title: Bio-electrolytic conversion of acidogenic effluents to biohydrogen: an integration strategy for higher substrate conversion and product recovery.
abstract: Feasibility of integrating Microbial electrolysis cell (MEC) process with dark-fermentation process for additional hydrogen recovery as well as substrate degradation was demonstrated in the present study. MEC was employed in order to utilize the residual organic fraction present in the acidogenic effluents of dark fermentation process as substrate for hydrogen production with input of small electric current. MEC was operated at volatile fatty acids (VFA) concentration of 3000 mg/l under different poised potentials (0.2, 0.5, 0.6, 0.8 and 1.0 V) using anaerobic consortia as biocatalyst. Maximum hydrogen production rate (HPR), cumulative hydrogen production (CHP) (0.53 mmol/h and 3.6 mmol), dehydrogenase activity (1.65 μg/ml) and VFA utilization (49.8%) was recorded at 0.6 V. Bio-electrochemical behavior of mixed consortia was evaluated using cyclic voltammetry and by Tafel slope analysis. Microbial diversity analysis using denaturing gradient gel electrophoresis confirmed the presence of γ-proteobacteria (50%), Bacilli (25%) and Clostridia (25%).
authors: Bioengineering and Environmental Centre (BEEC), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad, India.
authors: M Lenin
authors: ML
authors: Babu
authors: G Venkata
authors: GV
authors: Subhash
authors: P N
authors: PN
authors: Sarma
authors: S Venkata
authors: SV
authors: Mohan
mesh_terms: D000143:Acids / Q000378:metabolism*; D001419:Bacteria / Q000201:enzymology / Q000235:genetics; D001483:Base Sequence; D001673:Biodegradation, Environmental; D056804:Biofuels / Q000382:microbiology*; D004275:DNA, Ribosomal / Q000235:genetics; D058645:Denaturing Gradient Gel Electrophoresis; D055664:Electrochemical Techniques; D004572:Electrolysis / Q000379:methods*; D005232:Fatty Acids, Volatile / Q000032:analysis; D006859:Hydrogen; D006863:Hydrogen-Ion Concentration; D010088:Oxidoreductases / Q000378:metabolism; D010802:Phylogeny; D062065:Wastewater / Q000382:microbiology*; D018508:Water Purification / Q000379:methods*
chemical_list: D000143:Acids; D056804:Biofuels; D004275:DNA, Ribosomal; D005232:Fatty Acids, Volatile; D006859:Hydrogen; D010088:Oxidoreductases; D062065:Wastewater