(515g) Modeling and Simulation of a Combined Reactor/Pressure Swing Adsorption Unit for Isomerization of a Mixed Feed of Pentanes and Hexanes

In this work, a novel process for isomerizing and separating n-pentane and n-hexane to their branched isomers is proposed. Both reactor and separation units are combined in one vessel. The vessel is divided into two sections: a reactor section and a PSA separation section. The reactor section is packed with Pt/Y-zeolite catalyst. The PSA separation section is equipped with a 5A zeolite adsorbent. A dispersed plug flow mathematical model of the entire process is developed. The model links both reactor and separation sections. The model is used to investigate the dynamics of the PSAR units. For a feed to a conventional PSAR unit, containing an equimolar fractions of 0.03 for each of n-C5, n-C6, i-C5 and i-C6, the molar fractions of i-C5 and i- C6 rise to values of 0.0439 and 0.045 after reaching equilibrium conversion at the end of the reactor section. The PSA section allows for complete separation of n-C5 and n-C6 from the reactor section effluent stream. In this paper we report the use of a hydrogen purge only. However, recycling of waste streams back to the process allows for recovery of valuable hydrocarbon material.