Manufacturing Method of Heptanediol
Heptanediol is an important raw material for chemical production, widely used in pharmaceuticals, pesticides, fragrances, cosmetics and other fields. This article will introduce the manufacturing method of heptanediol.
I. The nature and use of heptanediol
Heptanediol is a colorless and transparent liquid with a slight odor, has a high boiling and melting point, insoluble in water, soluble in organic solvents. Heptanediol has a wide range of uses, can be used as solvents, plasticizers, humectants, stabilizers, etc. It can also be used in the production of pesticides, pharmaceutical intermediates and spices.
II. Manufacturing method of heptanediol
1. Chloroheptane method
Chloroheptane method is one of the main methods for manufacturing heptanediol. This method takes chloroheptane as raw material, and makes heptanediol through hydrolysis, reduction and other steps. The specific steps are as follows:
(1) Hydrolysis of chloroheptane: Mix chloroheptane with aqueous sodium hydroxide solution and react with heating and reflux to produce sodium heptanol and sodium chloride.
(2) Acidification of sodium heptanol: sodium heptanol is acidified with hydrochloric acid to produce heptanol and sodium chloride.
(3) Reduction of heptanol: heptanol is reduced with hydrogen to produce heptanediol.
2. Heptanoic Acid Method
The Heptanoic Acid Method is a method of manufacturing heptanediol from heptanoic acid. The method reacts heptanoic acid with formaldehyde and hydrogen in the presence of a catalyst to produce heptanediol. The specific steps are as follows:
(1) Reaction between heptanoic acid and formaldehyde: Heptanoic acid is mixed with formaldehyde and reacted by heating to produce heptanal.
(2) Hydrogenation reduction of heptanal: react heptanal with hydrogen in the presence of catalyst to produce heptanediol.
III. Precautions in the manufacturing process
1. Control the reaction temperature and time: In the manufacturing process, it is necessary to control the reaction temperature and time to ensure the smooth progress of the reaction and the purity of the product.
2. Selecting suitable catalyst: The selection of catalyst has an important influence on the rate and selectivity of the reaction, and it is necessary to select suitable catalyst according to the specific reaction conditions and requirements.
3. Preventing the occurrence of side reactions: In the manufacturing process, attention needs to be paid to prevent the occurrence of side reactions to ensure the purity and yield of the product.
IV.CONCLUSION
Heptanediol is an important raw material for the production of chemicals and has a wide range of uses. Chloroheptane method and heptanoic acid method are the main methods to manufacture heptanediol, and the suitable manufacturing method needs to be selected according to the specific conditions and requirements. During the manufacturing process, attention needs to be paid to controlling the reaction temperature and time, selecting suitable catalysts as well as preventing the occurrence of side reactions to ensure the purity and yield of the product.
