PTMEG (polytetrahydrofuran ether glycol) is an important raw material for the production of chemicals and is widely used in polyurethane, elastomers, cellulose, polymers and other fields. The manufacturing method of PTMEG will be introduced below.
I. Raw material preparation
1. Tetrahydrofuran (THF): as the main raw material of PTMEG, tetrahydrofuran needs to be refined to remove water, impurities and so on.
2. Catalyst: Acidic catalysts, such as sulfuric acid and hydrochloric acid, are usually used.
2. Polymerization reaction
In the polymerization reactor, the refined tetrahydrofuran is mixed with catalyst and heated to a certain temperature to initiate the polymerization reaction. The polymerization reaction process needs to control the reaction temperature and pressure to keep the reaction proceeding smoothly. At the same time, the viscosity and molecular weight of the reaction solution need to be constantly monitored to determine the progress of the reaction.
III. Post-treatment
After the reaction is finished, post-treatment is required, including steps such as neutralization, dehydration, and refining, to remove impurities such as catalyst, unreacted tetrahydrofuran, etc., and to obtain a PTMEG product with high purity.
The specific manufacturing method is as follows:
1. Refining tetrahydrofuran: tetrahydrofuran is added to the refining kettle, heated to a certain temperature, and nitrogen is passed through to protect it and remove water and impurities.
2. Polymerization reaction: add refined tetrahydrofuran and catalyst into the polymerization reactor, heat to a certain temperature and start the polymerization reaction. Temperature and pressure need to be controlled during the reaction to keep the reaction going smoothly. At the same time, the viscosity and molecular weight of the reaction solution need to be constantly monitored to determine the progress of the reaction.
3. Neutralization post-treatment: After the reaction is finished, the reaction solution is transferred to the neutralization kettle, and an alkaline absorbent is added to neutralize the catalyst. Then dehydration treatment is carried out to remove residual water and unreacted tetrahydrofuran. Finally, refining treatment is carried out to obtain PTMEG products with high purity.
In the manufacturing process, the following matters need to be paid attention to:
1. Control the temperature and pressure of the polymerization reaction to avoid explosion, leakage and other safety accidents.
2. In the post-treatment process, ensure the purity and quality of the product to avoid problems such as impurities exceeding the standard.
3. Pay attention to environmental protection and energy saving and emission reduction during the manufacturing process to reduce the emission of waste and pollutants.
In short, the manufacturing method of PTMEG needs to go through several steps and links, and the reaction conditions and post-treatment process need to be strictly controlled to ensure the quality and purity of the product. At the same time, it is also necessary to pay attention to the requirements of environmental protection and energy saving and emission reduction to promote the sustainable development of the chemical production field.
