Novel Membrane Reactor Concepts for Hydrogen Production from Hydrocarbons: A Review

Membrane reactors are attracting increasing attention for ultrapure hydrogen production from fossil fuel, integrating catalytic reaction and separation processes into one single unit thus can realize the removal of hydrogen or introduction of reactant in situ, which removes the thermodynamic bottleneck and improves hydrogen yield and selectivity. In this review, the state-of-the-art concepts for hydrogen production through membrane reactors are introduced, mainly including fixed bed membrane reactors, fluidized bed membrane reactors, and micro-channel membrane reactors, referring higher hydrocarbons as feedstock, such as ethanol, propane, or heptane; novel heating methods, like solar energy realized through molten salt; new modular designs, including panel and tubular configurations; ultra-compact micro-channel designs; carbon dioxide capture with chemical looping; multifuel processors for liquid and/or solid hydrocarbons; etc. Recent developments and commercialization hurdles for each type of membrane reactor are summarized. Modeling the reactor is fundamental to explore complex hydrodynamics in reactor systems, meaningful to investigate the effects of some important operating factors on reactor performances. Researches for reactor modeling are also discussed. Reaction kinetics for hydrocarbons reforming and reactor hydrodynamics are summarized respectively. Cold model is introduced to investigate physical phenomena in reactors.