title: Enhancement of acetate productivity in a thermophilic (55 °C) hollow-fiber membrane biofilm reactor with mixed culture syngas (H2/CO2) fermentation.
abstract: Conversion of organic wastes to syngas is an attractive way to utilize wastes. The produced syngas can be further used to produce a variety of chemicals. In this study, a hollow-fiber membrane biofilm reactor with mix cultures was operated at 55 °C to convert syngas (H2/CO2) into acetate. A high concentration of acetate (42.4 g/L) was reached in batch experiment while a maximum acetate production rate of 10.5 g/L/day was achieved in the continuous-flow mode at hydraulic retention time (HRT) of 1 day. Acetate was the main product in both batch and continuous-flow experiments. n-Butyrate was the other byproduct in the reactor. Acetate accounted for more than 98.5 and 99.1% of total volatile fatty acids in batch and continuous modes, respectively. Illumina Miseq high-throughput sequencing results showed that microorganisms were highly purified and enriched in the reactor. The main genus was Thermoanaerobacterium (66% of relative abundance), which was usually considered as H2producer in the literature, however, likely played a role as a H2consumer in this study. This study provides a new method to generate the high producing rate and purity of acetate from syngas.
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, People's Republic of China.
authors.forename: Yun-Qi
authors.initials: YQ
authors.lastname: Wang
authors.affiliation: School of Resources and Environment, Anqing Normal University, Anqing, Anhui, China.
authors.forename: Shi-Jin
authors.initials: SJ
authors.lastname: Yu
authors.affiliation: Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, People's Republic of China.
authors.forename: Fang
authors.initials: F
authors.lastname: Zhang
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, People's Republic of China.
authors.forename: Xiu-Yang
authors.initials: XY
authors.lastname: Xia
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, People's Republic of China. rzeng@ustc.edu.cn.
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Zeng
mesh_terms: D019342:Acetic Acid / Q000378:metabolism*; D061249:Batch Cell Culture Techniques; D018441:Biofilms / Q000254:growth & development; D019149:Bioreactors; D020148:Butyric Acid / Q000378:metabolism; D002245:Carbon Dioxide / Q000378:metabolism*; D005285:Fermentation; D059014:High-Throughput Nucleotide Sequencing; D006859:Hydrogen / Q000378:metabolism*; D059013:Microbial Consortia / Q000235:genetics*; D012722:Sewage / Q000737:chemistry / Q000382:microbiology*; D046950:Thermoanaerobacterium / Q000235:genetics* / Q000378:metabolism
chemical_list: D012722:Sewage; D020148:Butyric Acid; D002245:Carbon Dioxide; D006859:Hydrogen; D019342:Acetic Acid
keywords: High acetate production rate; High purity of acetate; Mixed culture syngas (H2/CO2) fermentation; Thermoanaerobacterium; Thermophilic hollow-fiber membrane biofilm reactor