摘要
采用共混法制得Cr-Mg-Zn催化剂,以HCFC-133a(1,1,1-三氟-2-氯乙烷)与无水HF合成HFC-134a(1,1,1,2-四氟乙烷)为目标反应,考察了不同条件下该催化剂的性能。用BET法表征了催化剂的比表面积、孔容、孔径,并对催化剂进行XRD、TG-DSC表征。结果表明,在AHF/HCFC-133a摩尔比为7和300℃条件下转化率为25.4%,选择性为95.7%,连续反应90天后活性下降到原来的80%;在O2中再生,发现转化率比再生前提高,可能是由于再生过程中氟化物产生水解生成了氟氧化物,而该类物质为本反应的活性物质。
The performance of the Cr - Mg - Zn catalyst which is prepared by mechanical mixing for synthesis of 1, 1,1,2 - tetrafluoroethane（ HFC - 134a） from reaction of 1,1,1 - trifluoro - 2 - choroethane （ HCFC - 133a） with AHF is investigated. BET,TG -DSC and XRD have been employed to characterize the catalyst. When temperature is 300℃ and mole ratio of AHF is 7 ,the HCFC - 133a conversion of HCFC - 133a and the selectivity of HFC -134a are 25.4% and 95.7% ,respectively. The original catalytic activity cut to 80% after 90 days recation. We regenerate it in O2 and find that it shows higher activity than before. It can be explained that during the regeneration the metal fluorides hydrolyze and form metal oxyfluoride which is the active species of the recation.
出处
《有机氟工业》
CAS
2007年第1期5-8,共4页
Organo-Fluorine Industry
