Electrocatalytic reduction of nitrate using Pd-Cu modified carbon nanotube membranes  

作　　者：Zhijun Liu Xi Luo Senlin Shao Xue Xia 

机构地区：[1]College of Life and Environmental Sciences,Minzu University of China,Beijing 100081,China [2]School of Civil Engineering,Wuhan University,Wuhan 430072,China [3]Yangtze Ecology and Environment Co.,Ltd.,Wuhan 430062,China

出　　处：《Frontiers of Environmental Science & Engineering》2023年第4期1-11,共11页环境科学与工程前沿（英文）

基　　金：This work was supported by grants from the National Natural Science Foundation of China(Nos.52070147 and 52270077);the Special Fund of the State Key Joint Laboratory of Environment Simulation and Pollution Control(No.22K06ESPCT);the Promotion Plan for Young Teachers’Scientific Research Ability of Minzu University of China(Nos.2021QNPY83 and 2022QNPY51).

摘　　要：Excessive nitrate in water is harmful to the ecological environment and human health.Electrocatalytic reduction is a promising technology for nitrate removal.Herein,a Pd-Cu modified carbon nanotube membrane was fabricated with an electrodeposition method and used to reduce nitrate in a flowthrough electrochemical reactor.The optimal potential and duration for codeposition of Pd and Cu were-0.7 V and 5 min,respectively,according to linear scan voltammetry results.The membrane obtained with a Pd:Cu ratio of 1:1 exhibited a relatively high nitrate removal efficiency and N_(2)selectivity.Nitrate was almost completely reduced(~99%)by the membrane at potentials lower than-1.2 V.However,-0.8 V was the optimal potential for nitrate reduction in terms of both nitrate removal efficiency and product selectivity.The nitrate removal efficiency was 56.2%,and the N_(2)selectivity was 23.8%for the Pd:Cu=1:1 membrane operated at-0.8 V.Nitrate removal was enhanced under acidic conditions,while N_(2)selectivity was decreased.The concentrations of Cl-ions and dissolved oxygen showed little effect on nitrate reduction.The mass transfer rate constant was greatly improved by 6.6 times from 1.14×10^(-3)m/h at a membrane flux of 1 L/(m^(2)·h)to 8.71×10^(-3)m/h at a membrane flux of 15 L/(m^(2)·h),which resulted in a significant increase in the nitrate removal rate from 13.6 to 133.5 mg/(m^(2)·h).These findings show that the Pd-Cu modified CNT membrane is an efficient material for nitrate reduction.

关 键 词：Pd-Cu modified CNT membrane Nitrate reduction FLOW-THROUGH ELECTRODEPOSITION Electrocatalytic reduction 

分 类 号：TB383[一般工业技术—材料科学与工程]