In relation to reaction rates occurring within catalytic reactors, explain: (a) What is meant by the term effectiveness factor? [2 marks] (b) What is meant by the term Thiele Modulus? [2 marks] (c) What is the relationship between the effectiveness factor and the generalised Thiele Modulus? Sketch a diagram indicating how the two parameters vary with each other. [6 marks] (d) A granular catalyst of irregular shape is to be used for a chemical reaction that can be assumed as first order. The concentration of the limiting reactant species is 0.028 kgmoles per cubic metre in the bulk gas phase. Measurements for the rate of chemical reaction were conducted in a spinning basket, such that the external mass transfer limitation of the reactant gas to the catalyst surface is negligible, and were calculated on the basis of reaction rate per unit volume of catalyst particles as: RAv=0.126kgmole(m3catalyst)1s1 Further measurements indicated that: the effective diffusivity of the limiting reagent was De=6.2108m2s1 the mean catalyst particle volume was Vp=1.161010m3g1 the surface area of the catalyst was Sx=3.5107m2g1 Hence determine; i. The reaction rate constant for the first order reaction. [7 marks] ii. The solid phase mass transfer limitation effectiveness factor. [3 marks] iii. Verify any assumptions made. [2 marks] iv. Do you consider that the particles are suitably sized for this chemical reaction taking place in a packed bed tubular reactor? In relation to reaction rates occurring within catalytic reactors, explain: (a) What is meant by the term effectiveness factor? [2 marks] (b) What is meant by the term Thiele Modulus? [2 marks] (c) What is the relationship between the effectiveness factor and the generalised Thiele Modulus? Sketch a diagram indicating how the two parameters vary with each other. [6 marks] (d) A granular catalyst of irregular shape is to be used for a chemical reaction that can be assumed as first order. The concentration of the limiting reactant species is 0.028 kgmoles per cubic metre in the bulk gas phase. Measurements for the rate of chemical reaction were conducted in a spinning basket, such that the external mass transfer limitation of the reactant gas to the catalyst surface is negligible, and were calculated on the basis of reaction rate per unit volume of catalyst particles as: RAv=0.126kgmole(m3catalyst)1s1 Further measurements indicated that: the effective diffusivity of the limiting reagent was De=6.2108m2s1 the mean catalyst particle volume was Vp=1.161010m3g1 the surface area of the catalyst was Sx=3.5107m2g1 Hence determine; i. The reaction rate constant for the first order reaction. [7 marks] ii. The solid phase mass transfer limitation effectiveness factor. [3 marks] iii. Verify any assumptions made. [2 marks] iv. Do you consider that the particles are suitably sized for this chemical reaction taking place in a packed bed tubular reactor