[15 marks overall] A catalyst, which consists of spherical particles of 50m diameter and density 1850kgm3, is to be contacted with a liquid hydrocarbon (density 880kgm3, and viscosity 2.75103Pas) in a fluidized bed reactor. The bed height at minimum fluidization is 1.37m and the porosity at minimum fluidization is 0.45 . i) [5 marks] Based on the assumption of small particles, determine the minimum fluidization velocity. [ 5 marks] Calculate the pressure drop across the bed at minimum fluidization. [5 marks] When the superficial velocity in the bed exceeds the terminal settling velocity of the particles, particles will be elutriated (begin to flow out of the bed). At what velocity will elutriation begin