Mitigating thiols-induced inhibition in biological desulfurization: Selecting thiols-tolerant sulfur-oxidizing bacteria under haloalkaline conditions

[Display omitted] •Sulfur-oxidizing bacteria from Landfill C solutions were successfully identified.•Certain SOBs had superior desulfurization capacities under haloalkaline conditions.•T. versutus D301′s capacity were inhibited by thiols in 80% Landfill C solutions.•Other desulfurizing bacteria in Landfill C solutions mitigated thiols’ inhibition. Biological desulfurization (BDS) represents a sustainable technology for eliminating hydrogen sulfide from energy gases via sulfur-oxidizing bacteria (SOB). However, the presence of thiols within gas streams presents a significant challenge, inhibiting the activity of SOB and the formation of bio-sulfur particles (BSNPs), thereby reducing the efficiency and stability of the BDS process. This study sought to address this issue by selecting thiols-tolerant SOBs from Landfill C and evaluating their desulfurization performance under haloalkaline and alkalescent conditions, including growth, bio-oxidation, BSNPs production, particle size, and surface potential. While the thiols tolerance of D301 in industrial environments was examined. The findings revealed that specific SOB strains, such as Halothiobacillus kellyi, Thioalkalibacter halophilus, and Thioalkalivibrio sp. D309, exhibited superior desulfurization performance under haloalkaline conditions. Additionally, D301's growth and desulfurization capacities were inhibited by thiols in 80% industrial Landfill C solutions, though this inhibition was alleviated in the presence of other desulfurizing bacteria. The research offers valuable insights into optimizing BDS processes in the presence of thiols and highlights the promise of haloalkaline conditions in supporting SOBs that can overcome industrial challenges, paving the way for more efficient and stable BDS applications.