A versatile strategy involving one-step desilication of coke-deposited spent zeolite catalyst was successfully developed to prepare hierarchical porous carbon monoliths (HPCMs). Such a strategy avoids the use of hard or soft templates and carbon sources, eliminates high temperature carbonization, simultaneously minimizing the emissions from processing spent catalysts. The resulting carbon exhibits a controlled morphology such as three-dimensional networks, hollow spheres or nanosheets, a high degree of graphitization and a multi-level porous structure. Its mesopore (2-50 nm) surface area can reach 522 m2 g-1 and both mesopore and macropore (50-350 nm) volumes are more than 1.0 cm3 g-1. Such hierarchical porous carbon was found to be a superior support for minimizing the nanoparticle size and enhancing the synergism of the Fe-K catalyst for promoting CO2 hydrogenation. Using such a catalyst results in increased conversion of carbon dioxide and enhanced selectivity of high value olefins (C2-4) and long-chain hydrocarbons (C5+).
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)