Method for reducing waste acid amount in cation resin production process by adopting gradient dilution method

Abstract

The invention discloses a method for reducing the waste acid amount in a cation resin production process by adopting a gradient dilution method. The method comprises the following steps: in a cation exchange resin manufacturing process, feeding gel type or macroreticular white balls into a sulfonation reaction kettle for sulfonation reaction; adding sulfuric acid at the concentration of 92 percent, which is prepared from concentrated sulfuric acid at the concentration of 105 percent and recycled directly discharged mother liquor acid or dilute sulfuric acid liquid at the concentration of 60 to70 percent, and performing reaction by taking the sulfuric acid as sulfonation reaction acid; after the sulfonation is completed, performing gradient dilution and resin cleaning, thus obtaining a cation resin product. According to the method disclosed by the invention, mother liquor and diluted acid are supplementarily added into the concentrated sulfuric acid at the concentration of 105 percentto prepare the sulfuric acid at the concentration of 92 percent, which is used as the sulfonation reaction acid, and acid dilution is performed by adopting a gradient dilution application method, so that the concentration of the diluted acid can be concentrated at 70 percent or above; the diluted acid can be cyclically reused to prepare cation resin or reaches a concentration range used in other fields, so that the aims of saving resources and reducing waste acid discharging are fulfilled.

Description

technical field [0001] The invention belongs to the field of fine chemical polymer resin synthetic materials, in particular to a method for reducing the amount of waste acid in the production process of cation resin by adopting a gradient dilution method. Background technique [0002] Ion exchange resin has developed rapidly since the 1960s. Because it is a kind of polymer material that can display ion exchange function, and its application technology development has been mutually promoting and interdependent, it has become the first choice of functional separation materials in various fields. The preferred and essential material is in increasing demand. With the rapid development of China's economy, my country has now become the largest producer of ion exchange resins in the world, of which the production of cation exchange resins accounts for a large proportion. The ion exchange resin is composed of so-called fixed ions that are chemically bonded to many exchange groups o...

AI Technical Summary

Problems solved by technology

Most of the acid is washed with water to wash the resin after sulfonation reaction. It is necessary to overcome and prevent the high dilution heat produced by the meeting of water and sulfuric acid, which will cause the fragmentation of the polymer beads and the impact on the strength. It must be gradually and slowly diluted with water to dissolve the polymer. The inside and outside of the beads and the concentration of sulfuric acid are replaced and washed out in a balanced manner, thus producing a large number of dilute acids of different concentrations, and these dilute acids can no longer be directly used in the sulfonation reaction due to the decrease in concentration, but can only be neutralized and discharged. Therefore, not only It causes a large waste of resources, and makes wastewater treatment very troublesome, and even affects normal production and operation. How to make comprehensive utilization of waste acid and reduce waste is an important issue that must be properly solved in this process.

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