Enhanced production of biohydrogen and biomethane through a two-stage anaerobic fermentation of food waste mixed with conductive additives

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2023-11, Vol.476, p.146520, Article 146520
• Main Authors: Kim, Tae-Hoon, Song, Dayeong, Jeon, Yun-Ju, Hwang, Okhwa, Nam, Joo-Youn, Yun, Yeo-Myeong
• Format: Article
• Language: English
• Subjects: Conductive material; Food waste; Hydrogen; Methane; Two-stage fermentation process
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2023.146520

[Display omitted] •This work revealed unique roles of different CMs in TSFP for H2 and CH4 production.•Combining multiple CMs significantly increased H2 and CH4 production in TSFP.•MNP had the most favorable performance for enhanced H2 production.•PAC made the greatest contribution to improving CH4 production and COD removal. This study was conducted to examine the effects of three different conductive materials (CMs) on H2 and CH4 production in a two-stage fermentation process (TSFP). This study also investigated the distinct roles played by the different types of CMs within the process. The study findings revealed that the combination of two or more CMs led to a significant improvement in production compared to using a single CM. Magnetite nanoparticle (MNP) played a crucial role in enhancing H2 productivity during the first stage of the TSFP. The TSFP with carbon nanotubes (CNT) + MNP demonstrated the highest H2 yield of 121 ± 7 mL/g·COD with the H2 production rate of 219 ± 18 mL/hr, followed by the TSFP with MNP alone yielded the second highest H2 of 81 ± 5 mL/g·COD with the H2 production rate of 169 ± 25 mL/hr. Both powdered activated carbon (PAC) alone (277 ± 17 mL/g·COD) and PAC + CNT (278 ± 15 mL/g·COD) showed the highest CH4 yield, indicating that PAC contributed to higher CH4 production in the second stage of the TSFP. The addition of PAC to the samples led to higher chemical oxygen demand (COD) removal efficiency in the TSFP, while the presence of MNP significantly increased the total energy production.