Pyrolysis behavior of supercritical n-decane over nano nickel oxide modified commercial HZSM-5

Endothermic pyrolysis process of hydrocarbon fuel has great potential in the cooling usages. But the issues of unsatisfied heat sink and severe coking limit the further development. We made the nano NiO hybrid thin layers wrap on the commercial HZSM-5 (denoted as ZSM-5@NiO) by incipient-wetness impregnation method, and got the significant modulation ability for the acidity properties of HZSM-5. The experimental results shows that the as-prepared catalysts can improve the heat sink of supercritical cracking of n-decane from 3.8 MJ/kg at 728 ^oC to 4.6 MJ/kg at 780 ^oC, and higher than the HZSM-5 for 3MJ/kg at 687 ^oC as a comparison catalyst, here the temperature is the highest temperature at the moment when the experiment pipe was block by coke. It is also found that ZSM-5@NiO generated more gas products which was positively correlating with the heat sink. The synergistic effect between NiO and HZSM-5 dramatically lowers the overall acidity of composite and results in effective anti-coking properties. Present work demonstrates that the introduction of nanostructured metal oxides into HZSM-5 will synergistically adjust the acidity of composite, finally providing deep insights for the design and fabrication of catalysts for hydrocarbon fuel cracking.