PTW (dimethyl terephthalate) is an important raw material for the production of chemicals, widely used in plastics, fibers, coatings and other fields. The following is the manufacturing method of PTW:
I. Raw Material Preparation
The main raw materials for manufacturing PTW are terephthalic acid (PTA) and methanol (MeOH). Before starting the production, it is necessary to ensure that the quality and purity of raw materials meet the requirements, as well as to check and clean the equipment to ensure the smooth running of the production process.
II. Esterification Reaction
PTA and MeOH are added to the esterification reactor according to a certain molar ratio, usually in a continuously stirred kettle reactor (CSTR). Under high temperature, high pressure and catalyst, PTA and MeOH undergo esterification reaction to produce PTW and water. Temperature and pressure need to be controlled during the reaction to ensure the smooth progress of the reaction.
Third, catalyst removal
After the reaction is finished, the catalyst needs to be removed from the reaction system to avoid the influence on the subsequent processes. Alkaline absorbent is usually used to neutralize the catalyst to precipitate it from the reaction system.
Four, distillation separation
After the catalyst is removed, the reaction solution needs to be distilled and separated to obtain a higher purity PTW product. Usually a multi-tower distillation process is used to first separate the water and then separate the PTW from the methanol. The tower temperature and reflux ratio need to be controlled during the separation process to obtain the best product quality and yield.
V. Product quality testing and packaging
The separated PTW products need to be tested for quality, including purity, color, acid value and other indicators. After passing the test, it will be packed and put into storage to complete the whole manufacturing process.
The above is the manufacturing method of PTW, the specific production process needs to be adjusted and optimized according to the actual situation to ensure product quality and production efficiency. At the same time, the production process needs to pay attention to safety and environmental protection, and comply with relevant laws and regulations and standard requirements.
