New Strategy for High-Performance Integrated Catalysts for Cracking Hydrocarbon Fuels

In this study, we described the synthesis, characterization, and application of hyperbranched polymer-encapsulated metal nanoparticles (HEMNs) as integrated catalysts for supercritical cracking of hydrocarbon fuels. The metal precursor was extracted into the organic phase using a hydrocarbon-soluble hyperbranched poly(amidoamine) (CPAMAM) and then reduced in situ by NaBH4 to produce HEMNs with virtually a single-size distribution. The monitoring of the preparation process by UV-vis demonstrated the feasibility of this encapsulation approach, and the successful synthesis of three different types of HEMNs, Metal (Pd, Pt, Au)@CPAMAM, reflected the universality of this method. Compared with the existing catalyst octadecylamine-stabilized Pd nanoparticle—Pd@18N, HEMNs were superior in every aspect. The new encapsulation method allowed metal NPs to have a smaller particle size beneficial to its overall specific surface area and a higher proportion of active-surface atoms for a better catalytic activity. Moreove...