Centre for Technological Excellence in Water Purification, Department of Chemical Engineering, National Institute of Technology Durgapur, Durgapur, India.
Department of Chemical Engineering, Jadavpur University, Kolkata, India.
Environ Sci Pollut Res Int. 2020 Jun;27(17):20629-20647. doi: 10.1007/s11356-019-06014-z. Epub 2019 Aug 5.
The current study emphasises on sorptive expulsion of phenol from aqueous solution using ortho-phosphoric acid (STAC-O) and sulphuric acid (STAC-H)-activated biochar derived from spent tea waste. STAC-O and STAC-H were instrumentally anatomised using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), BET surface area and thermal gravimetric analyser. Equilibrium and kinetic data were implemented for the investigative parametric batch study to prospect the influence of adsorbent dosage, contact time, initial concentration and pH for eradication of phenol from aqueous solution. The maximum phenolic removals by STAC-O and STAC-H are 93.59% and 91.024% respectively at the parametric conditions of adsorbent dosage 3 g/l time 2 h, initial phenol concentration 100 mg/l and pH 8. Non-linear regression of adsorption isotherms and kinetics was accomplished using the equilibrium data. Both the specimens were compared, and it delineated that Temkin isotherm model is contented. The maximum adsorption intakes for STAC-H and STAC-O were 185.002 mg/g and 154.39 mg/g respectively. Pseudo-second-order kinetic model was best fitted for portraying the chemisorption phenomena. Boyd kinetic and intra-particle diffusion model were investigated to elucidate the diffusion mechanism involved in the process. Desorption study was employed for determining the regeneration proficiency of the adsorbents using water, ethanol and NaOH with maximum 93% and 51.16% extrusion for STAC-O and STAC-H respectively. The process parameters involved in this study were further analysed using artificial neural network perusal to determine the input-output relationships and data pattern. The overall adsorption study along with cost estimation exhibited that bidirectional activation of spent tea biochar was prospective in abatement of phenol from aqueous media.
本研究强调了使用邻磷酸（STAC-O）和硫酸（STAC-H）对从废茶中衍生的生物炭进行吸附解吸以去除水溶液中的苯酚。使用扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）、X 射线衍射（XRD）、BET 表面积和热重分析仪对 STAC-O 和 STAC-H 进行了仪器分析。进行了平衡和动力学数据分析，以研究吸附剂剂量、接触时间、初始浓度和 pH 值对从水溶液中去除苯酚的影响。在吸附剂剂量 3 g/l、时间 2 h、初始苯酚浓度 100 mg/l 和 pH 8 的参数条件下，STAC-O 和 STAC-H 的最大苯酚去除率分别为 93.59%和 91.024%。使用平衡数据完成了吸附等温线和动力学的非线性回归。对两个样本进行了比较，结果表明，Temkin 等温模型是满意的。STAC-H 和 STAC-O 的最大吸附量分别为 185.002 mg/g 和 154.39 mg/g。准二级动力学模型最适合描述化学吸附现象。研究了 Boyd 动力学和内扩散模型，以阐明过程中涉及的扩散机制。通过使用水、乙醇和 NaOH 进行解吸研究，以确定吸附剂的再生效率，STAC-O 和 STAC-H 的最大解吸率分别为 93%和 51.16%。进一步使用人工神经网络分析了本研究中的过程参数，以确定输入-输出关系和数据模式。总的吸附研究以及成本估算表明，双向激活废茶生物炭在从水介质中去除苯酚方面具有前景。
