Propylene and propane separation method

Abstract

The invention discloses a propylene and propane separation method, which comprises the following step: an anion-containing hybrid supermicroporous material is used as an absorbent material to contactwith a propylene-propane gas mixture for identification and capture of propylene so as to realize separation of propylene and propane. The anion-containing hybrid supermicroporous material is formed by an inorganic fluorine-containing anion A, a metal ion M and an organic ligand L through a coordination bond, and the general formula is L-M-A. The organic ligand L is pyrazine and its derivative; the inorganic fluorine-containing anion A is any one of NbF7<2->, ZrF6<2->, GeF6<2->, SiF6<2-> and TiF6<2->; and the metal ion M is any one of Co<2+>, Ni<2+>, Fe<2+> and Mn<2+>. The pore diameter of theanion hybrid supermicroporous material is accurately regulated, which exhibits strong action force on propylene; and by controlling rotation degree of F atoms in the pores, propylene is allowed to enter the pore structure and the action force on propane is weak and the propane adsorbing capacity is less, thus realizing separation of propylene and propane.

Description

technical field [0001] The invention belongs to the technical field of chemical separation, and in particular relates to a method for the separation of propylene / propane by an anion hybrid ultramicroporous material. Background technique [0002] Propylene is one of the three basic raw materials for synthetic materials next to ethylene. As an important chemical basic raw material, it mainly comes from the by-products of catalytic cracking and steam cracking to produce ethylene. It is mainly used for the production of polypropylene, acrylonitrile, isopropanol, epoxy propane etc. In industrial production, the purity of propylene is crucial to the synthesis of high-quality polypropylene, so the removal of propane in the mixed gas is extremely important for the purification of propylene. At present, 41% of propylene consumption still needs to be met through imports; propane is often used as fuel for engines, etc., so propylene / propane separation is of great significance. [000...

AI Technical Summary

Problems solved by technology

[0004] In recent years, adsorption separation technology has attracted widespread attention. This process has small investment, simple operation, low production cost, and has good industrial application prospects. Its core is to develop high-capacity and high-selectivity adsorbent materials, but existing adsorbent materials often exist The incompatibility of high adsorption capacity and high selectivity greatly limits the application of adsorbent materials in the separation of propylene and propane

For example, metal organic framework material Cu-BTC has adsorption capacity of propylene propane of 7.7 and 7.1 mmol / g respectively, and the ratio of adsorption capacity is only 1.08, indicating that the separation selectivity is low (Micropor. Mesopor. Mat., 2012, 157, 101); Silicon-type molecular sieve DD3R has an ultra-microporous structure. At 318K, propylene is allowed to enter the pores, while propane is excluded from the pores, but the adsorption capacity for propylene is low (Micropor. Mesopor. Mat., 2008, 151, 585)

Therefore, it is still a big challenge to develop high-capacity and high-selectivity adsorbent materials to achieve efficient separation of propylene and propane.

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