Monolithic SiC-foam supported Ni-La2O3 composites for dry reforming of methane with enhanced carbon resistance

• Published in: Fuel processing technology 2021-02, Vol.212, p.106627, Article 106627
• Main Authors: Zhang, Zhige, Zhao, Guofeng, Bi, Guican, Guo, Yunyv, Xie, Jun
• Format: Article
• Language: English
• Subjects: Aluminum oxide; Carbon dioxide; Carbon resistance; Catalysts; Citric acid; Coke; Dry reforming of methane; La2O3 additive; Lanthanum; Lanthanum oxides; Methane; Nanocomposites; Ni catalyst; Ni sintering; Nickel oxides; Reforming; SiC-foam; Silicon carbide; Sintering
• ISSN: 0378-3820; 1873-7188
• DOI: 10.1016/j.fuproc.2020.106627

A monolithic silicon carbide foam (SiC-foam) structured nickel and lanthanum oxide (Ni-La2O3) nanocomposite catalyst is developed via reducing the nickel oxide and lanthanum oxide (NiO-La2O3) precursor that can be grown onto SiC-foam surface by depositing the needed citric acid gel followed by calcination at 750 °C. By taking the advantages of homogeneous component-distribution and strong Ni-La2O3 interactions in the Ni-La2O3 nanocomposites, this catalyst delivers much enhanced coke-depositing/Ni-sintering resistance than the unmodified counterpart of Ni-La2O3/alumina (Al2O3) in the titled reaction. At 850 °C, a weight hourly space velocity (WSHV) is set as 24,000 mLCH4-CO2 gCat−1 h−1, methane/carbon dioxide (CH4/CO2) conversions of 71/85% are initially achieved on the Ni-La2O3/SiC-foam catalyst followed by progressively decreased to 60/72% within 50 h (h), but remain almost unchanged for the next 50 h. On the contrary, the CH4/CO2 conversions on the Ni-La2O3/Al2O3 catalyst rapidly drop from 49/71% to 24/40% within only 25 h due to its serious Ni-sintering and coke deposition. The presence of SiC-foam and the synergistic effect of nickel‑lanthanum play an important role in the dry reforming of methane. The carbon resistance ability of catalysts makes it still have high activity after 100 h stability test. [Display omitted] •This paper provides theoretical support for biogas conversion into syngas.•A novel monolithic SiC-foam supported Ni-La2O3 composites were synthesized.•SiC-foam has excellent thermal conductivity that resists cold-spots formation.•Ni-La2O3/SiC-foam has remarkable resistance to Ni sintering.•High carbon resistance is due to the synergies between Ni-La2O3 and SiC-foam.