Wang An, Wang Yao, Zhao Peng, Huang Zhanbin
School of Chemical and Environmental Engineering, China University of Mining and Technology-Beijing, Beijing, 100083, China.
School of Chemical and Environmental Engineering, China University of Mining and Technology-Beijing, Beijing, 100083, China.
Environ Pollut. 2022 Sep 15;309:119812. doi: 10.1016/j.envpol.2022.119812. Epub 2022 Jul 20.
Passivation of soil heavy metals using environmental materials is an important method or important in situ remediation measure. There are more studies on inorganic environmental materials for heavy metal passivation, but not enough studies on organic and their composite environmental materials with inorganic ones. In order to reveal the passivation effect of coal-based ammoniated humic acid (CAHA), biochemical humic acid (BHA), biochar (BC) and other organic types and inorganic environmental materials such as zeolites (ZL) on soil heavy metals and their biological effectiveness. The microstructures of these materials were analyzed by Scanning electron microscope (SEM). The main components of the environmental materials were analyzed by Energy dispersive spectrometer (EDS), Fourier transforms infrared spectroscopy (FT-IR) and X-ray diffraction spectrum (XRD) to elucidate the mechanism of passivation of heavy metals in soil by these environmental materials. The study was conducted to investigate the effects of different types of environmental materials and their combinations on the passivation effect and biological effectiveness of Pb and Cd complex contamination in soil by means of soil incubation and pot experiments using single-factor and multifactor multilevel orthogonal experimental designs. Soil incubation experiments proved that the effective state of soil Pb and Cd in T was reduced by 13.40% and 11.07%, respectively. The extreme difference analysis determined the optimized formulation of soil lead and cadmium passivation as BHA: CAHA: BC: ZL = 3.5:5:20:10. The pot experiment proved that the application of composite environmental materials led to the reduction of lead and cadmium content and increase of biomass of Pak-choi, and the optimal dosage of optimized composite environmental materials was 23.1 g/kg.
利用环境材料钝化土壤重金属是一种重要的方法或原位修复措施。目前关于无机环境材料钝化重金属的研究较多，但有机环境材料及其与无机材料的复合环境材料的研究还不够充分。为揭示煤基氨化腐殖酸（CAHA）、生化腐殖酸（BHA）、生物炭（BC）等有机类环境材料以及沸石（ZL）等无机环境材料对土壤重金属及其生物有效性的钝化效果，通过扫描电子显微镜（SEM）分析了这些材料的微观结构，利用能谱仪（EDS）、傅里叶变换红外光谱仪（FT-IR）和X射线衍射光谱仪（XRD）分析了环境材料的主要成分，以阐明这些环境材料对土壤中重金属的钝化机制。本研究采用单因素和多因素多水平正交试验设计，通过土壤培养和盆栽试验，研究了不同类型环境材料及其组合对土壤中铅镉复合污染钝化效果和生物有效性的影响。土壤培养试验表明，处理T中土壤铅和镉的有效态含量分别降低了13.40%和11.07%。极差分析确定了土壤铅镉钝化的优化配方为BHA:CAHA:BC:ZL = 3.5:5:20:10。盆栽试验表明，施用复合环境材料可降低小白菜铅镉含量，增加生物量，优化复合环境材料的最佳施用量为23.1 g/kg。
