Assessment of local biochar varieties as strategic modulators in enhancing biohydrogen yields via dark fermentation

İngilizce (OpenAlex)

Growing pressures on fossil resources and climate targets motivate efficient biohydrogen routes. This study systematically assessed how locally sourced biochars—wood waste, almond shell, pine and olive pits—and their dosages modulate dark-fermentative H2 production. Ten-day batch assays at 37 °C tested three biochar loadings (0.5, 1.0 and 1.5 g per bottle), tracking cumulative H2, production rate, volatile fatty acids (VFAs) and fermentation performance. Results showed that all biochars enhanced hydrogen production relative to the control, with wood waste (up to 142.5 mL H2 at 0.5 g) and olive pit (134.7 mL H2 at 1.5 g) biochars showing superior performance due to their favorable physicochemical properties. These included high carbon content, moderate O/C and H/C atomic ratios, and relatively high BET surface areas, as confirmed by ultimate/proximate and BET analyses. Volumetric hydrogen yields were also significantly improved with pine biochar (35.3%) and almond shell biochar (31.4%) compared to the control (30.2%). These results position low-cost regional biochars as strategic modulators to boost H2 productivity and steer VFA profiles, supporting waste valorization and clean energy generation.