A method for preparing polycarboxylate superplasticizer macromonomer by using waste lithium battery

Abstract

The invention discloses a method for preparing a polycarboxylate superplasticizer macromonomer by using a waste lithium battery, namely, a preparation and synthesis method of allyl polyethylene glycol monomethyl ether. The method is characterized by comprising the steps of making polyethylene glycol monomethyl ether react with chloropropene at a temperature of 60 DEG C for 4-5 hours under the conditions that metal lithium extracted from the recovered waste lithium battery is used as a catalyst, tetrabutylammonium hydrogen sulfate is used as a phase transfer catalyst and an atmosphere is protected by an inert gas, and continuously cooling at a temperature of 50 DEG C for 1 hour to discharge the polycarboxylate superplasticizer macromonomer. According to the method, lithium in the recovered waste lithium battery is used as the catalyst, so that the resource is favorably recycled. Compared with a conventional direct esterification method, the method has the advantages that the reaction can be performed at a relatively low temperature of 50-60 DEG C and a normal pressure, the requirement for equipment is relatively low, the retention rate of generated double bonds is high, and the generated allyl ether bonds are more stable than allyl ester bonds and are difficult to hydrolyze. The method is relatively high in reaction conversion rate, free from waste emission in a preparation process, and low in production cost.

Description

technical field [0001] The invention belongs to the field of cement additives, in particular to a method for preparing and synthesizing polycarboxylate superplasticizer macromonomers. Background technique [0002] In recent years, the research and production of concrete admixtures have tended to develop in the direction of high performance and pollution-free. Concrete water reducer is the most widely used and most widely used concrete admixture. The polycarboxylate high-efficiency water reducer with a comb-shaped molecular structure is suitable for the preparation of high-strength and ultra-high-strength concrete because of its high water-reducing rate, good slump retention performance, low dosage, no pollution, less retarding time, and low cost. , high fluidity and self-compacting concrete has become a hot spot in the research and development of concrete admixtures at home and abroad. [0003] The water reducing agent mixed into fresh concrete can destroy the flocculation...

AI Technical Summary

Problems solved by technology

The use of other catalysts such as sodium hydroxide does not reduce the discharge of garbage (such as waste lithium batteries), does not play a role in improving the recycling rate of resources and protecting the environment, and the use of water-carrying agents also has certain defects. , first increases the cost, and secondly, the use of water-carrying agent needs to use moisture device and reflux device, and the reaction also needs vacuum distillation to remove solvent, the process is complicated, the requirements for equipment are high, and the processing cost is high

Finally, the water-carrying agent itself has certain toxicity, which is not conducive to environmental protection

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