(567b) Zeolite Membrane Reactor for High-Temperature Isobutane Dehydrogenation Reaction: Effects of Membrane Properties and Operating Conditions

Effects of Membrane Properties and Operating Conditions

Shailesh Dangwal, Ruochen Liu, Seok-Jhin Kim*

School of Chemical Engineering, Oklahoma State University,

420 Engineering North, Stillwater, OK 74078, USA

ABSTRACT

Isobutylene plays an instrumental role as an intermediate in many important chemical engineering processes. Its use in making gasoline oxygenates, fuel additives and butyl rubber adds up to its demand and stimulates research for new energy efficient ways for its production. Catalytic dehydrogenation of isobutane using a membrane reactor is a feasible solution not only because it helps in overcoming thermodynamic limitations by shifting the equilibrium towards isobutylene but also it substantially separates isobutylene by preferentially allowing only H₂ to permeate through the membrane. In this study, dehydrogenation of isobutane in packed-bed membrane reactors operating with a Pt/Al₂O₃ catalyst is reported. The effects of MFI zeolite membranes on isobutane conversion, isobutylene selectivity and isobutylene yield are investigated experimentally and by simulations using a simple one-dimensional model. MFI membrane reactors allow the thermodynamic equilibrium limit of isobutane conversion to be surpassed at high temperatures. The experimental results and the model calculations demonstrate that medium-pore MFI membranes with good H₂/i-C₄H₁₀ selectivity can effectively enhance isobutane conversion at high operation temperature by timely removal of H₂ through the membranes. *Corresponding author: E-mail: seokjhin.kim@okstate.edu