Butyl acetate
Butyl acetate, also known as butyl acetate, is a colorless, transparent liquid with a pleasant fruity aroma. This substance is an important organic compound and is widely used in the chemical industry.

Applications
1. ** Coatings and Paints **: As an excellent solvent, it has strong solubility to a variety of resins such as nitrocellulose, ethyl cellulose, polystyrene, methacrylic resin, etc. In the paint industry, it greatly improves the application performance and drying speed of coatings, making the coating uniform, flat and smooth. It is widely used in automotive paints, furniture paints, architectural coatings, etc.
2. ** Ink **: It is a commonly used solvent in inks, which can adjust the viscosity of the ink, promote the ink to better transfer and adhere to the surface of the printing material during the printing process, and improve the printing quality. It is used in offset printing inks, gravure printing inks, etc.
3. ** Fragrance **: has a pleasant and fruity aroma. It is used in trace amounts to prepare food flavors and daily flavors, adding a unique aroma to food, beverages, perfumes, air fresheners, etc.
4. ** Medicine **: It is used as a solvent or extractant in pharmaceutical preparations to assist in the dissolution and extraction of pharmaceutical ingredients, which is conducive to the preparation and purification of drugs.

Properties
1. ** Physical properties **: Boiling point is about 126.5 ° C, melting point -73.5 ° C, relative density is 0.8825 (20/4 ° C), slightly soluble in water, miscible with most organic solvents such as alcohols and ethers. Its vapor is heavier than air and can spread to a considerable distance at a lower place. In case of fire, it will catch fire and backfire.
2. ** Chemical properties **: It is an ester compound and has the general chemical properties of esters. Under the catalysis of acid or base, it can undergo hydrolysis reaction to produce acetic acid and butanol; under the catalysis of acid, it can carry out transesterification reaction with alcohol; it can burn and completely burn to produce carbon dioxide and water.

Production
1. ** Direct esterification method **: Using acetic acid and n-butanol as raw materials, under the action of acidic catalysts such as concentrated sulfuric acid, butyl acetate is formed by heating and refluxing. The reaction formula is: $CH_3COOH + C_4H_9OH\ stackrel {H_2SO_4} {\ rightleftharpoons} CH_3COOC_4H_9 + H_2O $. After the reaction, the product is purified by neutralization, washing with water, and distillation. This method has mature technology and easy availability of raw materials, but strong sulfuric acid corrosion and many side reactions.
2. ** Transesterification method **: Using ethyl acetate and n-butanol as raw materials, the transesterification reaction is carried out under the action of catalysts to generate butyl acetate. Common catalysts include titanate esters, organotin, etc. The reaction conditions of this method are mild, less corrosive to equipment, high product quality, but the cost of raw materials is relatively high.
3. ** Biological fermentation method **: Synthesis of butyl acetate catalyzed by enzymes produced by microbial fermentation. Some yeast, bacteria and other microorganisms can convert raw materials such as sugars and alcohols into butyl acetate under specific conditions. This method is green and environmentally friendly, and the conditions are mild, but the fermentation process is complicated to control, and the production efficiency needs to be improved.