采用NaOH溶液对含有模板剂氢氧化四乙基铵(TEAOH)的 Hβ沸石进行脱硅处理，制备了介孔 Hβ沸石；采用过量液相浸渍法制备了一系列介孔 Hβ沸石负载磷钨酸(PW)催化剂，考察了其在桥式四氢双环戊二烯(endo-TCD)异构化制备金刚烷反应中的催化性能；并采用 XRD、液 N2吸附和 NH3-TPD 对催化剂的物化性质进行了表征。表征结果表明，当 PW 酸负载量达到30%时，其仍能在介孔Hβ沸石表面高度分散，且对应的催化剂的酸量最大。采用30%PW/介孔 Hβ沸石为催化剂，在反应温度240℃，w(catalyst)/w(endo-TCD)=0.6，反应时间为5 h 时，endo-TCD的转化率达到99.4%；与 PW/Hβ沸石相比，PW/介孔 Hβ沸石由于其存在部分介孔，金刚烷的收率提高至原来的1.46倍，原来的22.4%提高至32.7%；且催化剂再生能力良好，重复使用6次后，金刚烷收率还高达28.7%。%Desilicated mesoporous Hβ zeolite was prepared through treating Hβ zeolite including template tetraethylammonium hydroxide (TEAOH) with NaOH aqueous solution. 12-Tungstophosphoric acid (PW) was immobilized on the desilicated mesoporous Hβzeolite at room temperature to form the PW/meso-Hβcatalysts. The physical and chemical properties of the PW/meso-Hβ catalysts were characterized by X-ray diffraction (XRD), liquid N2 adsorption-desorption and temperature programmed desorption of ammonia (NH3-TPD), respectively; and the catalytic performances of the prepared PW/meso-Hβ catalysts were investigated by catalyzing the isomerization reaction of endo-tetrahydrodicyclotadiene (endo-TCD) to form adamantane (ADH) in a 100 mL batch stainless-steel autoclave with stirring. The results show that the loaded PW could still be highly dispersed on the surface of the desilicated mesoporous Hβzeolite when the PW loading is 30%, and the 30%PW/meso-Hβcatalyst has the largest acid amount. When using 30%PW/meso-Hβzeolite as catalyst, 99.4%conversion of endo-TCD can be obtained under the following conditions: reaction temperature of 240℃, the catalyst to endo-TCD mass ratio of 0.6 and reaction time of 5 h. In comparison with PW/Hβcatalyst, the yield of ADH increases from 22.4%to 32.7%because of the presence of mesopores in the desilicated Hβzeolite. The catalytic activity of used catalyst can be recovered and the yield of ADH can still reach 28.7%after 6 times reuse.
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