Department of Chemical Engineering, Siirt University, Siirt, Turkey.
Department of Electrical &Electronics Engineering, Siirt University, Siirt, Turkey.
Environ Technol. 2021 Jan;42(3):505-520. doi: 10.1080/09593330.2020.1811397. Epub 2020 Aug 27.
In this study, char was prepared from the Şırnak coal derivative as a new adsorbent by the pyrolysis process and successfully applied for Pb (II) removal. Prepared char adsorbent was characterized by analysis techniques such as thermogravimetric (TG)/differential thermogravimetric (DTG), iodine number, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and Brunauer-Emmett-Teller (BET) surface area. In the experimental design of the Pb (II) removal process, the relationship between operating factors (contact time, initial Pb (II) concentration and temperature) and process responses (adsorption capacity and removal efficiency) was modelled by applying response surface methodology (RSM). After that, the operating factors for the maximum adsorption capacity and removal efficiency of Pb (II) by char were optimized. In the removal of Pb (II), pseudo-first order and pseudo-second order kinetic models were used to determine the process mechanism. In addition, adsorption isotherm models such as Langmuir, Freundlich, and Dubinin-Radushkevich were applied to the equilibrium data to explain the adsorption mechanism between the adsorbent and adsorbate molecules. According to the results obtained, it was determined that kinetic and equilibrium isotherm data were better defined with pseudo-second order kinetic and Dubinin-Radushkevich isotherm models, respectively. The optimum values of the contact time, initial Pb (II) concentration, and temperature for maximum adsorption capacity (124.64 mg/g) and removal efficiency (92.35%) of Pb (II) were found as 150.00 min, 144.81 ppm, and 35.06°C, respectively. This study indicated the application potential of Şırnak coal-derived char as a promising cost-effective adsorbent for the removal of heavy metals.
在这项研究中，通过热解过程，以Şırnak 煤衍生物为原料制备了炭，并将其成功应用于 Pb（II）的去除。通过热重（TG）/差示热重（DTG）、碘值、扫描电子显微镜（SEM）、傅里叶变换红外光谱（FT-IR）和 Brunauer-Emmett-Teller（BET）表面积等分析技术对制备的炭吸附剂进行了表征。在 Pb（II）去除过程的实验设计中，通过应用响应面法（RSM），对操作因素（接触时间、初始 Pb（II）浓度和温度）与过程响应（吸附容量和去除效率）之间的关系进行了建模。之后，对炭吸附 Pb（II）的最大吸附容量和去除效率的操作因素进行了优化。在去除 Pb（II）的过程中，采用了伪一级和伪二级动力学模型来确定反应机制。此外，还将 Langmuir、Freundlich 和 Dubinin-Radushkevich 等吸附等温线模型应用于平衡数据，以解释吸附剂与吸附质分子之间的吸附机制。根据获得的结果，确定动力学和平衡等温线数据分别用伪二级动力学和 Dubinin-Radushkevich 等温线模型更好地定义。对于最大吸附容量（124.64mg/g）和去除效率（92.35%），确定了接触时间、初始 Pb（II）浓度和温度的最佳值，分别为 150.00min、144.81ppm 和 35.06°C。本研究表明，Şırnak 煤衍生炭作为一种有前途的、具有成本效益的重金属去除吸附剂具有应用潜力。
