Hydrogen Production From Agropyron Repens by Dark Fermentation With a Consolidated Bioprocessing Approach

Abstract

Agropyron repens (AR) is an invasive weed that spreads quickly and naturally in large quantities over vast areas of agricultural land. Nonetheless, the nitrogen- and carbohydrate-rich leaves and rhizomes of AR can be assessed as a possible renewable substrate for consolidated dark fermentative hydrogen production. A Box-Wilson statistical experiment design was employed to ascertain the combination of AR-rhizome and leaf concentrations that would produce the most practical hydrogen formation. Combining 14.875 g/L leaves with 125 g/L rhizomes resulted in 719.57 mL H2/100 mL and 0.22 gTVFA/gTOCo of hydrogen and total volatile fatty acid yield, respectively. For that condition, the hydrogen formation rate was 15.79 mL H2/h. Rhizome did have a more significant effect than leaf concentration on hydrogen production performance. The compost inoculum was effective for the consolidated process. Hydrogen was produced without chemical nutrient input and thermo-chemical pre-treatment of AR.