Shi Qingliang, Zhang Hua, Shahab Asfandyar, Zeng Honghu, Zeng Huiting, Bacha Aziz-Ur-Rahim, Nabi Iqra, Siddique Jamil, Ullah Habib
Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China.
Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China; Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst, Area, Guilin University of Technology, Guilin 541004, China.
Ecotoxicol Environ Saf. 2021 Sep 15;221:112426. doi: 10.1016/j.ecoenv.2021.112426. Epub 2021 Jun 21.
Lead (Pb) and cadmium (Cd) are considered as a typical heavy metals in aqueous solution, which may pose adverse health effects on human beings. For the removal of these two pollutants, magnesium oxide (MgO) was successfully immobilized onto eucalyptus biochar (BC) matrix via simple and cost-effective pyrolysis process of MgCl-pretreated eucalyptus biomass under high temperature (500 °C). Synthesized MgO nanoparticles-biochar composites (MBC) exhibited superior removal performance for target pollutants, and achieve 99.9% removal efficiency for Pb(II) and Cd(II) at optimum conditions (0.02 g, pH in range of 4-7, and reaction time 120, 240 min). Furthermore, the maximum theoretical adsorbing amount of MBC was 829.11 mg/g for Pb(II) and 515.17 mg/g for Cd(II). Pseudo-second-order model and Langmuir models were well-determined for isotherm and adsorption kinetics. FTIR, XRD, and XPS analysis revealed that precipitation and ion exchange was of great importance for the removal of contaminants. Besides, cation-π interaction and complexation from the carbon-containing functional groups should not be neglected. Considering the advantage of low-cost, facile preparation, and brilliant adsorption capacity, it is anticipated that MBC has a promising prospect for the broad application in Pb(II)/Cd(II)-containing wastewater treatment.
铅（Pb）和镉（Cd）被认为是水溶液中的典型重金属，可能会对人类健康造成不利影响。为了去除这两种污染物，通过在高温（500°C）下对MgCl预处理的桉木生物质进行简单且经济高效的热解过程，成功地将氧化镁（MgO）固定在桉木生物炭（BC）基质上。合成的MgO纳米颗粒-生物炭复合材料（MBC）对目标污染物表现出优异的去除性能，在最佳条件（0.02 g，pH值在4-7范围内，反应时间120、240分钟）下，对Pb（II）和Cd（II）的去除效率达到99.9%。此外，MBC对Pb（II）的最大理论吸附量为829.11 mg/g，对Cd（II）为515.17 mg/g。等温线和吸附动力学的伪二级模型和朗缪尔模型得到了很好的确定。傅里叶变换红外光谱（FTIR）、X射线衍射（XRD）和X射线光电子能谱（XPS）分析表明，沉淀和离子交换对污染物的去除非常重要。此外，含碳官能团的阳离子-π相互作用和络合作用也不容忽视。考虑到低成本、制备简便和出色的吸附能力等优点，预计MBC在含Pb（II）/Cd（II）废水处理中的广泛应用具有广阔的前景。
