Enhanced cracking conversion of supercritical fuel over stabilized Pt nanoparticles supported SiO2-Al2O3 catalyst coating

Catalytic cracking of fuel is an effective method to solve the thermal barrier of hypersonic aerocraft, but requires catalysts that are durable and highly active under high temperature. In this contribution, Pt nanoparticles loaded SiO2-Al2O3 catalyst (PSA-re) was synthesized through modified colloid deposition method (CDM), aiming to improve the stability and dispersion of Pt in the reaction. PSA-re exhibited high cracking activity that heat sink of above 3.9 MJ/kg at 750 degrees C and stand for 30 min without obvious activity decreasing. Characterizations with PyFTIR, H2-TPR, CO chemisorption, XPS, XRD, STEM and CO-DRIFTS techniques on the catalysts revealed that the Pt nanoparticles were dispersed on the PSA-re uniformly and PSA-re have smaller particle size as well as higher Pt dispersion compared with catalyst (PSA-im) that prepared by incipient wetness impregnation method (IWIM). The high activity of PSA-re is strongly associated with abundant accessible Pt metal sites and appropriate acid sites distribution on the surface. Meantime, the outstanding stability is mainly due to anti-sintering ability of Pt particles and alleviated carbon deposition to reduce the loss of Pt metal sites and acid sites.