Search Results (4)

This work presents, for the first time, the comparative physicochemical and reactivity studies of a range of bimetallic Pt-Ni, Pd-Ni, Ru-Ni, and Ag-Ni catalysts in the oxy-steam reforming (OSR) of liquefied natural gas (LNG) reaction towards hydrogen generation. In order to achieve the intended purpose of this work, a binary oxide CeO₂·ZrO₂ (1:2) support was prepared via a co-precipitation method. The catalysts’ physicochemical properties were studied using X-ray diffraction (XRD), BET, TPR-H₂, TPD-NH₃, SEM-EDS and XPS methods. The highest activity in the studied process was exhibited by the 1%Pt-5%Ni catalyst supported on CeO₂·ZrO₂ (1:2) system. The highest activity of this system is explained by the specific interactions occurring between the components of the active phase and between the components of the active phase and the carrier itself. The activity results showed that this catalytic system exhibited above 71% of the methane conversion at 600 °C and 60% yield of hydrogen formation. The results of this work demonstrate that the Pt-Ni and Ru-Ni catalytic systems hold promise to be applied in the production of hydrogen to power solid oxide fuel cells. Full article

The oxy-steam reforming of liquefied natural gas reaction (OSR-LNG) is promising process for syngas generation. In this paper, the catalytic properties of NiO/La₂O₃ systems prepared by wet impregnation and co-precipitation methods were extensively investigated in OSR-LNG reaction. The physicochemical properties of the studied catalytic materials were determined using various techniques including Temperature programmed reduction (TPR-H₂), Temperature programmed desorption (TPD-NH₃), Brunauer, Emmett and Teller (BET), X-ray diffraction (XRD) and Scanning electron microscopy (SEM) with an energy dispersive X-Ray spectrometer (EDS). Reactivity measurements performed in the OSR-LNG process showed that the catalyst preparation method and the calcination temperature significantly affected the activity of NiO/La₂O₃ catalysts in the OSR-LNG reaction. The catalytic activity tests showed that NiO/La₂O₃ system prepared by a wet impregnation method and calcined at 700 °C showed the total conversion of the LNG component at 900 °C and the highest H₂ yield at 700 and 900 °C. The phase composition studies confirmed the formation of the LaNiO₃ structure in the case of the NiO/La₂O₃ catalyst prepared by wet impregnation, calcined at the temperature of 700 °C. Catalytic activity measurements showed that the reactivity of the catalysts was related to their phase composition and acidity. SEM images of spent catalysts showed that the smallest amount of carbon deposit was detected on the surface of the most active systems. Full article

Nowadays, the reforming of natural gas is the most common of hydrogen or syngas generation process. Each reforming process leads to the achievement of specific goals and benefits related to investment costs. The disadvantage of the reforming process is the need to preclean it mostly from the sulfur and nitrogen compounds. The solution to this problem may be liquefied natural gas (LNG). Liquefied natural gas has recently been seen as an energy source and may be a promising replacement for natural gas. The constant development of the pipeline network, safe transport and a lot of advantages of LNG were contributed to the research development related to the usage of LNG in energy generation technologies. The presented review is a literature discussion on the processing of methane used to produce hydrogen with particular emphasis on the processes of oxy-steam reforming of natural or liquefied natural gas (OSR-LNG). In addition, a key consideration in this article includes Ni catalyst systems used in the oxy-steam reforming of methane or LNG reactions. An analysis of the OSR process conditions, the type of catalyst and the OSR of the methane reaction mechanism may contribute to the development of a modern, cheap catalyst system, which is characterized by high activity and stability in the oxy-steam reforming of natural gas or LNG (OSR-LNG). Full article

This work presents, for the first time, the catalytic studies of bimetallic Ag-Ni catalysts in the oxy-steam reforming (OSR) of liquefied natural gas (LNG) to hydrogen generation. The physicochemical properties of monometallic Ni and bimetallic catalysts were investigated using various techniques, such as: BET, TPR-H₂, TPD-NH₃, XRD, TG and SEM-EDS. The catalytic studies showed that the promotion of 20% Ni/ZrO₂ catalyst by silver (by 1 or 2 wt.%) improves the efficiency of the produced hydrogen in the oxy-steam reforming of LNG at high temperature. The promotional effect of silver on the reducibility of a Ni/ZrO₂ catalyst has been proven. The interactions between Ag and Ni have been proven, and explain the catalytic activity of the catalysts in the investigated processes. TG-DTA-MS results obtained for the spent catalysts proved that the small addition of silver to monometallic nickel catalyst reduces the amount of the carbon deposit formed on the catalyst surface during the oxy-steam reforming of LNG process. Obtained results in this work confirmed that liquid natural gas processing may become an alternative to fossil fuels and confirmed the validity of the hydrogen production via oxy-steam reforming of LNG. Full article