Membrane reactor design guidelines for ammonia decomposition

Design guidelines were applied for an ammonia decomposition membrane reactor, and the limits of operation were determined. Maximum exit conversions using the membrane reactor were 1.5 < log(Pe) < 2 and −0.5 < log(Da) < 0. Increasing temperature had a positive effect on membrane reactor conversion. The effect of sweeping gas flow was relatively low. A design chart was created to illustrate dynamics between permeation rates and reaction rates with conversion. A mathematical model was derived to represent mass conservation in the tube and shell sides of the reactor. These guidelines can be used for the design and analysis for membrane reactor removal of ammonia after Selective Catalytic Reduction of NOx.

Design chart for ammonia decomposition in a membrane reactor. Contour of exit conversion of a membrane reactor as a function of Pe and Da.Figure optionsDownload high-quality image (137 K)Download as PowerPoint slideHighlights
► Selective Catalytic Reduction of NOx (SCR) along with membrane reactor is presented.
► Along with advantages of SCR, key drawbacks include those related to ammonia slip.
► A membrane reactor is an option for the thermodynamically limited NH3 decomposition.
► The feasibility of using membrane reactors (MR) for NH3 decomposition is analyzed.
► The maximum conversions using MR are in the range of 1.5 < log(Pe) < 2 and 0.5 < log(Da) < 0.