Large-scale reactive molecular dynamics research on pyrolysis mechanics of spiro[4.5]decane

Spiro-fuels, as the derivative of cyclic ketones obtained from lignocellulose, are promising alternative biofuels. In this work, the overall pyrolysis mechanism of spiro[4.5]decane, the most representative spiro-fuel, is revealed by large-scale reactive molecular dynamic simulations. The pyrolysis of spiro[4.5]decane can be divided into three stages: the decomposition of spiro[4.5]decane begins with the ring-opening in one of the two rings, leading to four representative alicyclic intermediates firstly. Then these intermediates further decompose and form a series of small molecular products through allyl radicals. Finally, the generated products further react and gradually form soot precursors. It is also found that the reaction temperature affects the initial pathways and intermediate distributions, and ultimately change the product distributions. In addition, the apparent activation energy of spiro[4.5]decane pyrolysis is also calculated, and the result (259 kJ/mol) suggests an activity close to JP-10.