铁基非晶合金对Cu污染土壤的还原固定  

Reduction and Immobilization of Fe-based Amorphous Alloy on Copper Contaminated Soil

作　　者：裴烈飞 袁子洲[2] Pei Liefei;Yuan Zizhou(Department of Mining and Metallurgical Engineering,Baiyin Mining and Metallurgical College;State Key Laboratory of Advanced Processing and Reuse of Nonferrous Metals,Lanzhou University of Technology)

机构地区：[1]白银矿冶职业技术学院矿冶工程学院 [2]兰州理工大学有色金属先进加工及再利用国家重点实验室

出　　处：《特种铸造及有色合金》2023年第3期354-359,共6页Special Casting & Nonferrous Alloys

基　　金：甘肃省教育厅高等学校创新基金资助项目(2021B-553)。

摘　　要：采用铁基非晶合金粉末Fe_(78)Si_(9)B_(13)固定化修复Cu污染土壤,探讨不同温度和pH值对Cu^(2+)形态转变的影响。动力学分析结果表明,Fe_(78)Si_(9)B_(13)AP与Cu^(2+)的反应均符合准一级动力学方程描述的规律,土壤总Cu含量为600 mg/kg,温度为3_(13) K,pH=6时,Fe_(78)Si_(9)B_(13)AP化学反应速率kobs=1.44_(9) h^(-1),活化能ΔE=15.94 kJ/mol。修复后土壤的三步浸提(BCR)结果显示,土壤中迁移态的Cu转变为可还原态和可氧化态,从而有效降低了土壤的环境风险。研究反应机理发现,Fe_(78)Si_(9)B_(13)AP的开路电压比零价Fe(ZVI)低0.27 V,因此在与Cu^(2+)的反应中具有更高的还原性。Fe_(78)Si_(9)B_(13)AP的产物层中存在大量疏松的孔道结构,有利于Cu^(2+)向反应界面的扩散从而保证反应的持续发生。Fe-based amorphous alloy powders(Fe_(78)Si_(9)Br_(13)^(AP))were adopted to immobilize and remediate copper-contaminated soil,and effects of temperatures and pH on morphological transformation of Cu^(2+)were investigated.The kinetic results indicate that the reaction of Fe_(78)Si_(9)Br13^(AP) and Cu^(2+)are consistent with the description of quasifirst-order dynamic equation.With the content of total copper in soil of 600 mg/kg,the temperature of 313 K and pH=6,the chemical reaction rate k_(obs) of Fe_(78)Si_(9)Br13^(AP) is 1.449 h^(-1),and the activation energy△E is 15.94 kJ/mol.The three-step leaching(BCR)results of soil after remediation reveal that the migratory copper in the soil is transformed into reducible and oxidizable states,thus effectively reducing the environmental risk of the soil.Reaction mechanism demonstrates that the open-circuit voltage of Fe_(78)Si_(9)Br13^(AP) is 0.27 V lower than ZVI,which exhibits higher reducibility in the reaction with Cu^(2+).There exists a large number of loose pore structures in the product layer of Fe_(78)Si_(9)Br13^(AP),which is conducive to the diffusion of Cu^(2+) to the reaction interface,ensuring the continuous occurrence of the reaction.

关 键 词：非晶合金 土壤修复 反应活性 还原固定 

分 类 号：TG1398[一般工业技术—材料科学与工程] X53[金属学及工艺—合金]