Effect of fulvic acid on hydrogen production from lignite

Lignite is not suitable as fuel due to its high moisture and ash content and low combustion efficiency. However, the high organic matter content of lignite makes it a potential raw material for microbial decomposition and hydrogen production. Hydrogen production has always been a technical challenge faced worldwide. This study used lignite as the reaction raw material to investigate the influencing factors of microbial hydrogen production, with a focus on the effect of fulvic acid, the main chemical component in lignite, on the microbial conversion of lignite for hydrogen production. By measuring the daily hydrogen production, total hydrogen production, and the content changes of humic acid and pyruvic acid in the reaction system of hydrogen produced by microorganisms in lignite, combined with spectral characteristic analysis, the mechanism of fulvic acid in hydrogen production from lignite was revealed. The research results show that the addition of fulvic acid can significantly improve the hydrogen production efficiency of lignite, especially when the addition amount is 100 mg/L, the promoting effect is the most obvious. The total hydrogen production reached 2.140 mL/g, which was 1.44 times that of the control group.