Selective photo-reduction of nitrate to nitrogen with a two-step process by a KBH_(4)/Cu(II)modified CuFe_(2)O_(4)photocatalyst  

作　　者：Li Cai Jinrui Guo Ting Liu Jing Tian Zhaoli Wang Yong Liu Mohamed SHamdy Xuping Sun 

机构地区：[1]College of Chemistry and Materials Science,Sichuan Normal University,Chengdu 610066,China [2]Chengdu Academy of Environmental Sciences,Chengdu 610072,China [3]Key Laboratory of Treatment for Special Wastewater of Sichuan Province Higher Education System,Chengdu 610066,China [4]Catalysis Research Group(CRG),Department of Chemistry,College of Science,King Khalid University,P.O.Box 9004,Abha 61413,Saudi Arabia [5]Institute of Fundamental and Frontier Sciences,University of Electronic Science and Technology of China,Chengdu 610054,China

出　　处：《Nano Research》2023年第7期10462-10475,共14页纳米研究（英文版）

基　　金：The research was financially supported by the National Natural Science Foundation of China(No.52070136);Applied Basic Research Project of Sichuan Science and Technology Department(No.21YYJC1289);The authors also extend their appreciation to the Deanship of Scientific Research at King Khalid University for funding support through large group Research Project(No.RGP2/199/44).

摘　　要：Nitrate(NO_(3)^(-))removal by photochemical-reduction has received extensive attention.However,the low selectivity of NO_(3)^(-)reduction to N_(2)hinders the application of this technology.In this study,a novel Cu@Fe-Cu-CuFe_(2)O_(4)-x photocatalyst was prepared by modifying CuFe_(2)O_(4)with KBH4 and Cu(II),and used to selectively reduce NO_(3)^(-)to N_(2)with a two-step reduction process.In step(1),with Cu@Fe-Cu-CuFe_(2)O_(4)-x/ultraviolet(UV)system,91.0%NO_(3)^(-)was reduced to 52.3%NO_(2)-and 39.4%N_(2)within 60 min.The rapid removal of NO_(3)^(-)was due to the synergistic effect of oxygen vacancies,Fe-Cu corrosion cell,and CuFe_(2)O_(4)photocatalysis.In step(2),H_(2)C_(2)O_(4)and H_(2)O_(2)were introduced into the effluent of step(1)to promote CO_(2)·-formation via Fe(II)and Fe(III)catalysis and UV radiation,which boosted the selective reduction of NO_(2)-to N_(2).When H_(2)C_(2)O_(4)and H_(2)O_(2)dosages were both 4.0 mmol·L^(-1)and the reaction time was 30 min,the removal efficiency of NO_(2)-achieved 100%and the selectivity of N_(2)was 83.0%.Overall,the two-step reduction process achieved 95.0%NO_(3)^(-)removal efficiency and 90.1%N_(2)selectivity with initial NO_(3)^(-)concentration of 30 mg·N·L^(-1).In addition,the denitrification mechanism of the two-step reduction process was tentatively proposed.

关 键 词：NITRATE NITRITE photochemical-reduction DENITRIFICATION photocatalysis 

分 类 号：O64[理学—物理化学]