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A comprehensive investigation on the steam reforming of methanol (SRM) process using a microstructure monolith in conjunction with a synthesized nanostructure of TiO 2 is presented. The surface of the designed monolith/TiO 2 structure was coated with copper, copper/nickel, ruthenium, and platinum as the catalyst. The prepared catalysts were then characterized with FE-SEM, AFM, BET surface area measurement, FT-IR, far-infrared, temperature programmed reduction (TPR), and X-ray diffraction (XRD). The obtained results show that in this process, the designed Monolith/TiO 2 structure has a remarkable impact on methanol conversion (99%) and carbon monoxide selectivity (5%). These results are interpreted by the high surface area and superb mass transfer in this micro/nano engineered structure. These results also indicated that the catalyst activity and dispersion are influenced by the metal-support interaction, which is more pronounced in the TiO 2 supports. The ruthenium catalyst presented the highest conversion and selectivity for this process. However, the economically viable property of the Cu-Ni catalyst supposes it as an alternative for the noble ruthenium catalyst. [ABSTRACT FROM AUTHOR]

The performance of Cu-Ni/LaZnAlO and Cu-Ni/γ-AlO catalysts in the methanol reforming process in a monolith reactor in the temperature range of 200-350 °C, feed flow rate of WHSV = 20.8 h and atmospheric pressure has been investigated. In order to perform a more thorough investigation, surface area, morphology and crystalline structure of the synthetic catalysts have been studied using BET, FE-SEM, TPR, FT-IR, TEM, TGA and XRD analyses. The results have shown that Cu-Ni/LaZnAlO catalyst synthesized by combustion reaction method under ultrasound irradiation has a very high efficiency and catalytic activity, low reduction temperature, high mechanical resistance and large pore sizes. The latter causes a higher percentage of active metal impregnation and better distribution on the support, greater resistance against sintering and maintenance of catalyst inertness at temperatures over 1000 °C, in comparison with conventional catalysts such as Cu-Ni/γ-AlO. This make its substitution for currently used catalysts affordable. [ABSTRACT FROM AUTHOR]

Three novel M/ZnLaAlO 4 (M = 10%Ni, 3%Pt and 3%Ru) nanocatalysts as well as the common 10%Ni/γ-Al 2 O 3 sample were synthesized by the wet impregnation method and characterized by XRD, FE-SEM, TEM, temperature-programmed reduction (TPR), N 2 physisorption, FT-IR and TGA/DTA analyses. The catalytic activities of the four nanocatalysts were evaluated in dry (DRM), steam (SRM) and combined dry-steam (CRM) reforming of methane at atmospheric pressure, five various temperatures (600–800 °C) and three different GHSV values (3500, 7000, 10,500 h −1 ). Among the ZnLaAlO 4 supported catalysts, the greatest and the least catalytic performances were measured for the 3%Ru/ZnLaAlO 4 and the 3%Pt/ZnLaAlO 4 , respectively. Surprisingly, the TGA diagrams of the used nanocatalysts almost did not illustrated coke formation for the 3%Ru/ZnLaAlO 4 and 3%Pt/ZnLaAlO 4 (especially in the SRM process) that were supported by their FE-SEM images which did not display carbon deposition. All of the three ZnLaAlO 4 supported catalysts revealed much higher catalytic activity and less coke content compared with the commercial 10%Ni/γ-Al 2 O 3 catalyst. Thus, we believe that (to the best of our knowledge) this is the first time that such extremely active noble nanocatalysts are obtained with exceptionally high resistance against carbon deposition on their surfaces. The very low onset reduction temperatures in the TPR profiles of the 3%Ru/ZnLaAlO 4 , 3%Pt/ZnLaAlO 4 and 10%Ni/ZnLaAlO 4 at 230, 264, 333 °C, respectively, reflected the convenient reducibility properties of these samples. Considering the catalytic efficiency and resistance against coke formation, the 3%Ru/ZnLaAlO 4 was chosen as the best nanocatalyst for the DRM, SRM and CRM reactions among our four tested samples. [ABSTRACT FROM AUTHOR]

The pervasive generation of sewage sludge (SES) and deficiencies in its disposal methods have resulted in several significant environmental and human health challenges. This study explored the catalytic effect of nickel (Ni)-based CeO 2 , ZrO 2 , Zr 0 . 8 Ce 0 . 2 O 2 , Zr 0 . 4 Ce 0 . 6 O 2 , and γ-Al 2 O 3 supports in fixed beds and foam reactors in the steam gasification of SES. A comparison of the hydrogen selectivity and gas yield of the synthesized catalysts confirmed that the metal composite support, especially Zr 0 . 8 Ce 0 . 2 O 2 , had a positive effect on the catalytic activity and stability. This can be attributed to the enhanced oxygen vacancies and oxygen mobility, resistance to coke deposition, uniform morphology, improved dispersion, and increased number of Ni sites on the Zr 0 . 8 Ce 0 . 2 O 2 support. Furthermore, foam reactors offer unique advantages in improving hydrogen production. This study provides an advanced strategy for SES valorization that fulfills the requirements of an economically and environmentally sustainable technology., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

In this study, nickel-loaded perovskite oxides catalysts were synthesized via the impregnation of 10%Ni on XTiO 3 (X = Ce, Sr, La, Ba, Ca, and Fe) supports and employed in the catalytic steam gasification of swine manure to produce H 2 -rich syngas for the first time. The synthesized catalysts were characterized using BET, H 2 -TPR, XRD, HR-TEM, and EDX analysis. Briefly, using perovskite supports resulted in the production of ultrafine catalyst nanoparticles with a uniform dispersion of Ni particles. According to the catalytic activity test, the gas yield showed the increment as 10% Ni/LaTiO 3 < 10% Ni/FeTiO 3 < 10% Ni/CeTiO 3 < 10% Ni/BaTiO 3 < 10% Ni/SrTiO 3 < 10% Ni/CaTiO 3 . Meanwhile, zero coke formation was achieved due to the oxygen mobility of prepared catalysts. Also, the increase in the H 2 production for the applied catalysts was in the sequence as 10% Ni/CeTiO 3 < 10% Ni/FeTiO 3 < 10% Ni/LaTiO 3 < 10% Ni/BaTiO 3 < 10% Ni/SrTiO 3 < 10% Ni/CaTiO 3 . The maximum H 2 selectivity (∼48 vol%) obtained by10% Ni/CaTiO 3 was probably due to the synergistic effect of Ni and Ti on enhancing the water-gas shift reaction, and Ca on creating the maximum oxygen mobility compared to other alkaline earth metals doped at the A place of perovskite. Overall, this study provides a suitable solution for enhanced H 2 production through steam gasification of swine manure along with suggesting the appropriate supports to prevent Ni deactivation by lowering coke formation at the same time., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)