To improve hydrogen production performance of self-heating methanol steam reforming (MSR) microreactor, a novel nickel foam with multiple microchannels was proposed as combustion reaction support. A wall temperature comparison of the methanol combustion microreactors with nickel foam catalyst support and particles catalyst support in the combustion reaction process was performed. According to the numerical simulation results of combustion reaction of nickel foam, the shape and size of multiple microchannels of nickel foam were determined. The laser processing was then used to fabricate the multiple microchannels of nickel foam. The experimental results show that the methanol combustion microreactor with nickel foam loaded with Pt catalyst exhibits similar wall temperature distribution with the methanol combustion microreactor with 2 O 3 particles reaction support. Compared with the nickel foam without microchannel, the T max (maximum temperature difference) and the maximum in the temperature distribution of nickel foam with multiple microchannels decreased respectively by 57.8% and 33.8 when 1.1 mL/min methanol flow rate was used.Hydrogen production performance of self-heating MSR microreactor using the nickel foam with multiple microchannels increased by about 21% when 430 reforming temperature and 4 mL/h methanol-water mixture flow rate were performed.

To decrease the temperature difference per unit temperature (ΔTA) of an autothermal methanol steam reforming (ATMSR) microreactor for hydrogen production (HP) and enhance its long-term HP performance for supplying long-term stable hydrogen source for fuel cell vehicles, a threedimensional (3D)-printed regular-porous structure with multiple microchannels is developed as combustion reaction support (CRS) of the ATMSR microreactor. A regular-porous structure with multiple microchannels is designed as CRS based on the temperature distribution model of methanol combustion (MC) reaction support established according to the MC reaction mechanism. Reactant concentration and temperature distributions of the regular-porous CRSs with various multiple microchannels are studied by numerical simulation. Combustion performances of regular-porous CRS with optimized multiple microchannels, nonoptimized regular-porous CRS, and nickel foam CRS with optimized multiple microchannels are compared by experiments. HP performances of ATMSR microreactors with the optimized and nonoptimized regular-porous CRSs are also compared. The results show that compared to the nonoptimized regular-porous CRS and the optimized nickel foam CRS, the ΔTA of the optimized regular-porous CRS decreases by 58.6 and 15.6%, respectively. Due to the less carbon deposition and particle agglomeration of the HP catalyst realized by the optimized regular-porous CRS, the ATMSR microreactor with the CRS can display better long-term HP performance. This research work offers a new method for enhancing the long-term HP performance of the ATMSR microreactor.

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