Method for producing ethylene-propylene copolymer by recycling ethylene and hydrogen in catalytic dry gas in refinery

Abstract

The invention belongs to the field of production of ethylene propylene copolymers and relates to a method for producing an ethylene-propylene copolymer by recycling ethylene and hydrogen in catalytic dry gas in a refinery. The method for producing the ethylene-propylene copolymer by recycling the ethylene and the hydrogen in the catalytic dry gas in the refinery comprises the following steps of: extracting ethylene and hydrogen from the catalytic dry gas by using a pressure swing adsorption technology, wherein the purity of obtained ethylene is more than or equal to 85 percent, and the purity of hydrogen is more than or equal to 99 percent; and producing the ethylene-propylene copolymer by using propylene, a catalyst, an aid and extracted ethylene and hydrogen as raw materials. According to the invention, the catalytic dry gas in the refinery is effectively recycled, and application of the propylene polymer in the refinery is enlarged simultaneously. By adopting the method, only a small amount of devices are added, ethylene and hydrogen are not required to be purchased, and the ethylene-propylene copolymer with different properties can be produced; and the method is simple in whole operation process, low in production cost and suitable for industrialized production.

Description

technical field [0001] The invention belongs to the field of ethylene-propylene copolymer production, and in particular relates to a method for producing ethylene-propylene copolymer by recycling ethylene and hydrogen in catalytic dry gas of a refinery. Background technique [0002] Polypropylene (PP) is a kind of general-purpose plastic widely used. Its raw materials are rich in sources, and its products have excellent mechanical properties and chemical corrosion resistance. However, at present, most domestic refineries have polypropylene production workshops, and the supply of polypropylene exceeds demand. In addition, pure PP has disadvantages such as poor low-temperature performance and strong notch sensitivity, which greatly limit its application range. [0003] Adding ethylene monomer in the propylene polymerization process can produce ethylene-propylene copolymers with a wide range of uses; for example, ethylene-propylene copolymers with an ethylene content of 2 to 4...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to provide a method for recycling ethylene and hydrogen in the catalytic dry gas of a refinery to produce ethylene-propylene copolymers; the method not only effectively recycles ethylene and hydrogen in the catalytic dry gas, but also effectively solves the problem of Current Situation of Overproduction of Polypropylene in Refinery