Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, State Environmental Protection Key Laboratory of Soil Health and Green Remediation, College of Resources and Environment, Shenzhen Institute of Nutrition and Health, Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China; Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.
Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, State Environmental Protection Key Laboratory of Soil Health and Green Remediation, College of Resources and Environment, Shenzhen Institute of Nutrition and Health, Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China; Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.
Environ Pollut. 2022 Oct 1;310:119869. doi: 10.1016/j.envpol.2022.119869. Epub 2022 Aug 1.
In general, the remediation performance of heavy metals can be further improved by metal-oxide modified biochar. This work used MgO-modified rice husk biochar (MgO-5%@RHB-450 and MgO-5%@RHB-600) with high surface activity for simultaneous remediation and removal of heavy metals in soil and wastewater. The adsorption of MgO-5%@RHB-450/MgO-5%@RHB-600 for Cd(II), Cu(II), Zn(II) and Cr(VI) followed the pseudo-second order, with the adsorption capacities reaching 91.13/104.68, 166.68/173.22, 80.12/104.38 and 38.88/47.02 mg g, respectively. The addition of 1.0% MgO-5%@RHB-450 and MgO-5%@RHB-600 could effectively decrease the CaCl-extractable Cd concentration (CaCl-Cd) by 66.2% and 70.0%, respectively. Moreover, MgO-5%@RHB-450 and MgO-5%@RHB-600 facilitated the transformation of exchangeable fractions to carbonate-bound and residual fractions, and reduced the exchangeable fractions by 8.1% and 9.6%, respectively. The mechanisms for the removal of heavy metals from wastewater by MgO-5%@RHB-450 and MgO-5%@RHB-600 mainly included complexation, ion exchange and precipitation, and the immobilization mechanisms in soil may be precipitation, complexation and pore filling. In general, this study provides high-efficiency functional materials for the remediation of heavy metal pollution.
一般来说，金属氧化物改性生物炭可以进一步提高重金属的修复性能。本工作使用表面活性高的 MgO 改性稻壳生物炭（MgO-5%@RHB-450 和 MgO-5%@RHB-600），同时修复和去除土壤和废水中的重金属。MgO-5%@RHB-450/MgO-5%@RHB-600 对 Cd(II)、Cu(II)、Zn(II) 和 Cr(VI) 的吸附符合准二级动力学，吸附容量分别达到 91.13/104.68、166.68/173.22、80.12/104.38 和 38.88/47.02 mg g。添加 1.0% MgO-5%@RHB-450 和 MgO-5%@RHB-600 可分别有效降低 66.2%和 70.0%的 CaCl 可提取 Cd 浓度（CaCl-Cd）。此外，MgO-5%@RHB-450 和 MgO-5%@RHB-600 促进了可交换态向碳酸盐结合态和残留态的转化，分别降低了 8.1%和 9.6%的可交换态。MgO-5%@RHB-450 和 MgO-5%@RHB-600 从废水中去除重金属的机制主要包括络合、离子交换和沉淀，在土壤中的固定机制可能是沉淀、络合和孔填充。总的来说，本研究为重金属污染修复提供了高效的功能材料。
