TY - JOUR
T1 - Microbial Electrolytic Carbon Capture for Carbon Negative and Energy Positive Wastewater Treatment
AU - Lu, Lu
AU - Huang, Zhe
AU - Rau, Greg H.
AU - Ren, Zhiyong Jason
PY - 2015/7/7
Y1 - 2015/7/7
N2 - Energy and carbon neutral wastewater management is a major goal for environmental sustainability, but current progress has only reduced emission rather than using wastewater for active CO2 capture and utilization. We present here a new microbial electrolytic carbon capture (MECC) approach to potentially transform wastewater treatment to a carbon negative and energy positive process. Wastewater was used as an electrolyte for microbially assisted electrolytic production of H2 and OH- at the cathode and protons at the anode. The acidity dissolved silicate and liberated metal ions that balanced OH-, producing metal hydroxide, which transformed CO2 in situ into (bi)carbonate. Results using both artificial and industrial wastewater show 80-93% of the CO2 was recovered from both CO2 derived from organic oxidation and additional CO2 injected into the headspace, making the process carbon-negative. High rates and yields of H2 were produced with 91-95% recovery efficiency, resulting in a net energy gain of 57-62 kJ/mol-CO2 captured. The pH remained stable without buffer addition and no toxic chlorine-containing compounds were detected. The produced (bi)carbonate alkalinity is valuable for wastewater treatment and long-term carbon storage in the ocean. Preliminary evaluation shows promising economic and environmental benefits for different industries. (Figure Presented).
AB - Energy and carbon neutral wastewater management is a major goal for environmental sustainability, but current progress has only reduced emission rather than using wastewater for active CO2 capture and utilization. We present here a new microbial electrolytic carbon capture (MECC) approach to potentially transform wastewater treatment to a carbon negative and energy positive process. Wastewater was used as an electrolyte for microbially assisted electrolytic production of H2 and OH- at the cathode and protons at the anode. The acidity dissolved silicate and liberated metal ions that balanced OH-, producing metal hydroxide, which transformed CO2 in situ into (bi)carbonate. Results using both artificial and industrial wastewater show 80-93% of the CO2 was recovered from both CO2 derived from organic oxidation and additional CO2 injected into the headspace, making the process carbon-negative. High rates and yields of H2 were produced with 91-95% recovery efficiency, resulting in a net energy gain of 57-62 kJ/mol-CO2 captured. The pH remained stable without buffer addition and no toxic chlorine-containing compounds were detected. The produced (bi)carbonate alkalinity is valuable for wastewater treatment and long-term carbon storage in the ocean. Preliminary evaluation shows promising economic and environmental benefits for different industries. (Figure Presented).
UR - http://www.scopus.com/inward/record.url?scp=84936804089&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84936804089&partnerID=8YFLogxK
U2 - 10.1021/acs.est.5b00875
DO - 10.1021/acs.est.5b00875
M3 - Article
C2 - 26076212
AN - SCOPUS:84936804089
VL - 49
SP - 8193
EP - 8201
JO - Environmental Science & Technology
JF - Environmental Science & Technology
SN - 0013-936X
IS - 13
ER -