An Evaluation of Kinetic Models in the Biodesulfurization of Synthetic Oil by Rhodococcus erythropolis ATCC 4277

Biodesulfurization is an eco-friendly technology applied in the removal of sulfur from fossil fuels. This technology is based on the use of microorganisms as biocatalysts to convert the recalcitrant sulfur compounds into others easily treatable, as sulfides. Despite it has been studied during the last decades, there are some unsolved questions, as per example the kinetic model which appropriately describes the biodesulfurization globally. In this work, different kinetic models were tested to a batch desulfurization process using dibenzothiophene (DBT) as a model compound, n-dodecane as organic solvent, and Rhodococcus erythropolis ATCC 4277 as biocatalyst. The models were solved by ODE45 function in the MATLAB. Monod model was capable to describe the biodesulfurization process predicting all experimental data with a very good fitting. The coefficients of determination achieved to organic phase concentrations of 20, 80, and 100 % (v/v) were 0.988, 0.995, and 0.990, respectively. R. erythropolis ATCC 4277 presented a good affinity with the substrate (DBT) since the coefficients of saturation obtained to reaction medium containing 20, 80, and 100 % (v/v) were 0.034, 0.07, and 0.116, respectively. This kinetic evaluation provides an improvement in the development of biodesulfurization technology because it showed that a simple model is capable to describe the throughout process.