The anaerobic oxidation of dissolved H
2S into elemental sulfur was studied at 23°C and pH 6.5±0.3 in a continuous culture of the phototrophic green sulfur bacterium
Chlorobium limicola. The number of free cells formed in the culture was proportional to the amounts of H
2S oxidized, and the growth yield was independent of light intensity. The specific growth rate was significantly dependent on the dissolved H
2S concentration (0.03-3.16mol·m
-3) and light intensity (200-16000 1x), and the kinetic data were analyzed with a rate expressed as a function of each rate-limiting factor. Under illumination by white fluorescent lamps, the specific oxidation rate of
C. limicola reached a maximum of 2.08×10
-14 molh
-1·cell
-1 when the dissolved H
2S concentration was 2.29 mol·m
-3 at 5000 lx. The phototrophic H
2S oxidation rates per unit reactor volume were quantitatively simulated as a function of the number of equal-size reactors placed in series, by using the rate expression and estimated growth parameter values.
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