Catalysis Today
Catalysis Today
5 years ago

CO2 methanation over Ni catalysts based on ternary and quaternary mixed oxide: a comparison and analysis of the structure-activity relationships

CO2 methanation over Ni catalysts based on ternary and quaternary mixed oxide: a comparison and analysis of the structure-activity relationships
Methanation of CO2 was studied in a high throughput reactor (Amtech SPIDER 16) over Ni catalysts supported on ternary and quaternary alumina-zirconia-titania-ceria mixed oxides, in order to compare them under industrial relevant conditions and derive indications about the structure-activity relationships and specifically the role of ceria. The samples were characterized by BET, XRD, H2-TPR, CO-chemisorption, XPS and CO-TPD analyses. Catalytic activity was evaluated towards CO2 methanation at 5bar pressure, temperature range of 300–400°C and different Gas Hourly Space Velocities (GHSVs). The results showed that enhanced catalytic activity depends on both textural improvements (for the ternary oxide supported Ni) and reducibility and metal dispersion (for the quaternary oxide supported Ni). The comparison between both groups of catalysts revealed that addition of CeO2 to 20%Ni/Al2O3-ZrO2-TiO2 further improves the catalytic performance. The catalyst supported on a mixed oxide support with 15wt% of ceria, titania and zirconia (the remaining 55% is alumina) exhibits the highest CO2 conversion (82%) and methane selectivity (98%) at 350°C and GHSV of 4000h−1. The role of CeO2 as promoter is to increase Ni dispersion and stabilize the presence of β-type NiO species which are reduced at lower temperatures. Other promoters (TiO2, ZrO2) have mainly a textural effect. Moreover, CeO2 promotes also the stability decreasing the deactivation rate of about one order of magnitude with respect to the best ternary system (Ni/C5) investigated.

Publisher URL: www.sciencedirect.com/science

DOI: S0920586117305916

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.