镁-铝氟化物催化剂的制备及其催化1,1,1,3,3-五氟丙烷气相脱氟化氢反应性能的研究

Preparation of magnesium-aluminum fluoride catalyst and its catalytic performance in gas-phase dehydrofluorination of 1,1,1,3,3-pentafluoropropane

利用多元醇氟化法制备了氟化铝、氟化镁及镁铝复合型氟化物等催化剂,并对所制催化剂在1,1,1,3,3-五氟丙烷(HFC-245fa)气相脱氟化氢制备1,3,3,3-四氟丙烯(HFO-1234ze)反应中的催化性能进行了研究。结果表明,单一氟化镁催化剂活性较低,HFC-245fa转化率仅为7.8%;以摩尔分数为9%Al/MgF_2作为催化HFC-245fa脱氟化氢反应催化剂,在反应温度为280℃,接触时间为25 s,催化剂用量为5 m L时,HFC-245fa的转化率、HFO-1234ze的选择性分别达到53%和100%,与单一组分氟化铝催化性能相当,且运行200 h后保持96%的初始活性。

Gas-phase catalytic dehydrofluorination of 1,1,1,3,3-pentafluoropropane（ HFC-245 fa） to prepare 1,3,3,3-tetrafluoropropylene（ HFO-1234 ze） is investigated over a series of magnesium fluoride,aluminum fluoride and magnesium-aluminum fluoride catalysts that are prepared by polyols mediated fluorination method. The results show that the conversion of HFC-245 fa is only 7. 9% over single magnesium fluoride catalyst. Higher conversion of HFC-245 fa（ 53%） and higher selectivity of HFO-1234 ze（ 100%） are achieved over 9 mol. % Al/MgF2 catalyst when the dosage of catalyst is 5 m L,the reaction temperature is 280℃ and the contact time is 25 s. The catalytic performance is same as single aluminum fluoride catalyst.The catalyst can still retain 96% of initial activity after it has been used for 200 hours.