Unlocking methanogenesis at 45°C: Synergistic roles of Zero-Valent iron and magnetite in Restoring cellulose anaerobic digestion
Year: 2025
Type: article
Abstract: Anaerobic digestion (AD) operated at transitional temperature is a promising technology for treating de-oiled food waste (FW). However, under such conditions, the metabolic activity of methanogens will be significantly negatively affected compared to conventional mesophilic or thermophilic conditions, which limits its practical application. In this study, the AD of cellulose at 45 °C were investigated, and the synergistic effects of zero-valent iron (ZVI) and magnetite (Fe 3 O 4 ) on enhancing methanogenesis were explored. The results indicated that the combination of ZVI and Fe 3 O 4 played a crucial role in promoting cellulose methanogenesis during AD at 45 °C. Specifically, the methane yield reached 300.1 mL/g VS, representing a 58 % increase compared to the control group. Further analysis revealed that ZVI + Fe 3 O 4 enhanced the levels of coenzyme F420 and acetate kinase. Firmicutes and Methanosarcina were the dominant microbial groups involved in normal methanogenesis at 45 °C, and a positive correlation between these two groups was observed. Metagenomic sequencing further demonstrated that the combination of ZVI and Fe 3 O 4 synergistically increased the abundance of genes associated with both acetate cleavage and CO 2 reduction methanogenic pathways. The dominant pathways achieved a dynamic equilibrium, functioning according to the available substrates at different stages within the reactor. Life Cycle Assessment (LCA) results indicated that coupling ZVI and Fe 3 O 4 could effectively reduce carbon emissions and fossil resource depletion. The study provided theoretical evidence for the application of AD in treating cellulose-based substrates at transitional temperatures.
Source: Waste Management
Authors: Yuxin Chen, Xin Kong, Xumiao Mao, Xiaojun Fan, Jin Yuan
Institution: Taiyuan University of Technology
Language: English
Subfield: Building and Construction
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,450
OpenAlex ID: W4415880113