Reducing agent for heavy metal contaminated soil and use method thereof

The invention discloses a reducing agent for heavy metal contaminated soil and a using method of the reducing agent. The reducing agent for the heavy metal contaminated soil comprises organic matter compost and modified nanoscale zero-valent iron according to the mass ratio of (4-10): (0.1-0.6). The modified nano zero-valent iron is prepared from the following components in parts by mass: 3-5 parts of iron salt; 3-6 parts of a reducing agent; 2-4 parts of a stabilizer; 100 to 200 parts of an alcoholic solution; 1 to 3 parts of a silane coupling agent; and 1 to 2 parts of dimercaptothreitol. The reducing agent for the heavy metal contaminated soil is free of generation of by-products harmful to human health in the using process, and the remediation effect is outstanding. 本申请公开了一种重金属污染土壤用还原剂及其使用方法，该重金属污染土壤用还原剂包括质量比为(4～10):(0.1～0.6)的有机质堆肥和改性纳米零价铁；所述改性纳米零价铁由包括如下质量份的组分制得：铁盐：3～5份；还原剂：3～6份；稳定剂：2～4份；醇溶液：100～200份；硅烷偶联剂：1～3份；二巯基苏糖醇：1～2份。本申请的重金属污染土壤用还原剂在使用过程中无危害人体健康的副产物生成，且修复效果较为突出。