高密度烃燃料四氢环戊二烯三聚体的合成及热裂解

Synthesis and Thermal Decomposition of Tetrahydrotricyclopentadiene as a High Density Hydrocarbon Fuel

以双环戊二烯为原料,经D-A反应及催化加氢合成了高密度烃燃料四氢环戊二烯三聚体（ THTCPD）.该三聚体的密度为1.082 g/cm3,体积热值为47.5 MJ/L,闪点为120℃,凝固点为48-49℃.采用裂解器与色谱-质谱联用技术,对THTCPD的热裂解进行了在线监测,结果表明温度对裂解反应影响较大.对裂解产物的结构进行了分析,产物以甲烷、乙烯、丙烯、环戊烯、环戊二烯、苯和甲苯为主.依据产物结构及单分子自由基反应模型,推测得到了9种路径的裂解机理.采用X3LYP法进行了各自由基的热力学计算,得到各反应路径的相对能量及路径比.通过不同温度下的裂解转化率,计算得到热裂解反应动力学方程,经线性拟合得到活化能Ea=6.67×104 kJ/mol,指前因子A=133.75.

As a high density hydrocarbon fuel, tetrahydrotricyclopentadiene（ THTCPD） was synthesized from dicyclopentadiene and indene by D-A reaction and hydrogenation. The density of THTCPD is 1.082 g/cm3 , volumetric combustion heat is 47.5 MJ/L, flash point is 120 ℃ and freezing point is 48-49 ℃. Thermal de-composition of THTCPD was studied in a decomposition reactor at atmospheric pressure, in the temperature range of 973-1153 K. Products were detected by gas chromatography-mass spectroscopy. The major products were methane, ethylene, propylene, cyclopentene, cyclopentadiene, benzene and toluene. The conversion of THTCPD at different temperatures and time was investigated. The results indicated that the effect of tempera-ture was superior to other factors in this reaction. A primary mechanism including nine pathways was also pre-sumed according to the main products of the reaction and the monoradical mechanism. Density functional theo-ry calculations （ X3 LYP ） of the potential energy surface was performed to investigate the mechanisms of THTCPD breakdown. Relative energy and ratio of reation routes were computed. The kinetic equation of ther-mal decomposition was obtained by relation of the conversion and temperature. The pre-exponential factor and activation energy overall reaction order for thermal cracking of THTCPD were determined by linear regression analysis to be 133.75 and 6.67×104 kJ/mol, respectively.