煤基高能量密度燃料的合成及表征

高能量密度燃料是为新型高性能飞行器提供动力保障的关键,其合成及应用研究具有重要的前瞻性和重大战略意义。煤炭是我国的主体能源和重要原料,通过煤直接转化获取的煤基油,充分保留了煤中特有的环状分子化学结构,具有良好的热安定性和较高的能量密度,被认为是高超音速飞行器的优选燃料。以煤直接液化工艺生产的煤液化石脑油馏分为起始原料,通过富集轻质芳烃、化学合成、催化加氢稳定和产物分离提纯等方法制备煤基高能量密度燃料,并对其产物进行分子结构表征和性能评价。结果表明,煤直接液化生产的石脑油馏分是一种优异的催化重整原料,经催化重整富集轻质芳烃后,其轻质芳烃质量分数高达71.05%。Diels-Alder化学合成主产物是由多个封闭环平面组成且具有空间立体构型的二环或三环烃类物质,质量分数为46.18%,因分子内存在较大的张力能,结构紧凑,其拥有更大的密度和体积热值。煤基高能量密度燃料的密度和体积热值分别为0.8990 g/cm3与38.06 MJ/L,均大大超过现行的国内石油基喷气燃料(RP-3和RP-6)、煤基大比重喷气燃料、美国和俄罗斯军用标准。与单一纯物质合成高能量密度燃料(JP-10和T-10)比较,其密度与体积热值偏小。究其原因主要是轻质芳烃的富集度仅为71.05%,需进一步提高其轻质芳烃质量分数。另外,制备的煤基高能量密度燃料种类复杂,其主产物质量分数仅46.18%,下一步可重点调控合成产物的分子构型和纯化分离。

Synthesis and characterization of coal-based high energy density fuel

High energy density fuel is the key to provide power support for new high performance aircraft,and its synthesis and application research has important prospective and strategic significance.Coal is the main energy source and important raw material in China.Coal-based oil obtained by direct conversion of coal fully retains the special ring molecular chemical structure of coal,has good thermal stability and high energy density,and is considered to be the preferred fuel for hypersonic aircraft.In this paper,a coal-based high energy density fuel was obtained by enriching light aromatics,Diels-Alder chemical synthesis,catalytic hydrogenation stabilization and product separation and purification from the naphtha fraction produced by direct coal liquefaction process.The molecular structure and properties of the product were characterized and evaluated.The experimental results show that the naphtha fraction by direct liquefaction of coal is an excellent catalytic reforming raw material.After catalytic reforming,light aromatics are enriched,and the content of aromatics is as high as 71.05%.The main products of Diels-Alder chemical synthesis have two-ring or three-ring configurations in closed space,and the content of which is about 46.18%,due to the large tension energy in molecules,the structure is compact,and it has a larger density and calorific value of volume.The density and volumetric calorific value of synthesized coal-based high energy density fuel is 0.8990 g/cm3 and 38.06 MJ/L respectively,which greatly exceeds the current domestic petroleum-based jet fuel(RP-3 and RP-6),coal-based jet fuel,and the US and Russian military standards.However,compared with synthesized high energy density fuels(JP-10 and T-10)from a single pure substance,it is still relatively small.The main reason is that the enrichment of light aromatics is only 71.05%,which can further improve the content of light aromatics.In addition,the types of coal-based high energy density fuels are complex,and the content of main products is 46.18%.The next step is to adjust the molecular configuration and purification of the synthesized products.