Sustainable water desalination and electricity generation in a separator coupled stacked microbial desalination cell with buffer free electrolyte circulation.
A separator coupled circulation stacked microbial desalination cell (c-SMDC-S) was constructed to stabilize the pH imbalances in MDCs without buffer solution and achieved the stable desalination. The long-term operation of c-SMDC-S, regular stacked MDC (SMDC) and no separator coupled circulation SMDC (c-SMDC) were tested. The SMDC and c-SMDC could only stably operate for 1 week and 1 month owing to dramatic anolyte pH decrease and serious biofilm growth on the air cathode, respectively. The c-SMDC-S gained in anolyte alkalinity and operated stably for about 60 days without the thick biofilm growth on cathode. Besides, the chemical oxygen demand removal and coulombic efficiency were 64 ± 6% and 30 ± 2%, higher than that of SMDC and c-SMDC, respectively. It was concluded that the circulation of alkalinity could remove pH imbalance while the separator could expand the operation period and promote the conversion of organic matter to electricity.
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
Xi
X
Chen
Peng
P
Liang
Zhimou
Z
Wei
Xiaoyuan
X
Zhang
Xia
X
Huang
D001674:Bioelectric Energy Sources / Q000382:microbiology*; D003247:Conservation of Natural Resources / Q000379:methods*; D004573:Electrolytes / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D054712:Salinity; D012623:Seawater / Q000737:chemistry* / Q000382:microbiology*; D014871:Water Microbiology; D018508:Water Purification / Q000295:instrumentation*
D004573:Electrolytes