Comparison of Pretreatment Methods for the Enhancement of Fermentable Sugar Production From Kitchen Waste

The effect of different chemicals (H2SO4, NaOH and H2O2) pretreatments at various concentrations and microwaveassisted chemical (NaOH, H2SO4 + NaOH and H2SO4 + NaOH + H2O2) pretreatments on conversion of lignocelluloses in kitchen waste for maximum glucose yield were comparatively investigated. Overall, pretreatment by dilute H2SO4 (2%) achieved the highest glucose yield of 39.43 g/L with glucose recovery of 98.86%. Alkali pretreatment using NaOH at different concentration shows no significant effect on the glucose generation (0.61-1.13 g/L) when NaOH concentration was increased. However, the combination of alkali pretreatment with microwave treatment resulted in a drastic increase of glucose yield in kitchen waste sample. Meanwhile, H2O2 pretreatment seems to have little effect on the glucose yield (1.53-3.05 /L) when the concentration of H2O2 was increased. But when this oxidizing agent was added to H2SO4 and NaOH -microwave treatment, it increases the glucose yield from 10.36 to 13.31 g/L. With respect to glucose recovery, all microwave-assisted chemical pretreatment achieved the value of more than 90% glucose recovery.