Ceria promoted phosphate‐zirconia supported Ni catalyst for hydrogen rich syngas production through dry reforming of methane

Abstract

Summary Ceria promoted phosphate‐zirconia supported nickel catalyst (10Ni1Ce/PZr; x = 0, 1, 1.5, 2, 2.5, 3, 5 wt%) are prepared and characterized by XRD, SEM, SEM‐EDX, CH4‐TPSR, NH3‐TPD, cyclic H2TPR‐CO2TPD‐H2TPR, and TPH. Ceria addition induces surface reducibility, exposes reduced phases of NiO and Ni2P2O7 as CH4 decomposition sites, and persuades additional CO2 adsorbed species as formate species over the catalyst surface. It also switches mobile oxygen in the lattice and thereafter oxide vacancy is replenished by oxygen from CO2 to a great extent. Altogether, 1 wt% ceria loading (10Ni1Ce/PZr) ensures more than 90% H2 yield (H2/CO = 0.96) whereas 2 wt% ceria loading inputs constancy in catalytic performance up to 440 min TOS. Up to 3 wt% ceria loading, 97% hydrogen yield (H2/CO ~1) is observed. Catalytic performance deteriorated above that 3 wt% ceria loading due to shading the catalytic active site or reoxidation of metallic nickel by excess ceria.

Role of Ca, Cr, Ga and Gd promotor over lanthana‐zirconia–supported Ni catalyst towards H2‐rich syngas production through dry reforming of methane

“…Non-promoted catalyst has stretching vibration peak of C-H at 2850 cm −1 and combination of asymmetric stretching of COO and bending vibration of C-H bond peak at absorption band at 2932 cm −1 . 16 On Ca, Gd, Ga promotional addition, absorption bands about 2850 and 2932 cm −1 are disappeared. On chromium promotional addition, the absorption bands at 1070 and 1368 cm −1 disappeared, whereas the absorption band at 915 cm −1 for stretching vibration of Cr=O, 58 2850 The SEM and EDX profiles of promoted and unpromoted catalysts are shown in Figure 7.…”

“…Ni-based catalyst incorporation of 9 wt.% P on ZrO 2 support provided more than one CH 4 decomposition site (as nickel metal and nickel phosphate), brought charge transfer band closer, physisorbed and chemisorbed (as carbonate and carboxylate) CO 2 species. 16 It showed a 76% H 2 yield with an H 2 / CO ratio of 0.95. 3 wt.% ceria promotional addition offers more CH x species held by surface with the different extents and inputs mobile lattice oxygen into the catalytic system for possible carbon deposit oxidation.…”

Hydrogen Production from Gadolinium-Promoted Yttrium-Zirconium-Supported Ni Catalysts through Dry Methane Reforming

“…The UV spectra and band gap of the 5Ni x Gd/Y + Zr ( x = 0, 1,2,3,4,5) catalyst system are shown in Figure . The zirconia-supported nickel fresh catalyst shows a peak at 230 nm for charge transfer of O –2 to Zr +4 , “258 and 286 nm” for charge transfer of O –2 to Ni +2 in the octahedral symmetry, , peaks at 371, 410, and 451 nm for the d–d transition from 3 A 2g to 3 T 1g (P) of Ni +2 in the octahedral environment, and peak at 717 nm for the d–d transition from 3 A 2g to 3 T 1g (F) of Ni +2 in the octahedral environment . Altogether, UV–vis spectra confirm the octahedral coordination of Ni in the zirconia-supported catalyst.…”

“…A nonmetal oxide−metal oxidesupported Ni catalyst, as well as nonmetal-promoted DRM catalyst systems, was also tried; however, we are limiting our literature to metal-promoted and binary metal oxide-supported DRM catalysts. 23,24 Gd was used as a spacer over iron oxide-based catalysts, which caused the increase in specific area. Its presence inhibited the reduction of Fe +3 to Fe +2 and the formation of iron carbide.…”

Comparative evaluation of Ni‐based bimetallic catalysts for dry reforming of methane at low temperature: The effect of alloy itself on performance

“…6 For these reasons, DRM is a promising solution to reduce carbon emissions and, at the same time, provides clean energy and industrially worthy chemicals. Therefore, diverse investigations and attempts to commercialize DRM have been conducted for several decades, 7,8 but there have been two critical problems disturbing DRM commercialization.…”