Question

1. The decomposition of cyclohexane to benzene and hydrogen is mass transfer-limited at high temperature. The reaction is carried out in a 5-cm-ID pipe 20 m in length packed with

cylindrical pellets 0.5 cm in diameter and 0.5 cm in length. The pellets are coated with the catalyst only on the outside. The bed porosity is 40%. The entering volumetric flow rate is 60 dm/min. 1.1. Calculate the number of pipes necessary to achieve 99.9% conversion of cyclohexane from an entering gas stream of 1% cyclohexane and 99% H2 at 2 atm and 500°C. 1.2. Plot conversion as a function of length. 1.3. How much would your answer change if the pellet diameter and length were each cut in half?

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