A Ni-Mg-Al-Ca catalyst was prepared by a co-precipitation method for hydrogen production from polymeric materials. The prepared catalyst was designed for both the steam cracking of hydrocarbons and for the in situ absorption of CO2 via enhancement of the water-gas shift reaction. The influence of Ca content in the catalyst and catalyst calcination temperature in relation to the pyrolysis-gasification of a wood sawdust/polypropylene mixture was investigated. The highest hydrogen yield of 39.6molH2/g Ni with H2/CO ratio of 1.90 was obtained in the presence of the Ca containing catalyst of molar ratio Ni:Mg:Al:Ca=1:1:1:4, calcined at 500°C. In addition, thermogravimetric and morphology analyses of the reacted catalysts revealed that Ca introduction into the Ni-Mg-Al catalyst prevented the deposition of filamentous carbon on the catalyst surface. Furthermore, all metals were well dispersed in the catalyst after the pyrolysis-gasification process with 20-30nm of NiO sized particles observed after the gasification without significant aggregation.
Bibliographical noteFunding: Japan Society for the Promotion of Science (JSPS) (Grant-in-Aid for JSPS Fellows, 24-4996); Ministry of Education, Culture, Sports, Science and Technology (MEXT) of the Japanese Government (Grant-in-Aid for Scientific Research (A), 25241022); The Basque Government's research training grant (BFI2010-206); and the Ministry of Science and Education of the Spanish Government (Project CTQ2010-16133).
- nickel catalyst