Effect of surfactants on the formation and metabolism of sulfur particles by Thialkalivibrio versutus D301

Abstract:

[Background] Bio-desulfurization is an effective method of removing hydrogen sulfide from industrial gas, biogas, natural gas, etc. In the process of bio-desulfurization, the formation and metabolism of sulfur particles is the key steps that directly affect the efficiency of desulfurization. However, our understanding of the methods of regulating sulfur particles is still insufficient. [Objective] The effects of different surfactants on the formation and metabolism of sulfur particles by Thialkalivibrio versutus D301 were studied. [Methods] T. versutus D301 was cultured in erlenmeyer flask, and the sulfur-oxidizing bacterica and sulfur particles were characterized by X-ray diffraction (XRD), cold field emission scanning electron microscopy (SEM), energy dispersive system (EDS) and Fourier transform infrared spectroscopy (FTIR). [Results] The elemental sulfur in sulfur particle mainly exists in the form of S8. The addition of Tween-80 or SDS has a significantly effect on the morphology and production of sulfur particles. In the control experiment, the sulfur particles generated were regular spherical, smooth and intact, and biological macromolecules such as proteins cover to the surface of the sulfur particles. When 0.01 g/L Tween-80 is added, long rod-shaped and larger-sized sulfur particles are formed and the metabolic rate of elemental sulfur slows down. When 0.3 g/L SDS is added, the sulfur particles are in the form of short rods. Less sulfur particles are formed, and they are rapidly metabolized by T. versutus D301. [Conclusion] Regulating the morphology and metabolic rate of sulfur particles can be achieved by adding specific surfactants during bacterial cultivation.