Hydrogenation method for olefin unsaturated bond-containing polymer

Abstract

The invention discloses a continuous hydrogenation method for olefin unsaturated bond-containing polymer. The method comprises a step of contacting a solution of the olefin unsaturated bond-containing polymer with hydrogen for hydrogenation in the presence of a hydrogenation catalyst, wherein a hydrogenation reactor used comprises two or more than two serially connected reactors; in the hydrogenation process, reaction effluent of a first reactor is divided into two parts, one part enters a second reactor, and the other part exchanges heat with a heat exchanger and is recycled to return the first reactor; by controlling the apparent velocity of hydrogen bubbles flowing through a reaction mixture and the circulating flow of the reaction effluent, the first reactor approaches full-Francis operation, and the second and subsequent reactors approach piston flow operation; and the reaction mixture is continuously hydrogenated through hydrogen dissolved in the reaction mixture by maintaining the hydrogen pressure in the reactor. By the method, the hydrogen and the polymer solution are fully contacted uniformly, so the hydrogenation efficiency is improved; and the temperature in the hydrogenation process can be stably controlled, so the catalyst is prevented from being deactivated due to high temperature; therefore, products with an ideal hydrogenation degree are stably obtained in a long operating period. Meanwhile, material consumption, energy consumption and operating cost in the reaction process are reduced.

Description

technical field [0001] The invention relates to a continuous hydrogenation method for polymers containing olefinic unsaturated bonds. The method comprises making the solution of polymers containing olefinic unsaturated bonds contact with hydrogen for hydrogenation in the presence of a hydrogenation catalyst. Background technique [0002] In order to improve the heat resistance, oxygen stability and aging resistance of polymers containing olefinic unsaturated bonds, hydrogenation is usually used to saturate the olefinic unsaturated bonds of the polymers. It is generally required that the degree of unsaturation of the polymer after hydrogenation is less than 2% (ie, the degree of hydrogenation is greater than 98%) to achieve significant performance improvements. [0003] U.S. Patent No. 6,815,509B2 discloses a polymer hydrogenation method, which includes contacting a polymer containing olefinic unsaturated groups with hydrogen in the presence of a hydrogenation catalyst to mak...

AI Technical Summary

Problems solved by technology

The disadvantage of this patent is that the reactor structure is complex, the manufacturing cost is high and the hydrogenation degree of the final product is low

[0007] In the prior art, U.S. Patents US 4,501,875, US 4,673,714 and British Patent GB2,159,819A all use stirred tanks for intermittent hydrogenation. Due to the high concentration of double bonds in the reaction solution in the early stage of the reaction and the fast hydrogenation rate, the heat release is large, making the reaction The temperature is difficult to control, which will deactivate part of the catalyst and affect the hydrogenation efficiency

In addition, the batch reaction is not conducive to industrial scale-up

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