Catalytic performance of cubic ordered mesoporous alumina supported nickel catalysts in dry reforming of methane

Continuous selective deoxygenation of palm oil for renewable diesel production over Ni catalysts supported on Al2O3and La2O3–Al2O3

“… 80,81 For the Ni/Al catalyst, the peak around 210 °C can likely be ascribed to atomic carbon deposits formed over metallic nickel (which is the most reactive carbon type to oxygen), while the shoulder around 475 °C can be attributed to amorphous coke deposited close to the metal support interphase. 82 The largest oxidation peak, at around 635 °C, can be linked to well defined-structured carbon, hard to be oxidized. For the Ni/LaAl catalyst, atomic carbon appears as a shoulder (at around 240 °C) of the peak located at 335 °C.…”

“…It is generally accepted in the literature that, in air rich environments, functional groups physically or chemically adsorbed onto carbon nanomaterials decompose below 200 C, amorphous carbon species combust at temperatures between 200-500 C, carbon nanobers (CNFs) and carbon nanotubes (CNTs) are burned between 500-600/ 650 C, and more graphitic structures such as graphite and graphene combust between 600/650-800 C. 80,81 For the Ni/Al catalyst, the peak around 210 C can likely be ascribed to atomic carbon deposits formed over metallic nickel (which is the most reactive carbon type to oxygen), while the shoulder around 475 C can be attributed to amorphous coke deposited close to the metal support interphase. 82 The largest oxidation peak, at around 635 C, can be linked to well dened-structured carbon, hard to be oxidized. For the Ni/LaAl catalyst, atomic carbon appears as a shoulder (at around 240 C) of the peak located at 335 C. The graphitic carbon peak at 630 C is signicantly less pronounced in comparison to the Ni/Al.…”

Modification Strategies of Ni-Based Catalysts with Metal Oxides for Dry Reforming of Methane

“…As well as the 2D morphology, by carefully controlling the pH value in synthesis, the formed mesoporous Al 2 O 3 with a cubic phase provided steric hindrance to confine the Ni metals within the support matrix. Owing to the strong resistance against coking and sintering, an excellent conversion of CO 2 and CH 4 were obtained (97% and 99%, respectively), with only 5% coke formation over a 210 h DRM reaction at 700 • C (Table 1) [31]. To simultaneously improve the Ni dispersion and mass diffusion, a hierarchically porous Al 2 O 3 structure with bimodal pore distribution (macropore structure and mesoporous channels) confined the Ni nanoparticles, and allowed the fast diffusion of intermediates and products, thus facilitating the CH 4 activation and carbon removal [57].…”

“…In addition to the CO 2 conversion, CH 4 prefers to adsorb onto the Ni surface and undergoes the activation to produce CH x and H atoms. Thus, a highly dispersed Ni particle with a small size and large exposed area favors a fast CH 4 conversion [31][32][33]. To ensure a well-distributed and unchanged particle size, metal oxides can be added to interact strongly with Ni sites by forming the solid solution or spinel phase.…”

Advanced Ordered Nanoporous Materials

“…The optimum catalyst converted almost 100% of the oil to linear paraffin with about 70% selectivity to C17 alkane. Gholizadeh et al developed cubic ordered mesoporous alumina (COMA)-supported nickel catalysts for dry reforming of methane (Gholizadeh et al 2021). In the 15% loading of Ni, the catalyst could convert more than 90% of CH 4 and CO 2 with excellent stability.…”