Pentaerythritol (PE for short) is an important raw material for the production of chemicals, widely used in coatings, plastics, adhesives, explosives, fuels and other fields. The following are the manufacturing methods of Pentaerythritol:
I. Acetaldehyde Method
Acetaldehyde method is the main method to produce Pentaerythritol, and its raw materials are acetaldehyde and formaldehyde. The specific steps are as follows:
1. Mix acetaldehyde and formaldehyde at a molar ratio of 1:3, add an acidic catalyst, and react at 70-90°C for 2-3 hours to produce 3-hydroxymethylbutyraldehyde.
2. 3-Hydroxymethylbutyraldehyde was reacted with an excess of formaldehyde in the presence of an alkaline catalyst for 2-3 hours at 70-90°C to form pentaerythritol.
3. Neutralize the reaction solution with an acidic solution, remove the catalyst, and then distill to obtain a higher purity of pentaerythritol.
II. Glyoxal method
Glyoxal method is a method to produce pentaerythritol by addition reaction and condensation reaction using glyoxal and formaldehyde as raw materials. The specific steps are as follows:
1. Mix glyoxal and formaldehyde at the molar ratio of 1:2, add acid catalyst, and react at 70-90℃ for 2-3 hours to produce 3-hydroxymethylpropionaldehyde.
2. 3-Hydroxymethylpropionaldehyde was reacted with an excess of formaldehyde in the presence of an alkaline catalyst for 2-3 hours at 70-90°C to form pentaerythritol.
3. The post-processing steps are the same as those of the acetaldehyde method, and the pentaerythritol of high purity can be obtained after neutralization and distillation.
3. Biological method
The biological method is a method of producing pentaerythritol using microbial fermentation. The specific steps are as follows:
1. Add glucose, yeast leachate and other nutrients into the fermenter, and inoculate with pentaerythritol-producing bacteria.
2. Fermentation is carried out under suitable conditions to produce pentaerythritol.
3. Separate the bacteria and fermentation broth by centrifugation, filtration and other operations, and post-treat the fermentation broth to obtain pentaerythritol with high purity.
The above are three manufacturing methods of pentaerythritol, among which acetaldehyde and glyoxal methods are more commonly used, and biological method is still in the research stage. In actual production, a suitable manufacturing method can be selected according to specific conditions and needs.
