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Hydrogen is a potential energy carrier in comparison to conventional fuels due to its high energy content. Methane is an attractive source for 'on‐site' production of hydrogen by using membrane reformer due to its low cost. However, such reformers are not well studied and high temperature operation of steam methane reforming (SMR) makes the integration with membrane separation difficult. Further, the main product of SMR is CO and H2 in which CO has an inhibition effect on the membrane separation process. Therefore, it is vital to synthesize a low temperature and low CO selective catalyst for a suitable integration with membrane reformer. Nickel‐based catalyst is widely used for SMR due to its low cost and high catalytic activity. CeO2 is a favoured support as it mobilizes the lattice oxygen and reduces the coke formation and CO selectivity. Though several studies are reported on CeO2 based support, the effect of CeO2 surface morphology is not studied for SMR. In the current work, Ni/CeO2 of different shapes (nanocube and nanorod) are synthesized. The complete characterization of the support was performed. The effect of support shape, calcination temperature, and reduction temperature on SMR activity is found at different operating temperatures. For each condition conversion, CO, CO2 selectivity, and hydrogen yield are calculated. The results show the CeO2 morphology has a considerable effect on conversion, CO selectivity, and hydrogen yield. It is found that ceria nanocube calcined at 550°C provides better performance at high temperature. [ABSTRACT FROM AUTHOR]

Membrane reformers emerge as an efficient technology for 'on‐site' ultra‐pure hydrogen production. The membrane reformer can be integrated with PEM fuel cell (PEMFC) to provide power. However, as the PEMFC works at lower temperature hence, such integration requires a low temperature catalyst. Further, for successful integration of membrane reformer with PEMFC, a low CO selective catalyst is vital. In current work, Ni‐based alumina and ceria supported catalysts are used. The effect of La and Fe promoters on the performance of Ni‐based alumina and ceria supported catalysts are investigated. The catalysts are synthesized using wet impregnation method. A complete characterization of catalysts is performed using BET, XRD, FESEM, and EDX. Fe promoted catalysts shows low CO and high CO2 selectivity which is desirable for membrane reformer. However, the catalytic activity of Fe promoted Ni‐based alumina and ceria supported catalysts were low. La promoted Ni‐based catalysts show high catalytic activity on both alumina and ceria supported catalysts. La promoted catalysts also gives low start up time, high catalytic activity and low CO selectivity at low temperature. Ni−La/Al2O3 catalyst provides 50 % conversion and 12 % CO selectivity at 500 °C. This makes it suitable for 'on‐site' generation of ultra‐pure hydrogen through membrane reformer. [ABSTRACT FROM AUTHOR]

Methanol steam reforming (MSR) has gained significant attention for in-situ hydrogen (H 2) production. To overcome the high energy requirement in the process, two modified methods such as combustor integrated steam reforming (CISR), and sorption enhanced chemical looping steam reforming (SE-CLSR) are widely used for the production of H 2. In the present work, a techno-economic comparison of CISR and SE-CLSR models has been carried out using Aspen Plus V11to assess the economic viability of hydrogen generation by MSR process. SE-CLSR model is developed considering NiO as an oxygen transfer material (OTM). Simulations have been performed to observe a strong dependence of methanol conversion, hydrogen yield, CO selectivity with different operating conditions like temperature, steam to methanol (S/M) ratio, catalyst weight to methanol molar ratio. The sensitivity analysis of the considered models is performed to obtain the optimum operating conditions. The hydrogen production cost is estimated as 2.66 $/kg and 2.79 $/kg from CISR and SE-CLSR processes, respectively. [Display omitted] • CISR and SE-CLSR models are developed for MSR in ASPEN Plus. • The sensitivity analysis of the two models is performed. • Techno-economic-evaluation of the developed processes is carried out. • The hydrogen production cost is found to be 2.66–2.79 $/kg. [ABSTRACT FROM AUTHOR]

The current work investigates various bimetallic catalysts supported on Al2O3−Zn−ZrO2 to determine a catalyst with minimal CO selectivity at high temperature for methanol steam reforming. Characterization tools employed in this study include temperature programmed reduction, X‐ray diffraction, X‐ray photoelectron spectroscopy and transmission electron microscopy. Activity testing for all the catalysts synthesized were performed in the temperature range of 150 to 500 °C. Bimetallic catalyst with addition of Fe as second metal to Cu in 50 : 50 molar ratio was observed with an interesting synergy which resulted in reduced particle size and enhanced reducibility. It was further observed that Cu−Fe with lower Fe content and up to 75 % Cu led to zero CO selectivity for temperature up to 450 °C. A structure‐activity relationship of Cu−Fe/Al2O3−Zn−ZrO2 was therefore elucidated. Further, reaction mechanism for the same was also proposed based on in‐situ diffuse reflectance infrared Fourier transform spectroscopy. [ABSTRACT FROM AUTHOR]