3. Reactant purification The CAT2 catalyst requires an undesirable impurity, S, in the feed of the packed bed reactor to be removed before entering the reactor. This is done by separating S with a membrane and then absorption of pure gaseous S in a solvent with a high concentration of reactant B (which is added to increase the rate of absorption) in an agitated reactor. 1.5 S (gl) + B(l) Q(l) (where "g" indicates gas phase and "/" indicated liquid phase). The conversion of B is kept low, so the reaction rate is approximately independent of the concentration of B and is pseudo-first order with respect to dissolved concentration of S: -rs = kBoS where the rate is given in terms of S reacting, kmols s-1 m. Assume that the reactor is well mixed for both the gas and the liquid, and there is no mass transfer resistance in the gas phase. a) Calculate the Hatta number and determine the enhancement factor. [4]