氧化铬催化剂催化氟化1,1,1-三氟2-氯乙烷性能研究  

Performance Study on 1,1,1-Trifluoro-2-Chloro Ethane Catalytic Fluorination over Chromium Oxide Catalysts

作　　者：梁艳[1] 张文霞[1] 王芳[1] 王月娟[1] 罗孟飞[1] 

机构地区：[1]浙江师范大学物理化学研究所,浙江金华321004

出　　处：《化工生产与技术》2016年第1期1-3,6,共3页Chemical Production and Technology

基　　金：国家自然科学基金(21373186)

摘　　要：采用沉淀法制备了晶相Cr_2O_3催化剂,用浸渍法在晶相Cr_2O_3载体上负载无定型Cr_2O_3(所得催化剂以α-Cr_2O_3/Cr_2O_3表示),并考察了2个催化剂对1-氯-2,2,2-三氟乙烷(HCFC-133a)制备1,1,1,2-四氟乙烷(HFC-134a)的氟氯交换反应性能的不同影响。结果表明,Cr_2O_3催化剂的活性较低但却很稳定,α-Cr_2O_3/Cr_2O_3由于少量高价铬的引入,使得起始活性高于Cr_2O_3催化剂。H2-TPR分析表明,α-Cr_2O_3/Cr_2O_3催化剂中高价态Cr含量明显高于Cr_2O_3催化剂。高价铬在反应过程中容易流失,导致α-Cr_2O_3/Cr_2O_3催化剂催化活性下降。结合XRD和反应活性可以发现,α-Cr_2O_3比晶相Cr_2O_3有着更高的催化活性。Crystalline Cr_2O_3 catalyst was prepared by precipitation method, and amorphous Cr_2O_3 loaded in crystalline Cr_2O_3 supporter by impregnated method(obtained catalyst designated as α-Cr_2O_3/Cr_2O_3). Both of the Cr_2O_3 and α-Cr_2O_3/Cr_2O_3 catalysts were tested for the different effect on F/Cl exchange reaction performance of 1-cholo-2,2,2-trifluoroethane(HCFC-133a) to 1,1,1,2-tetrafluoroethane.The results showed that the activity of the crystalline Cr_2O_3 catalyst was low but very stable during the reaction. On the contrary, theα-Cr_2O_3/Cr_2O_3 catalyst had higher initial activity due to the introduction of a small amount of high-valent Cr species. The H2-TPR proles showed that the α-Cr_2O_3/Cr_2O_3 catalyst contained higher content of high-valent Cr species compared to the Cr_2O_3 catalyst. Such high-valent Cr species could be easily depleted during the reaction, which accounted for the catalyst deactivation. Combined with XRD and catalytic behaviours of the Cr_2O_3 and α-Cr_2O_3/Cr_2O_3 catalysts, it was concluded that the α-Cr_2O_3 species had higher catalytic activity than the crystalline Cr_2O_3 species.

关 键 词：催化剂 CR2O3 α-Cr2O3/Cr2O3 氟-氯交换反应 

分 类 号：O621.251[理学—有机化学]