The sulfur compounds present in petroleum fractions such as diesel can be removed by contact with a porous catalyst containing active metals such as Mo in the presence of hydrogen

The sulfur compounds present in petroleum fractions such as diesel can be removed by contact with a porous catalyst containing active metals such as Mo in the presence of hydrogen. If the catalyst is 3 mm in radius and the concentration of sulfur in the liquid surrounding the catalyst is 10 mol/m3 find the rate of reaction. Assume that the reaction is of second order in sulfur concentration with a volumetric rate constant of 5 m3/mol·s. Note that these numbers are arbitrary and for illustration purposes only. Use De = 1 × 10−9 m2/s.