1.4-Butanediol (BDO) is an important organic chemical raw material, widely used in polymers, solvents, plasticizers, pharmaceuticals, pesticides and other fields. The following are several common manufacturing methods of 1.4-butanediol:
1. Acetylene aldehyde method
Acetylene aldehyde method is to produce 1,4-butanediol by taking acetylene and formaldehyde as raw materials, after addition, hydrogenation, refining and other steps. This method has the advantages of easy availability of raw materials, mild reaction conditions and high selectivity, and is one of the widely used methods at home and abroad. The specific steps are as follows:
(1) acetylene and formaldehyde in alkaline absorbent additive reaction to produce 1,4-butynediol;
(2) 1,4-butynediol by catalyst under the action of hydrogenation reaction to produce 1,4-butylene diol;
(3) 1,4-butylene diol in the acidic condition of water addition reaction to produce 1,4-butanediol.
2. Maleic Anhydride Method
The maleic anhydride method uses maleic anhydride as the raw material to produce 1,4-butanediol through hydrogenation, hydrolysis and other reactions. This method has the advantages of easy availability of raw materials, mild reaction conditions, no catalyst residue, etc., but the product yield is low. The specific steps are as follows:
(1) 1,4-butanedioic acid is produced by hydrogenation of maleic anhydride under the action of a hydrogenation catalyst;
(2) 1,4-butanedioic acid is produced by hydrolysis of 1,4-butanediol under the action of a hydrolysis catalyst.
3. Butadiene method
Butadiene method is to produce 1,4-butanediol by oxidizing, hydrolyzing and hydrogenating butadiene as raw material. This method has the advantages of easy availability of raw materials, fewer reaction steps and higher product purity, but the reaction conditions are more demanding. The specific steps are as follows:
(1) 1,4-dihydroxy-2-butanone is produced by oxidizing butadiene under the action of oxidizing agent;
(2) 1,4-dihydroxy-2-butanone is hydrolyzed under the action of hydrolysis catalyst to produce 1,4-butanedial;
(3) 1,4-butanedial is hydrogenated under the action of hydrogenation catalyst to produce 1,4-butanediol.
All the above three methods can produce 1,4-butanediol, but different methods have different advantages and disadvantages, and the appropriate method should be chosen according to the specific situation. No matter which method is used, the reaction conditions and raw material quality need to be strictly controlled to ensure the quality and yield of the product.
