Bubble coalescence suppression driven carbon monoxide (CO)-water mass transfer increase by electrolyte addition in a hollow fiber membrane bioreactor (HFMBR) for microbial CO conversion to ethanol. (September 2018)

• Record Type: Journal Article
• Authors: Jang, Nulee; Yasin, Muhammad; Kang, Hyunsoo; Lee, Yeubin; Park, Gwon Woo; Park, Shinyoung; Chang, In Seop
• Is Part Of: Bioresource technology. Volume 263(2018)
• Page Start: 375
• Page End: 384
• Publication Date: 2018-09
• Subjects: Gas–liquid mass transfer -- Bubble coalescence -- Syngas fermentation -- Carbon monoxide -- Bioethanol; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2018.05.012
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Microbubble generation using electrolytes in HFMBR without mechanical mixing. Change in mass transfer rate depends on electrolyte type and concentration. First application of electrolyte-based mass transfer system to syngas fermentation. Microbial growth and ethanol production can be supported by electrolyte-based HFMBR. Abstract: This study investigated the effects of electrolytes (CaCl2, K2 HPO4, MgSO4, NaCl, and NH4 Cl) on CO mass transfer and ethanol production in a HFMBR. The hollow fiber membranes (HFM) were found to generate tiny gas bubbles; the bubble coalescence was significantly suppressed in electrolyte solution. The volumetric gas-liquid mass transfer coefficients ( k L a ) increased up to 414% compared to the control. Saturated CO ( C ∗ ) decreased as electrolyte concentrations increased. Overall, the maximum mass transfer rate ( R max ) in electrolyte solution ranged from 106% to 339% of the value obtained in water. The electrolyte toxicity on cell growth was tested using Clostridium autoethanogenum . Most electrolytes, except for MgSO4, inhibited cell growth. The HFMBR operation using a medium containing 1% MgSO4 achieved 119% ethanol production compared to that without electrolytes. Finally, a kinetic simulation using the parameters got from the 1% MgSO4 medium predicted a higher ethanol production compared to the control.