Effect of phenolic compounds on hydrogen production from municipal solid waste

The present study evaluates the effect of phenolic inhibitors viz. m-cresol, pentachlorophenol, bisphenol-A, and catechol on hydrogen production from anaerobic digestion of organic fraction of the municipal solid waste. Various concentration range of phenolic compounds (0.5, 2.5, 5.0, 10 and 25 mg/L) was applied. The results revealed that the inhibition coefficient of pentachlorophenol was highest among all the inhibitors resulting in lowest hydrogen production and yield. In control, the cumulative hydrogen production was 227.9 ± 10.5 mL which declined to a minimum of 93.4 ± 10.1 mL, 36.4 ± 10.1 mL, 58.9 ± 10.4 mL and 85.8 ± 10.3 mL for experimental batches supplemented with m-cresol, pentachlorophenol, bisphenol-A and catechol respectively. The corresponding decline in the hydrogen yield was 28.0%, 43.8%, 37.1% and 31.8% respectively. Further analysis revealed that inhibitors were completely removed up to a concentration not exceeding 0.25 mg/L. However, at higher concentrations, inhibitors removal efficiency was declined. COD removal efficiency was also negatively affected by inhibitors.