The dehydration of butanol is carried out over a silica-alumina catalyst at 680 K.
CH3CH2CH2CH2OH→catCH3CH=CHCH3+H2O
The rate law is −rBu′=kPBu(1+KBuPBu)2
with k = 0.054 mol/gcat•h•atm and K_Bu = 0.32 atm^–1. Pure butanol enters a thin-tubed, packed-bed reactor at a molar flow rate of 50 kmol/hr and a pressure of 10 atm (1013•kPa).
a. What PBR catalyst weight is necessary to achieve 80% conversion in the absence of pressure drop? Plot and analyze X, p, f (i.e., (υ/υ₀)) and reaction rate, −rA′, as a function of catalyst weight.
b. What “fluidized CSTR” catalyst weight is necessary to achieve 80% conversion?
c. Repeat (a) when there is pressure drop, with the pressure-drop parameter α = 0.0006 kg^–1. Do you observe a maximum in the rate of reaction, and if so, why? What catalyst weight is necessary to achieve 70% conversion? Compare this weight with that for no pressure drop to achieve the same conversion.