Modelling anaerobic sulfide removal by sulfide shuttling bacteria

Area of Science:

• Microbiology
• Biotechnology
• Environmental Science

Background:

• Sulfide oxidizing bacteria are crucial for industrial biodesulfurization, converting toxic sulfide to elemental sulfur.
• These bacteria function as sulfide shuttles, spatially separating sulfide oxidation from terminal electron transfer, but the underlying mechanisms remain unclear.
• Understanding these mechanisms is vital for optimizing industrial biodesulfurization processes.

Purpose of the Study:

• To develop and validate a novel model for anaerobic sulfide removal.
• To elucidate the mechanisms of sulfide shuttling in sulfide oxidizing bacteria.
• To improve the accuracy of models used in industrial biodesulfurization systems.

Main Methods:

• Development of a new mathematical model for anaerobic sulfide removal using newly obtained sulfide removal data.
• Comparison of the new model's performance against two previously published models.
• Incorporation of pH effects and sulfide concentration dependencies into the model.

Main Results:

• The newly developed two-stage model, comprising a fast chemical step and a slow enzymatic step, significantly improved predictions of anaerobic sulfide removal compared to existing models.
• The model accurately reflects higher total sulfide removal at increasing pH.
• The model also accounts for partial sulfide removal observed at higher sulfide concentrations.

Conclusions:

• The proposed two-stage model provides a more accurate representation of anaerobic sulfide removal mechanisms.
• The model's inclusion of pH and sulfide concentration effects enhances its applicability to industrial biodesulfurization.
• This work represents a significant step towards precise modeling of anaerobic sulfide removal in industrial settings.