When zero-valent iron(ZVI)is prepared and applied under neutral conditions,it is easy to form oxides or hydroxides on its surface,which hinders the electron release of ZVI.To this end,a nucleophile was introduced into...When zero-valent iron(ZVI)is prepared and applied under neutral conditions,it is easy to form oxides or hydroxides on its surface,which hinders the electron release of ZVI.To this end,a nucleophile was introduced into the ZVI system to inhibit the precipitation of iron ions,improve the conductivity of the solution,and promote the removal efficiency of electrophilic functional groups in organic compounds.In this study,the addition of nucleophiles such as ethylenediamine,methylamine and dimethylamine to the ZVI/H_(2)O_(2)system resulted in an enhanced removal efficiency of tetracycline(TC)under neutral condition,while electrophiles such as EDTA-2Na and oxalic acid dihydrate impeded the removal of TC.Experimental results demonstrated that the presence of nucleophiles could effectively promote the release of iron ions and increase the proportion of ferrous in both aqueous solution and solid surface of ZVI.Experimental and theoretical calculation results revealed that the electrophilic functional group was eliminated in the TC molecule,and the toxicity of the treated solution was reduced significantly.Overall,this work provides a selection of the conditions and pollutants applicable to ZVI under neutral pH conditions.展开更多
基金financial support from Sichuan Science and Technology Program(No.2023NSFSC0345)the Fundamental Research Funds for the Central Universities(Southwest Minzu University,No.ZYN2022002)+1 种基金the Innovation Scientific Research Program for Graduates of Southwest Minzu University(Southwest Minzu University,No.3300222156)the China Scholarship Council(No.202008510077)。
文摘When zero-valent iron(ZVI)is prepared and applied under neutral conditions,it is easy to form oxides or hydroxides on its surface,which hinders the electron release of ZVI.To this end,a nucleophile was introduced into the ZVI system to inhibit the precipitation of iron ions,improve the conductivity of the solution,and promote the removal efficiency of electrophilic functional groups in organic compounds.In this study,the addition of nucleophiles such as ethylenediamine,methylamine and dimethylamine to the ZVI/H_(2)O_(2)system resulted in an enhanced removal efficiency of tetracycline(TC)under neutral condition,while electrophiles such as EDTA-2Na and oxalic acid dihydrate impeded the removal of TC.Experimental results demonstrated that the presence of nucleophiles could effectively promote the release of iron ions and increase the proportion of ferrous in both aqueous solution and solid surface of ZVI.Experimental and theoretical calculation results revealed that the electrophilic functional group was eliminated in the TC molecule,and the toxicity of the treated solution was reduced significantly.Overall,this work provides a selection of the conditions and pollutants applicable to ZVI under neutral pH conditions.
