Enhanced Biohydrogen Production Influenced by Magnetic Nanoparticles Supplementation Using Enterobacter cloacae

Abstract

The effects of synthesized magnetic nanoparticles (0–50 mg/L) on biohydrogen production from cotton stalk hydrolysate using Enterobacter cloacae were investigated, to find out the enhancement of the bacterial hydrogen production efficiency. The magnetic Fe3O4NPs with uniform size approximately 50 nm were well synthesized and applied in the fermentative hydrogen production system, accordingly, the addition of optimum concentration of 40 mg/L Fe3O4NPs resulted in the maximum daily hydrogen production, cumulative hydrogen production, glucose utilization, xylose utilization and hydrogen yield of 462.0 ± 9.6 mL, 1625.2 ± 18.0 mL/L, 84.29 ± 0.34%, 92.36 ± 0.16%, 0.37 ± 0.004 mol H2/mol sugar separately. Moreover, the dynamically fitted parameters of hydrogen production potential (P) and hydrogen production rate (Rm) increased to 1851.92 mL/L and 20.27 mL/(L h) respectively, and the lag phase time shortened to 1.30 h also following the addition of 40 mg/L Fe3O4NPs as compared with the control treatment (0 mg/L). These results indicated the positive effects of Fe3O4NPs supplementation on fermentative hydrogen production from cotton stalk hydrolysate by E. cloacae, revealing the feasibility of applying Fe3O4NPs supplementation for enhancement of such hydrogen production system.