Optimization and analysis of biomass carbon loaded metal catalyst for catalytic cracking of toluene

Abstract

The technology of hydrogen production from biomass pyrolysis is on the way, but the biomass tar produced in the process of pyrolysis seriously affects its practical application. The key to catalytic cracking technology was to develop highly low-temperature active and stable catalysts. In view of that, a new anti-sintering carbon-based nanocatalyst with distinct micro-mesoporous structure was synthesized by carbothermic reduction of the catalyst under mixed gas (H2/N2) atmosphere using cigarette stalks as raw material. The results showed that at a relatively low temperature of 700 °C, the catalyst had a high toluene conversion of 100 %, a stable lifetime of 250 min, a maximum hydrogen yield of 12,250 ppm and a desirable hydrogen selectivity of 77 %. The addition of hydrogen during the catalyst synthesis enabled a stronger interaction between the metal and the carbon support, which maintained a high metal distribution, resulting in a more interesting anti-sintering phenomenon of nickel nanoparticles at high temperatures. In particular, hydrogen etching of the support avoided collapse of the pores at high temperatures. At the same time, the etching enriched the pore structure of the support, thus increasing the specific surface area and pore volume of the support. This study provided a simple treatment of a carbon loaded nickel catalyst in the synthesis process and reported a novel low-temperature catalytic cracking catalyst with good toluene cracking activity and hydrogen generation.