Lin Peng-Cheng, Yin Hua, Liu Xiao-Fei, Liu Hang, Yan Cai-Ya, Qi Xin
School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China.
Huan Jing Ke Xue. 2023 Feb 8;44(2):975-983. doi: 10.13227/j.hjkx.202202219.
The combined pollution of heavy metal Cu and Cd in soil induced by the e-waste dismantling process has become a severe problem. To deal with this issue, crab shell biochar (BC) and Mn/Al-layered double oxide-loaded crab shell biochar (LDO/BC) were prepared using coprecipitation and co-pyrolysis of discarded crab shells and manganese aluminum salt. The experimental results showed that not only were the soil pH, available phosphorus, available potassium, and soil enzymatic activity enhanced, but the contents of DTPA-Cu and DTPA-Cd in the soil were also reduced after remediation by BC and LDO/BC. Microbial community analysis indicated that BC-1% could promote the relative abundance of Gemmatimonadota and Acidobacteriota; meanwhile, LDO/BC-1% could promote the relative abundance of Proteobacteria, which could reduce the accumulation of Cd in plants. Ryegrass was planted for further investigating the toxic effect of heavy metals in soil after remediation. The results demonstrated that after remediating with BC-5% and LDO/BC-1%, ryegrass grew more vigorously and with a lower content of the heavy metals Cu and Cd in the plants than that of CK, and the germination rate increased by 29% and 60%, respectively. Further, LDO/BC-1% had a more excellent remediation performance than that of the other groups, and the Mn in LDO/BC could reduce the content of heavy metal Cd adsorbed by ryegrass in soil.
电子废弃物拆解过程导致的土壤中重金属铜和镉的复合污染已成为一个严峻问题。为解决这一问题，采用废弃蟹壳与锰铝盐的共沉淀和共热解方法制备了蟹壳生物炭（BC）和负载锰/铝层状双氢氧化物的蟹壳生物炭（LDO/BC）。实验结果表明，BC和LDO/BC修复后，不仅提高了土壤pH值、有效磷、有效钾和土壤酶活性，还降低了土壤中DTPA-Cu和DTPA-Cd的含量。微生物群落分析表明，BC-1%能促进芽单胞菌门和酸杆菌门的相对丰度；同时，LDO/BC-1%能促进变形菌门的相对丰度，这有助于减少植物中镉的积累。种植黑麦草以进一步研究修复后土壤中重金属的毒性效应。结果表明，用BC-5%和LDO/BC-1%修复后，黑麦草生长更旺盛，植物中重金属铜和镉的含量低于对照，发芽率分别提高了29%和60%。此外，LDO/BC-1%的修复性能优于其他组，LDO/BC中的锰能降低土壤中黑麦草吸附的重金属镉含量。
