#Question id: 14400
#Section 5: Bioprocess Engineering and Process Biotechnology
internal mass transfer effects are eliminated when the internal effective ness factor is
#Question id: 14401
#Section 5: Bioprocess Engineering and Process Biotechnology
Denitrifying bacteria are immobilised in gel beads and
used in a stirred reactor for removal of nitrate from groundwater. At a nitrate
concentration of 3 g m -3, the conversion rate is 0.011 g s-1 m-3
catalyst. The effective diffusivity of nitrate in the gel is 1.5 × 10 -9
m 2 s-1, the beads are 6 mm in diameter, and the
liquid-solid mass-transfer coefficient is 10 -5 m s-1. Km
for the immobilised bacteria is approximately 25 g m -3. Calculate
the observable Thiele modulus with CAs = 1.9 g m -3
#Question id: 14402
#Section 5: Bioprocess Engineering and Process Biotechnology
#Question id: 14403
#Section 5: Bioprocess Engineering and Process Biotechnology
Invertase is immobilised in ion-exchange resin of average diameter 1 mm. The amount of enzyme in the beads is measured by protein assay as 0.05 kg m ^-3. 20 cm ^3 beads are packed into a small column reactor; 75 ml sucrose solution at a concentration of 16 mM is pumped rapidly through the bed. In another reactor an identical quantity of free enzyme is mixed into the same volume of sucrose solution. Assume the kinetic parameters for free and immobilised enzyme are equal: K,,, is 8.8 mM and the turnover number is 2.4 x 10 gmol glucose (g enzyme)-'s^-1. The effective diffusivity of sucrose in the ion-exchange resin is 2 x 10^-6cm2s 4. What is the rate of reaction by free enzyme?
#Question id: 14404
#Section 5: Bioprocess Engineering and Process Biotechnology
#Question id: 14405
#Section 5: Bioprocess Engineering and Process Biotechnology