DME conversion using high flux tubular membrane reactors

High flux tubular membrane reactors were designed for dimethyl ether (DME) steam reforming. Considering the facile scale-up and high flux of hydrogen, tubular stainless steel supports were employed for the membrane reactors. At 500°C, DME conversion reached ~100%, while hydrogen recovery reached 20%. However, contamination by CO was rather high (>1%), making this process unsuitable for proton exchange membrane fuel cell applications, which require a CO concentration of <100 ppm. This result showed that an additional polishing step was needed to reduce the CO concentration. Membrane reactors were further modified to perform an water–gas shift reaction on the permeate of the membrane reactors by employing a fixed bed reactor, which yielded high-purity hydrogen (~99%) along with a low CO content (<20 ppm).