{"title":"In-situ electrochemical upcycling ammonia from wastewater-level nitrate with a natural hematite electrode: Regulation, performance, and application","authors":"Xing Wu, Zhenhui Song, Zhigong Liu, Xi Tang, Fubing Yao, Feiping Zhao, Xiaobo Min, Chong-Jian Tang","doi":"10.1016/j.apcatb.2024.124467","DOIUrl":null,"url":null,"abstract":"Electrochemical reduction of nitrate (NORR) to ammonia (NH/NH) offers promising prospects for NO treatment. However, this process still suffers from NH causing secondary pollution and catalyst deactivation in high-concentration NO wastewater. Herein, a high-performance system comprising a hematite (α-FeO) electrode and a water-resistant membrane achieved 97.6 % NO removal and 81.6 % NH as (NH)SO recovery at wastewater-level NO. The system exhibited an energy consumption of 62.2 kWh·Kg and a Faradaic efficiency of 85.9 %. spectroscopy and electrochemical measurements revealed that α-FeO acted as both an electron transfer mediator for reducing NO to NO and an active center for NH formation via NO/Fe(Ⅱ) redox. Density functional theory calculations identified *HNO to *NO as potential-determining step of NORR. Natural hematite-based system exhibited 74.8 % total inorganic nitrogen removal and 77.1 % NH recovery for actual photovoltaic wastewater. This study provides insights into the development of electrochemical systems for resourcefully treating NO-containing wastewater.","PeriodicalId":516528,"journal":{"name":"Applied Catalysis B: Environment and Energy","volume":"25 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Catalysis B: Environment and Energy","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1016/j.apcatb.2024.124467","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Electrochemical reduction of nitrate (NORR) to ammonia (NH/NH) offers promising prospects for NO treatment. However, this process still suffers from NH causing secondary pollution and catalyst deactivation in high-concentration NO wastewater. Herein, a high-performance system comprising a hematite (α-FeO) electrode and a water-resistant membrane achieved 97.6 % NO removal and 81.6 % NH as (NH)SO recovery at wastewater-level NO. The system exhibited an energy consumption of 62.2 kWh·Kg and a Faradaic efficiency of 85.9 %. spectroscopy and electrochemical measurements revealed that α-FeO acted as both an electron transfer mediator for reducing NO to NO and an active center for NH formation via NO/Fe(Ⅱ) redox. Density functional theory calculations identified *HNO to *NO as potential-determining step of NORR. Natural hematite-based system exhibited 74.8 % total inorganic nitrogen removal and 77.1 % NH recovery for actual photovoltaic wastewater. This study provides insights into the development of electrochemical systems for resourcefully treating NO-containing wastewater.