中南大学学报（自然科学版）2016，Vol.47Issue(7)：2189-2195,7.DOI:10.11817/j.issn.1672-7207.2016.07.002
植物修复收获物热解制备生物炭过程中重金属的稳定性研究
Stabilization on heavy metals of biochar from phytoremediation harvested biomass in pyrolysis processing
摘要
Abstract
Considering that a large amounts of biomass harvested containing heavy metals will be produced by phytoremediation for metal contaminated soil, the harvested biomass of giant reed containing heavy metals was selected, and the stability and enrichment characteristics of As, Cd and Pb in the pyrolysis process for biochar were studied by adding chemicals. The results show that the heavy metals in biomass are mainly enriched in biochar, and the amount and speciation of heavy metals in biochar are affected deeply by temperature of pyrolysis, pyrolysis time, the kind and amount of chemicals added. The percentage of biochar arrives at 86%when biomass is pyrolysed for 0.5 h by adding 0.5%NaOH of 250 ℃. The optimized stability conditions for As in biochar is pyrolysed for 2.00 h by adding 2%NaOH at 300 ℃, and for Cd in biochar is pyrolysed for 0.50 h by adding 0.5%FeCl3 at 250 ℃, for Pb in biochar is pyrolysed for 1 h by adding 5%CaCO3 at 400 ℃, respectively. The specific surface area of biochar reaches 0.31 m2/mg by adding FeCl3 and the stability capacity of heavy metals in biochar significantly increases. According to the BCR sequentialextraction procedure, the speciation of As in biochar exists mainly in residual form from the pyrolysis by adding NaOH while those of As in biochar exists mainly in oxidizable form by adding CaCO3,Al2O3 and FeCl3. The speciation of Cd in biochar exists mainly in residual form, and that of Pb in biochar exists mainly in oxidizable form with adding stable agents including NaOH, CaCO3, Al2O3 and FeCl3.关键词
植物修复/芦竹收获物/热解/重金属Key words
phytoremediation/biomass harvested of giant reed/pyrolysis/heavy metal分类
资源环境引用本文复制引用
孙阳,刘亚男,郭朝晖,侍维..植物修复收获物热解制备生物炭过程中重金属的稳定性研究[J].中南大学学报（自然科学版）,2016,47(7):2189-2195,7.基金项目
国家自然科学基金资助项目(21577176，41271330)(Projects(21577176,41271330) supported by the National Natural Science Foundation of China) （21577176，41271330）
