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A series of bimetallic oxide catalysts CuO-Y 2 O 3 were synthesized by different sol-gel methods for methanol steam reforming (MSR). The performance of the synthesized catalyst was investigated by characterization of X-ray diffraction, Brunauer-Emmett-Teller, scanning electron microscopy, transmission electron microscope, and X-ray photoelectron spectrometer techniques. The effects of different complexing agents on the property of the CuO-Y 2 O 3 were identified. The results showed that CuO-Y 2 O 3 synthesized by citric acid-EDTA as a complexing agent showed the best performance, which has the largest specific surface area and shows the highest dispersion of particles and lowest average size than others. The relatively large specific surface area could increase the contact area between the catalyst and the feed, thereby improving the catalytic performance of the catalyst. Moreover, without hydrogen reduction treatment, the selectivity of hydrogen to CuO-Y 2 O 3 can reach more than 99%, whereas the selectivity of CO is only 0.3% (under the reaction conditions: temperature of 300 • C, the ratio of water to methanol of 4:1, feed flow rate of 4 ml/h). The addition of yttrium enhances the interaction of the two active components, copper and yttrium, thereby preventing the migration of the active components. This work provides a potential and economical Cu-Y oxide catalyst for onboard in situ hydrogen production from MSR, because it can reduce the hydrogen reduction process time.

In this study, a series of A-site strontium-doped La1-xSrxCeO3-δ (x = 0.2, 0.4, 0.6, 0.8) perovskite catalysts were synthesized via the ethylenediaminetetraacetic acid (EDTA) sol-gel method for hydrogen production by methanol steam reforming. The fresh and the reduced catalysts are characterized by scanning X-ray (XRD), energy dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) techniques. Results showed that La0.6Sr0.4CeO3-δ exhibited the best performance among the La1-xSrxCeO3-δ catalysts. The operating parameters were optimized to study the catalytic performance of La0.6Sr0.4CeO3-δ, including catalytic temperature, water–methanol ratio (W/M) and liquid hourly space velocity (LHSV). However, the excessive strontium content led to a decrease in hydrogen production amount per unit time, and the high W/M promoted the reverse water–gas shift reaction (RWGS), which resulted in a decrease in CO selectivity and an increase in CO2 selectivity. In addition, the optimal reaction parameters are as follows: reforming temperature of 700 °C; W/M of 3:1; LHSV of 20 h−1. Furthermore, the methanol conversion rate of La0.6Sr0.4CeO3-δ can reach approximately 82%, the hydrogen production can reach approximately 3.26 × 10−3 mol/g(cat)/min under the optimum reaction conditions. Furthermore, La0.6Sr0.4CeO3-δ exhibits high hydrogen selectivity (85%), which is a promising catalyst for MSR application.

Summary Methanol steam reforming (MSR) is a promising method for hydrogen production from renewable energy. The effect of λ‐Al2O3 support derived from metal‐organic frameworks (MOFs) aluminum fumarate (A520) on the performance and stability of LaNi0.4Al0.6O3‐δ for MSR is investigated. Results demonstrate that compared with LaNi0.4Al0.6O3‐δ, LaNi0.4Al0.6O3‐δ/λ‐Al2O3 can achieve complete conversion of methanol and excellent thermal stability due to the higher SBET and strong interaction between the metal components and λ‐Al2O3. Characterization results indicate that the LaNi0.4Al0.6O3‐δ/λ‐Al2O3 catalyst, which was not successfully reduced due to its robust structure, still has active sites for the MSR reaction. This characteristic of the catalyst has the potential to be applied for onboard in‐situ hydrogen production, because it can shorten the time of hydrogen reduction process. Furthermore, the effects of catalytic temperature, feed water‐methanol ratio, and liquid hourly space velocity on performance of LaNi0.4Al0.6O3‐δ/λ‐Al2O3 are studied in detail and the optimal conditions ​​are determined and applied for stability tests.