Study on the effects and mechanisms of different coal matrix structures on the desulfurization efficiency of Pseudomonas putida

This study aims to reveal the influence mechanism of coal matrix structure on microbial desulfurization efficiency and clarify the regulatory effect of coal chemical structural characteristics on microbial desulfurization efficiency, providing theoretical support for the precise application of coal biodesulfurization technology. Pseudomonas putida was used as the functional strain for microbial desulfurization experiments on 092a and 100b coal samples with significant structural differences, and the characteristics of the desulfurized coal samples were characterized by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The results showed that the organic sulfur removal rate of 100b coal reached 60.9%, which was much higher than the 17.6% of 092a coal; Pseudomonas putida could efficiently degrade various forms of organic sulfur such as thiophene, sulfide and sulfoxide in 100b coal, while only selectively removing sulfone-type sulfur in 092a coal, and FTIR characterization further confirmed that coal matrix characteristics are the core factor determining the desulfurization efficiency of this strain. The high aromaticity and high condensation degree of 092a coal resulted in significant steric hindrance of sulfur components, which limited the specific binding between enzymes and substrates, whereas the thiophene sulfur in 100b coal could be efficiently degraded through the 4S metabolic pathway, and this study clarifies the regulatory effect of coal chemical structural characteristics on microbial desulfurization efficiency, further supplementing the theoretical basis for the precise application of coal biodesulfurization technology.