College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi, 712100, China.
College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi, 712100, China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture and Rural Affairs of the People's Republic of China, Yangling, 712100, China.
Chemosphere. 2022 Feb;289:133251. doi: 10.1016/j.chemosphere.2021.133251. Epub 2021 Dec 9.
Production of cost-efficient composite materials from low-cost modified biochar for the removal of Cd (II) from wastewater is much needed to meet the growing needs of industrial wastewater treatments. A novel chitosan-modified kiwi branch biochar (CHKB) was fabricated as low-cost modified biochar for the removal of Cd (II) from aqueous solution. Batch adsorption and characterization experiments indicated that the modification of kiwi biochar (KB) by chitosan remarkably improved its adsorption performance. The results revealed that the adsorption isotherms can be best described by a Langmuir model and that a pseudo-second-order model fits the Cd (II) adsorption kinetics well, which indicates that it is a monolayer process controlled by chemisorption. CHKB exhibited a Langmuir maximum adsorption capacity of Cd (II) (126.58 mg g), whereas that of KB was only 4.26 mg g. The adsorption ability of CHKB was improved by increasing the surface area and an abundance of surface functional groups (-OH, -NH, CO, etc.). The cation exchange, electrostatic interaction, surface complexation, and precipitation were the main mechanisms in the sorption of Cd (II) on CHKB. Excellent adsorption performance, low cost, and environmental-friendliness made CHKB a fantastic adsorbent for the removal of Cd (II) in wastewater.
从低成本改性生物炭中生产具有成本效益的复合材料，以去除废水中的 Cd(II)，这对于满足工业废水处理日益增长的需求非常重要。本文制备了一种新型壳聚糖改性猕猴桃枝生物炭（CHKB），作为从水溶液中去除 Cd(II) 的低成本改性生物炭。批量吸附和特性实验表明，壳聚糖对猕猴桃生物炭（KB）的改性显著提高了其吸附性能。结果表明，吸附等温线可以用朗缪尔模型很好地描述，而准二级模型很好地拟合了 Cd(II)的吸附动力学，这表明它是一个受化学吸附控制的单层过程。CHKB 对 Cd(II)的朗缪尔最大吸附容量为 126.58mg/g，而 KB 仅为 4.26mg/g。通过增加表面积和丰富的表面官能团（-OH、-NH、CO 等），提高了 CHKB 的吸附能力。阳离子交换、静电相互作用、表面络合和沉淀是 Cd(II)在 CHKB 上吸附的主要机制。CHKB 具有优异的吸附性能、低成本和环境友好性，是去除废水中 Cd(II)的理想吸附剂。
