CATALYST-INDUCED YIELD ENHANCEMENT IN A TUBULAR REACTOR

A macroreticular cation-exchange resin with an acid capacity of 5.5 me quiv/g and a higher acid group density was evaluated for MTBE formatio n from isobutylene and methanol using a 10-ft-long nonisothermal tubul ar reactor system with the methanol/isobutylene feed at close to stoic hiometric ratio. A side-by-side comparison to a standard sulfonated ca talyst (4.7 mequiv/g) shows this catalyst has a higher activity and in creases maximum conversion by 2-5% and liquid hourly space yields by 1 0-25%. Selectivities for both catalysts were close to 1. Concentration -based equilibrium constants (K(x)) for the enhanced catalyst were 870 -2500 at temperatures ranging from 343 to 313 K compared to 300-850 fo r the standard sulfonated catalyst over the same temperature range. Th e catalyst with the higher acid group density enhances the maximum con version of MTBE and increases the rate of reaction relative to the sul fonated catalyst currently in wide use in the industry.