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Immobilised lactase is used to hydrolyse lactose in dairy waste to glucose and galactose. Enzyme is immobilised in resin particles and packed into a 0.5 m3 column. The total effectiveness factor for the system is close to unity; Km for the immobilised enzyme is 1.32 kg m-3; Vmax is 45 kg m-3 h-1. The lactose concentration in the feed stream is 9.5 kg m-3; a substrate conversion of 98% is required. The column is operated with plug flow for a total of 310 d per year. At what flow rate should the reactor be operated?

Immobilised lactase is used to hydrolyse lactose in dairy waste to glucose and galactose. Enzyme is immobilised in resin particles and packed into a 0.5 m3 column. The total effectiveness factor for the system is close to unity; Km for the immobilised enzyme is 1.32 kg m-3; Vmax is 45 kg m-3 h-1. The lactose concentration in the feed stream is 9.5 kg m-3; a substrate conversion of 98% is required. The column is operated with plug flow for a total of 310 d per year. At what flow rate should the reactor be operated? Correct Answer 1.56 m3 h-1

For 98% substrate conversion, sf = (0.02 sI) = 0.19 kg m-3

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Pick out the wrong statement below:
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III. Arrehenius equation describing the effect of temperature on rate constant is given by, $${\text{K}} = {\text{A}}.{{\text{e}}^{ - \frac{{{\text{Ea}}}}{{{\text{RT}}}}}}$$
IV. The mechanism for the decomposition of CH3CHO into CH4 and CO in presence of I2 is:
CH3CHO + I2 → CH3I + HI + CO; slow
CH3I + HI → CH4 + I2; fast
Then the rate of disappearance CH3CHO is equal to K.CCH3l.CHl and acts as a catalyst.