Dry Reforming of Methane over Ni–Fe–Al Catalysts Prepared by Solution Combustion Synthesis
Alua M. Manabayeva, Päivi Mäki‐Arvela, Zuzana Vajglová, Mark E. Martínez‐Klimov, Teija Tirri, Tolkyn S. Baizhumanova, V. P. Grigor’eva, Manapkhan Zhumabek, Yermek Aubakirov, Irina L. Simakova, Dmitry Yu. Murzin, С.А. Тунгатарова
Abstract
High Resolution Image Download MS PowerPoint Slide Dry reforming of methane (DRM) is a promising method to utilize two greenhouse gases, such as CH 4 and CO 2, to produce synthesis gas. In the current work, both monometallic Ni and bimetallic Ni–Fe catalysts with different Fe/Ni molar ratios, synthesized by solution combustion synthesis (SCS) in DRM, were investigated using a feed ratio of CH 4 /CO 2 /Ar of 1:1:1 at 600–900 °C. The catalysts were characterized by several physicochemical techniques such as X-ray diffraction (XRD), scanning electron microscopy energy-dispersive X-ray (SEM-EDX) spectroscopy, transmission electron microscopy (TEM), CHNS, N 2 physisorption, H 2 -TPR, O 2 -TPO, NH 3 -TPD, and thermogravimetric analysis (TGA). One of the highest hydrogen yields of 81% was obtained at 93% conversion of CH 4 and 94% conversion of CO 2 for the bimetallic 15Ni–5Fe–30Al catalyst, which contained, according to XRD, NiAl 2 O 4 spinel and metallic Ni phases. The spinel phase was decomposed during the reaction, while the Ni 3 Fe alloy was formed. Catalysts with a higher Fe/Ni ratio exhibited lower conversion and contained an inactive FeAl 2 O 4 spinel. Rather stable yields of CO and H 2 were obtained in an experiment with 20 h time-on-stream.