Microbial electrosynthesis of acetate from CO_(2)under hypersaline conditions  

作　　者：Xiaoting Zhang Tyler Arbour Daijun Zhang Shiqiang Wei Korneel Rabaey 

机构地区：[1]College of Resources and Environment,Southwest University,Chongqing,400715,China [2]Center for Microbial Ecology and Technology(CMET),Ghent University,Coupure Links 653,9000,Ghent,Belgium [3]State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing,400044,China [4]Center for Advanced Process Technology for Urban Resource Recovery(CAPTURE),Frieda Saeysstraat 1,9052,Ghent,Belgium

出　　处：《Environmental Science and Ecotechnology》2023年第1期86-95,共10页环境科学与生态技术（英文）

基　　金：supported by the National Natural Science Foundation of China(No.42107242 and 51974039);Chongqing Special Support Fund for Post Doctor;supported by a Competitive Research Grant from the Office of Sponsored Research(No.OSR-2016-CRG5-2985)of King Abdullah University of Science and Technology.

摘　　要：Microbial electrosynthesis(MES)enables the bioproduction of multicarbon compounds from CO_(2)using electricity as the driver.Although high salinity can improve the energetic performance of bioelectrochemical systems,acetogenic processes under elevated salinity are poorly known.Here MES under 35e60 g L^(-1)salinity was evaluated.Acetate production in two-chamber MES systems at 35 g L^(-1)salinity(seawater composition)gradually decreased within 60 days,both under-1.2 V cathode potential(vs.Ag/AgCl)and^(-1).56 A m^(-2)reductive current.Carbonate precipitation on cathodes(mostly CaCO3)likely declined the production through inhibiting CO_(2)supply,the direct electrode contact for acetogens and H2 production.Upon decreasing Ca2t and Mg2t levels in three-chamber reactors,acetate was stably produced over 137 days along with a low cathode apparent resistance at 1.9±0.6 mU m^(2)and an average production rate at 3.80±0.21 g m^(-2)d^(-1).Increasing the salinity step-wise from 35 to 60 g L^(-1)gave the most efficient acetate production at 40 g L^(-1)salinity with average rates of acetate production and CO_(2)consumption at 4.56±3.09 and 7.02±4.75 g m^(-2)d^(-1),respectively.The instantaneous coulombic efficiency for VFA averaged 55.1±31.4%.Acetate production dropped at higher salinity likely due to the inhibited CO_(2)dissolution and acetogenic metabolism.Acetobacterium up to 78%was enriched on cathodes as the main acetogen at 35 g L^(-1).Under high-salinity selection,96.5%Acetobacterium dominated on the cathode along with 34.0%Sphaerochaeta in catholyte.This research provides a first proof of concept that MES starting from CO_(2)reduction can be achieved at elevated salinity.

关 键 词：Carbon capture and utilization High salinity Carbonate precipitates ACETOGENESIS Marine bacteria 

分 类 号：X701[环境科学与工程—环境工程]