mass transfer

Ouestion 1: Mass transfer front a packed bed of spheres An aqueous solution at a temperature of 299.25 K flows through a column having a packed bed made up of benzoic acid spheres. The benzoic acid spheres have a diameter D, = 8 x 10 m and por porosity or voidage is 0.5. The solubility of benzoic acid in the aqueous solution at 299:25 K is its exit concentration is 3 x 10 kmol/m', the inlet concentration of the aqueous solution is 1 x 10 kmol/m' and (a) determine the convective mass transfer coefficient, ke [7 marks) (b) determine the molar flux, Na, after assuming that k' = kc [3 Marks) 2.9474 x 102 kmol/m. Data given: DAB = 1.254 x 10-9m2/s Density of the solution, p = 994 kg/m3 Viscosity of the solution, u = 1 x 10-3 Pa.s