Question 3 (30%) A slurry bubble column is used to investigate the oxidation of ethanol to ethanoic acid. C2H5OH + O2(8+1 CH,COOH + H20) During the process the gas phase can be assumed dispersed in a well-mixed liquid phase. Gas side mass transfer limitations and catalyst intra-particle resistances are negligible. The molar fraction of oxygen at the inlet of the gas stream was 5% (v/v), the molar fraction of oxygen at the outlet of the liquid stream is 1.5% (v/v), and the molar fraction of ethanol at the inlet of the liquid (solvent) stream was 4% (v/v). (b) (a) Using the Hatta number, determine the mechanism that controls the reaction. [6%] Calculate the conversion of ethanol. [16%] (c) Calculate the consumption rate of oxygen at the outlet. If the bubbles in the column have all the same size, estimate their size. [8%] Data: Operating pressure = 25 bar Concentration of A in the liquid phase = 90 molm? Molar density, P=6000mol m Molar flow rate (gas stream) = 110 mols? gas void fraction, Eg = 0.5 Volume of reactor = 2 m3 Mass transfer coefficient (liquid film), k = 5-10ms? Diffusion coefficient, D = 8-10?m? s? Henry's law: PA/CA = 600 Pa m'mol Specific interfacial area (bubble), a'v= 1100 m m reactor Oz is consumed with a reaction rate constant, k=0.025 s