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A novel method of triple line focused on solar-powered receiver/reactor with a thermal storage medium for methanol steam reforming (MSR) hydrogen production is proposed in this paper. The photo-thermal-chemical energy conversion and coupling equations of the receiver/reactor are established, and the dynamic regularity between solar radiation and the hydrogen production characteristics is obtained by numerical simulation. The results show that a high solar radiation intensity helps to stabilize the duration of the reaction. For every 100 W m−2 increase in the solar radiation intensity, the duration of the reaction maintained at the phase change point temperature of the phase change material (PCM) increases by approximately 11%. The daily hydrogen production performance of the system in Kunming (102°43′E and 25°02′N) during typical solar days is studied. The average annual total hydrogen production per unit of the lighting area is approximately 1300 m3. This research can guide similar issues related to solar thermochemical technology. • A novel method of triple line focused on solar reactor/receiver is proposed. • A comprehensive model of solar-driven adapted to different powers is established. • Dynamic regularity of hydrogen production rate with solar radiation is revealed. • System goes well when solar radiation is 400 W m−2 or above on partly cloudy skies. [ABSTRACT FROM AUTHOR]

Abstract: An experimental and analytical study of nanocatalyst fabrication and the production of hydrogen utilizing photon energy was carried out. The porous structure of the nanocatalyst provides a high surface to volume ratio of the catalytic layer thereby increasing the activity of the catalyst. An experiment was carried out to obtain an effective nanocatalyst by using pulsed laser ablation (PLA) technology. The properties of the nanocatalyst are directly related to the performance of the catalytic reaction and are analyzed. Experiments and analyses were carried out to evaluate the activity enhancement of the nanocatalyst. Photonic energy provides the heat for the endothermic steam–methanol reforming reaction producing hydrogen. It is shown that photonic induced steam–methanol reforming in a nanocatalyst reformer is feasible and promising. [Copyright &y& Elsevier]

Abstract: An experimental and theoretical study of steam reforming of methanol is carried out in a packed-bed microreactor with internal heating. Experimental results of the methanol conversion and carbon monoxide concentration in an internally heated reformer are compared with those of an externally heated reformer. Higher methanol conversion and carbon monoxide concentration are obtained for internal heating at the same conditions. The results show the conversion efficiency of methanol and CO concentration increase with increasing internal heating rate over the range of operating conditions. A correlation for the conversion efficiency of methanol has been obtained as a function of the internal heating rate and a dimensionless time parameter which represents the ratio of the characteristic time of the methanol flow to the time for chemical reaction. [Copyright &y& Elsevier]

Abstract: Steam reforming of methanol is investigated numerically considering both heat and mass transfer of the species in a packed bed microreactor. The numerical results are shown to be in good agreement with experimental data [M.T. Lee, R. Greif, C.P. Grigoropoulos, H.G. Park, F.K. Hsu, J. Power Sources Transport in, 166 (2007) 194–201] with a BASF F3-01(CuO/ZnO/Al2O3) catalyst. A correlation for the conversion efficiency of methanol has been obtained as a function of the operating temperature and a dimensionless time parameter which represents the ratio of the characteristic time of the methanol flow to the time for chemical reaction. The results show that for the constant wall temperature condition the steam reforming process of methanol results in a nearly uniform temperature throughout the microreactor over the range of operating conditions. [Copyright &y& Elsevier]

We have fabricated CuO/ZnO nanowire (NW) catalyst for hydrogen production by solar thermal steam-methanol reforming (SMR). Such NW catalyst is expected to be more durable than the conventional nanoparticle catalysts by avoiding agglomeration. ZnO NWs are synthesized by hydrothermal growth on quartz and glass substrates. The ZnO NWs are then coated with CuO by thermal decomposition of copper nitrate using UV pulsed laser as a heat source for prototyping. A solar simulator is used as a heat source for the demonstration of the SMR in water/methanol mixture solution. Gas chromatograph (GC) exhibits increasing mole fraction of produced hydrogen with irradiated time. We then fabricate the catalyst on a large area glass plate substrate by the CuO deposition using an electric heater to confirm the SMR and demonstrate scaling-up. The SMR is briefly demonstrated by feeding water vapor/methanol mixture gas to the catalyst heated by an electric heater, giving thermally produced hydrogen (CO/H 2 = 0.019) in the product gas detected by GC. [ABSTRACT FROM AUTHOR]