Kinetics of hydrogen sulfide oxidation by immobilized autotrophic and heterotrophic bacteria in bioreactors

The kinetics of H2S oxidation in bioreactors with separately packed autotrophic Thiobacillus thioparus CH11 and heterotrophic Pseudomonas putida CH11 were evaluated. The reaction rates were determined to be first-order below 20 ppm, zero-order above 60 ppm, and fractional-order in the intermediate concentration ranges for the Thiobacillus thioparus CH11 bioreactor, the first-order below 35 ppm, zero-order above 80 ppm, and fractional-order in the intermediate concentration ranges for the Pseudomonas putida CH11 bioreactor. The saturation constants for H2S by Thiobacillus thioparus CH11 and Pseudomonas putida CH11 were calculated to be 30.3 ppm and 44.2 ppm, respectively.