SiW/Hβ催化剂用于挂式四氢双环戊二烯的制备

Exo-tetrahydrodicyclopentadiene (exo-TCD) is an important high-energy fuel.Silicotungstic acid (SiW) immobilized on H-type β zeolite (Hβ) at room temperature were used to prepare the Hβ zeolite catalysts with different SiW contents.Catalytic performances of the catalysts were investigated during the preparation of exo-TCD via isomerization of endo-tetrahydrodicyclopentadiene (endo-TCD).The properties of catalysts were characterized by XRD,temperature pro-grammed desorption of ammonia (NH 3-TPD),FT-IR,and N 2-adsorption techniques.SiW was highly dispersed on the surface of Hβ zeolite,and the 10% SiW/Hβ zeolite catalyst had the highest amount of weak acidity among all SiW/Hβ zeolite catalysts.The influence of different factors on isomerization reaction was investigated.At a reaction temperature of 240 ℃,a n(cyclohexane) /n(endo-TCD) ratio of 10,a m(catalyst) /m(endo-TCD) ratio of 0.3,an initial pressure of 1.0 MPa,and a reaction time of 1.5 h in the presence of 10% SiW/Hβ catalyst calcined at 400 ℃,the conversion of endo-TCD reached up to 92.0%,with the yield of exo-TCD equating to 51.0%.