Promoting Effect of CeO₂and MgO for CO₂Reforming of Methane over Ni-ZnO Catalyst

Abstract

The purpose of this study was to find out the effect of CeO2 and MgO (as a promoter) on CO2 reforming of methane or dry reforming of methane (DRM) for the production of synthesis gas. In this aspect, CeO2 and MgO promoted Ni‐nanoparticles supported ZnO catalyst was prepared by surfactant induced hydrothermal method, using cetyltrimethylammonium bromide (CTAB) as surfactant, morphology controlling agent and polyvinylpyrrolidone (PVP) as size controlling agent. The prepared catalysts were characterized by BET‐Surface area, X‐ray diffraction study (XRD), Scanning Electron Microscropy (SEM), Transmission Electron Microscopy (SEM), Inductively coupled plasma atomic emission spectroscopy (ICPAES), Temperature Programmed Reduction (TPR), X‐ray Photoelectron Spectroscopy (XPS) and Thermogravimetric Analysis (TGA) techniques. Highly basic nature of MgO and excellent redox properties of CeO2 increased nickel dispersion and created strong metal‐support interaction, which effectively reduced the coke deposition on the catalyst surface. MgO promoted Ni‐ZnO catalyst showed better low temperature activity compared to CeO2 promoted Ni‐ZnO catalyst for DRM and Ni‐MgO/ZnO catalyst also exhibited better coke resistivity, because of comparatively smaller nickel nanoparticles. Both the promoted catalysts showed more than 24 h of time on stream (TOS) stability at 800 °C without any significant deactivation of the catalysts. The catalysts produced H2/CO ratio 0.99 at 800 °C during the TOS.

Surfactant‐Induced Preparation of Highly Dispersed Ni‐Nanoparticles Supported on Nanocrystalline ZrO2for Chemoselective Reduction of Nitroarenes

“…TGA analysis was carried to check the thermal stability of catalyst. From the TGA plot of as‐prepared catalyst (4.9% Ni‐ZrO 2 HT ), two regions of weight loss was seen, in which first weight loss (6%) was around 50 °C–200 °C indicating presence of physisorb water and second weight loss (∼1.3%) was around 250 °C–500 °C, due to decomposition of Ni(OH) 2 to NiO, and H 2 O and /or hydrogen containing carbon species (CTAB, PVP), as presented in Figure S8. After 550 °C, negligible weight loss confirmed thermal stability of prepared catalyst.…”

“…So, a general and simple strategy is highly desirable for synthesis of supported nanostructure materials. During last few years, our group is engaged in developing surfactant induced preparation of Cu, Ag and Pt based nanomaterials supported on different nanostructured oxides like Cr 2 O 3 , WO 3 , CeO 2 , Mn 3 O 4 , etc in a single preparation method . We report here highly dispersed Ni‐nanoparticles supported on nanocrystalline ZrO 2 in a single preparation method for chemoselective hydrogenation of nitroarenes, at 60 °C under 1.0 MPa H 2 in water .…”

Catalytic performance of Ni supported on ZnO‐Al2O3 composites with different Zn content in methane dry reforming

“…Sublimation of ZnO starts at about 380 °C . The performance of Ni–ZnO catalysts promoted by MgO and CeO 2 was investigated at low temperature DRM by Singha et al . Sokolov et al .…”

Understanding the performance and mechanism of Mg-containing oxides as support catalysts in the thermal dry reforming of methane

“…Recently, numerous attempts have been made to minimize carbon deposition on the catalyst surface in a DRM reaction. A high dispersion of active metal over the support is an effective approach to decrease carbon deposition by producing catalysts of small particle size [ 19 , 28 , 31 , 34 – 40 ]. In addition, a high dispersion of metal particles enhances the interaction between metal and support, consequently reducing carbon deposition [ 40 – 44 ].…”