SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China; School of Environment, South China Normal University, University Town, Guangzhou 510006, China.
SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China; School of Environment, South China Normal University, University Town, Guangzhou 510006, China.
J Environ Sci (China). 2023 May;127:564-576. doi: 10.1016/j.jes.2022.06.009. Epub 2022 Jun 19.
The wastes generated from the mining and processing of granite and marble stone are generally regarded as useless. However, these waste materials were used as the soil amendments for the first time. The functional groups, crystalline structure and micro-morphology of granite and marble wastes amendments (GMWA) were different from the original wastes demonstrated by X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FT-IR) and Scanning electron microscope-energy dispersive spectrometer (SEM-EDS) analyses. With the addition of the amendments, the cation exchange capacity, electrical conductivity and nutrient availability of the soil increased, and the extractable heavy metals of the soil reduced significantly. Under the condition of the addition of 3% amendments, 7.0%, 99.9%, 99.7% and 70.5% of Cu, Pb, Zn and Cd in exchangeable fractions in soil were transformed to the more stable Fe-Mn oxides- or carbonates-bounded fractions. Tessier method and correlation analysis showed that the reduction of extractable metals in the acidic paddy soil can be attributed to the adsorption of available SiO, the co-precipitation induced by the elevated pH value, the complexation induced by Fe-Mn oxides and the cation exchange induced by mineral nutrients. This study provides a new strategy for resource recovery of waste stones and remediation of heavy metal-contaminated soil.
花岗石和大理石矿采和加工过程中产生的废物通常被视为无用之物。然而，这些废料首次被用作土壤改良剂。X 射线衍射仪（XRD）、傅里叶变换红外光谱仪（FT-IR）和扫描电子显微镜-能谱仪（SEM-EDS）分析表明，花岗石和大理石废物改良剂（GMWA）的官能团、晶体结构和微观形貌与原始废物不同。随着改良剂的添加，土壤的阳离子交换容量、电导率和养分有效性增加，土壤中可提取的重金属显著减少。在添加 3%改良剂的条件下，土壤中交换态的 Cu、Pb、Zn 和 Cd 有 7.0%、99.9%、99.7%和 70.5%转化为更稳定的 Fe-Mn 氧化物或碳酸盐结合态。Tessier 方法和相关性分析表明，酸性稻田土壤中可提取金属的减少归因于有效 SiO 的吸附、pH 值升高引起的共沉淀、Fe-Mn 氧化物诱导的络合以及矿质养分诱导的阳离子交换。本研究为废石资源回收和重金属污染土壤修复提供了新策略。
