Preliminary Exploration For Adsorption Separation Of HFP And HFPO

Hexafluoropropylene oxide(HFPO) is a very important epoxide which containsfluorine, and it is the intermediate for the production of organic fluorine chemicals.There are many methods to prepare HFPO which use hexafluoropropylene(HFP) asraw material at domestic and overseas. Since the conversion rate of the reaction cannot achieve100%, the HFPO product must contain unreacted raw material. In orderto obtain high purity HFPO in industry, it’s need to purify the products. Now themethods for purifying HFPO mainly include the method of bromination, directdistillation, extraction distillation and so on. In these methods, the problems of theextraction distillation method are that it needs a long time for the separation process,the large of the solvent and energy consumption. Compared with the above methods,adsorption separation method is a better method. There are no reports about theadsorption of HFP and HFPO, so we conducted a preliminary exploration foradsorption method to separate HFP and HFPO mixture.We carried on the preliminary filtrating by the dynamic penetration experimentfor the adsorbents after consulting massive of literature. We can knew that thehigh-temperature clay and activated alumina have a certain separation efficiency forthe mixture from the results. We found that the adsorbents from differentmanufacturers or batches also have an important influence on the performance ofadsorption separation during the experiments. The8#high-temperature clay and9101#activated alumina were analyzed and characterized in the experiments, and atthe same time we investigated the breakthrough curves in different experimentalconditions. In order to improve the adsorption activity of the adsorbents, wemodified them by impregnation method.We determined the dynamic and static adsorption performance of HFP andHFPO by the before and after modification of8#high-temperature clay and9101#activated alumina. In order to calculate the dynamic separation coefficient of theadsorbents we determined the dynamic breakthrough curves of HFP and HFPO, and the outcomes are: the dynamic separation coefficients of8#high-temperature clayand9101#activated alumina are1.8and2.7respectively, and they’re2.3and3.1respectively after modification, and we used the vacuum gravimetric adsorptiondevice to determine the adsorption isotherms of HFP and HFPO by the adsorbents atdifferent temperature, and calculate the adsorption capacity. Eventually we filtratedout the adsorption separation agents which have clear separation effects.