| Some separation processes based chemical action could bring higher selectivity, separation efficiency and transfer rate. Because of these characteristics, this method was becoming the one of important ways to improve the traditional separation techniques with high energy consumed.The separation process of ethylene and ethane by traditional rectification at low temperature consumed a great deal of energy. Adsorption separation via complexation was a method which combined both -complexation reaction and the process of adsorption. This method could be used on the process of ethylene and ethane's separation because of the potential superiority of economizes on energy, and this would focus on development of complexation adsorbent. In this paper, current situation of adsorption separation via complexation in industry application and complexation adsorbent research were summarized. At the same time, adsorption mechanism and preparation of new adsorbents with high adsorption selectivity of ethylene were studied respectively, so did both adsorption equilibrium of the prepared sorbent and behavior of adsorption on fixed bed. All of these studies established a solid foundation of application in industry scale that the new process of ethylene and ethane's separation had lower economizes on energy.Both carbon monoxide and ethylene could form complexation with some transition metal cations such as Cu+ and Ag+. Separation via complexation of CO had already been used in industry scale, but there had no report about that of ethylene as yet. On the basis of the differences between carbon monoxide and ethylene in their adsorption behaviors, the molecular configurations of the complex compounds were studied by using calculation tool of quantum chemistry combined with the theory of molecular orbit. In addition, carbon monoxide, ethylene and propylene could react with copper chloride and silver chloride respectively, and from study of these reactions, it could be concluded that the order of complexation abilities was: CO>C2H4>C3H6, and to the same ligand, CuCl > AgCl. Moreover, the structure of the complex of CO and CuCl was linear, and that of alkenes and AgCl was planar three-member ring. These results could offer theoretical guidance to preparation of complexation adsorbent.Through comparing the different characteristics of adsorption via complexation and the separation systems of carbon monoxide and ethylene, it had been put forward that surface qualities of active carbon carrier could be modified by oxidation during the course of preparation. At the same time the microcosmic characteristics of active carbon modified by load of CuCl had also been studied. Besides of that, monolayerdissipation of CuCl on the surface of active carbon was characterized by BET, XRD and TEM. Preparation techniques of CuCl-loaded active carbon adsorbent were also discussed and new complexation adsorbent for ethylene/ethane separation was obtained. Compared to the ethylene complexation adsorbent, which reported on other documents, CuCl-loaded active carbon adsorbent had higher ethylene selectivity, smaller adsorption heat and more stable regenesis of pressure swing. Therefore, it had better industry application foreground.Adsorption equilibrium data of ethylene, ethane and their mixture had been determined after the preparation of complexation adsorbent. An adsorption equilibrium model with physical adsorption and chemical adsorption was established respectively, which according the mechanism of complexation adsorption. Physical meanings of the model parameters were authentic. The adsorption equilibrium of binary mixture on complexation adsorbent could be predicted from the mono component pattern. Thus, necessary data of industry application and design-foundation of the complex adsorbent had been obtained.The adsorption dynamic performance of ethylene, ethane and their binary mixture on complexation adsorbent had been studied. The effects of concentration, temperature, pressure and flow rate on breakthrough curve were compared. T... |
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