Hydrogen Production from Starch Wastewater Using Anaerobic Sludge Immobilized on Maghemite Nanoparticle

In this study, hydrogen production from starch wastewater using anaerobic sludge immobilized on maghemite nanoparticles (γ-Fe2O3) was investigated. Two anaerobic baffled reactors (ABR-1 and ABR-2) were operated at organic loading rate (OLR) of 3.63±0.43 g-COD/L.d and hydraulic retention time (HRT) of 10 h. The ABR-1 was inoculated with 3.5 g-VSS/L preheated sludge at 90°C for 30 minutes. The seeded sludge, in ABR-2, was immobilized on maghemite nanoparticles with a ratio of 25 mg-(γ-Fe2O3)/g-VSS. The maghemite nanoparticles were observed by scanning electron microscopy (SEM). Results obtained indicated that, chemical oxygen demand (COD) removal efficiency and hydrogen production rate were higher in ABR-2 as compared to ABR-1. COD removal efficiency of ABR-1 and ABR-2 were 46.6±8 and 63.4±4.9%, respectively. Moreover, 7±1 and 12±1.7% of the total influent COD, for ABR-1 and ABR-2 respectively, were converted to hydrogen gas. Based on these results, adding maghemite nanoparticle to the inoculated sludge would enhance the fermentation process and produce higher effluent quality.