓝是一个自发的吸热过程，在较高温度下表现出良好的自发性。同时，Δ S的正值表明生物炭吸附亚甲基蓝过程中固/液界面的随机性增加。MB与生物炭的作用机理涉及静电作用、离子交换、表面络合、物理作用等。这项工作表明，生物炭有望作为有效的吸附剂，以去除废水中的染料。(c)© 2016 Elsevier B. V.版权所有。
Biochar was generated from municipal sludge and tea waste through co-pyrolysisin this study and was characterized by Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The effect factors including dosage, contact time, pH, temperature on the adsorption properties of methylene blue (MB) onto biochar were investigated. The adsorption kinetics, isotherm, thermodynamic and mechanism also were also studied. The results showed that pseudo-second order kinetics was the most suitable model for describing the adsorption of MB onto biochar. Equilibrium data were well fitted to the Langmuir isotherm model.A rise in operating temperature enhances MB adsorption on blather. Adsorption thermodynamic of MB on biochar showed that the adsorption was a spontaneous and endothermic process and revealed'favorable spontaneous under higher temperature conditions. Meanwhile, the positive values of Delta S suggest the increased randomness at the solid/solution interface during the sorption of MB onto biochar. The mechanism between MB and biochar involved electrostatic interaction, ion exchange, surface complexation, physical function and others. This work shows that the biochar hold promises acting as effective adsorbent to remove dyes in the wastewater. (c) 2016 Elsevier B.V. All rights reserved.