Molecular structural characterization and performance evaluation of coal-based high energy density liquid fuel based on chemical synthesis

LI Junfang

doi:10.3969/j.issn.1007-7677.2025.06.004

Abstract：As a key energy carrier of aerospace,military equipment and high performance power system,the devel-opment of high energy density liquid fuel has important strategic significance.In this study,aiming at the unique cyclic molecular structure and high calorific value characteristics of light aromatic hydrocarbons(toluene as a mod-el compound)in coal-based oil,a two-step synthesis process was adopted.Firstly,the addition reaction of toluene and norbornene was catalyzed by MCM-22 molecular sieve to generate high energy density fuel intermediates,and then the Ru/C catalytic hydrogenation stabilization treatment was carried out to obtain high energy density fuel.The reaction process was systematically investigated by multi-scale characterization methods.The molecular structure evolution of the product before and after hydrogenation was analyzed by GC-MS,FT-IR and NMR techniques.The structure-activity relationship of MCM-22 molecular sieve catalyst was revealed by means of SEM,BET and NH3-TPD.The experimental results show that the addition reaction of toluene and norbornene exhibits excellent catalytic performance(conversion rate>99％,selectivity 93.55％)under the regulation of acidic sites of MCM-22 molecular sieve.A high-energy fuel intermediate with rigid spatial configuration was successfully constructed.After the Ru/C catalyst hydrogenation stabilization treatment,the density of the product reached 0.954 9 g/cm3,and the volume energy density was as high as 44.66 MJ/L,which was significantly improved,compared with the traditional petroleum-based jet fuel,fully demonstrated the performance advantages of coal-based fuel.The mechanitic study shows that the conversion process cleverly combines the high density characteristics of the aromatic ring and the ring strain energy storage advantages of norbornene,and achieves efficient conversion from coal-based aromatics to high-energy fuels through the synergistic strategy of"molecular sieve catalytic addition-noble metal hydrogenation stability".This study not only provides a new idea for the high-value utilization of coal resources,but also establishes a method-ological basis for the molecular design of special fuels.Future research will focus on breaking through three major engineering problems:Using real coal-based oil system to optimize raw material suitability,developing inhibitors to control norbornene self-polymerization,modifying catalysts to improve life,and realizing industrialization through continuous flow process to meet the demand for high-performance fuels in the aerospace field.