Highly pure hydrogen production via the thermocatalytic decomposition of methane over Ni/SiO2.MgO catalysts: Impact of the catalyst's chemical composition

Abstract

The goal of current research is to focus on exploring the effects of various MgO/SiO2 ratios, emphasizing their impact on the structure properties and advancing the catalytic activity and the chemical life span of Ni-catalysts by an exciting mixture of SiO2 and MgO to generate COx-bare hydrogen and nanocarbon simultaneously from methane decomposition reactions. SiO2/MgO mixed oxides with different ratios (0.5, 1, and 2) were ready via a facile co-precipitation method from magnesium nitrate and sodium metasilicate and used as supports for various nickel contents (30, 40, 50, and 60 wt%) followed by an impregnation technique. Different analytical techniques, such as XRD, BET, SEM, EDS, H2-TPR, and TPO, were used to characterize the catalysts before and after the catalytic runs. The prepared catalysts with various SiO2/MgO molar ratios depicted the BET surface area limiting from 37.9 to 143.4 m2 g−1, indicating remarkable surface improvements. The vast CH4 conversion of 64 % earned on the 50 wt% Ni/SiO2·MgO at 575 °C. Moreover, lower deactivation was detected regarding this catalyst at 600 min on stream.