The hottest p-hydroxybenzoic acid has broad develo

2022-10-16
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P-hydroxybenzoic acid has broad development prospects

p-hydroxybenzoic acid is also known as p-cresoic acid, p-hydroxybenzoic acid, molecular formula c7h6o3, white prism crystal, easily soluble in hot water and ethanol, soluble in ether and acetone, slightly soluble in benzene, insoluble in carbon disulfide, and soluble in 125 parts of cold water. Hydroxybenzoic acid is mainly used as the basic raw material of fine chemical products. Parabens, namely p-hydroxybenzoic acid esters, have been widely used as preservatives for food, medicine and cosmetics. It is also widely used in the preparation of various dyes, fungicides, color film and various oil soluble couplers. P-hydroxybenzoic acid polyester, a new high-temperature resistant polymer with wide applications, is also used as the basic raw material

the preliminary survey results of the domestic market in May 2016 show that the annual demand for this product in relevant domestic industries is about 1500 tons, which accounts for a large proportion in the cosmetics and pharmaceutical industries, and some manufacturers' products are exported in large quantities. They are mainly used for antisepsis, sterilization and disinfectant. According to statistics, 39.5% is used in cosmetics, 13.2% is used in food additives, and 47.3% is used in medicine, fiber raw materials, etc. It is understood that due to the micro toxicity and non irritation of Nipagin Esters, the United States has used it as the preferred preservative in the cosmetics industry as a regulation. In China, there are only a few manufacturers such as Jiangsu Funing paint factory, Zhejiang Huangyan No. 2 Chemical Factory and Guangzhou Donghu chemical factory

at present, the product is synthesized in industry with toluene sulfonyl chloride as raw material through ammoniation, oxidation, salting out, alkali melting and acid precipitation; There is a method of salifying salicylic acid, transposition and reacidation. The most commonly used classical methods are the solid-phase method of direct reaction with potassium phenolate and the liquid-phase method of reaction in the presence of excess phenol

recently, a domestic university has developed a product that takes phenol and potassium hydroxide as raw materials, adds the third component, removes water, adds carbon dioxide, and is purified after post-treatment after the reaction. The technology uses compound solvent as the reaction medium and a new post-treatment process. The whole production process adopts closed-circuit circulation, which makes the new process have the following characteristics:

(1) reaction conversion, high selectivity, fast reaction speed, and it is also the standard to judge the accuracy of spring testing machine. It is carried out at low pressure

(2) the post-treatment of the product is simple, and the purity of the crude product is more than 98%

(3) the closed-circuit circulation process makes the total yield of the product more than 90%

(4) put an end to the discharge of toxic waste gas and waste water

at the same time, the industrial device of this product was studied and achieved success

it is estimated that this process will be used to build a production unit with an annual output of 200 tons of p-hydroxybenzoic acid. The total investment is 3.2 million yuan, the sales revenue is 5 million yuan, and the annual profit is 1.8 million yuan. The economic benefits are very considerable

p-hydroxybenzoic acid, also known as p-cresoic acid, p-hydroxybenzoic acid, molecular formula c7h6o3, white prism crystal, easily soluble in hot water and ethanol, soluble in ether and acetone, slightly soluble in benzene, insoluble in carbon disulfide, soluble in 125 parts of cold water. Hydroxybenzoic acid is mainly used as the basic raw material of fine chemical products. Parabens, namely p-hydroxybenzoic acid esters, have been widely used as preservatives in food, medicine and cosmetics. It is also widely used in the preparation of various dyes, fungicides, color film and various oil soluble couplers, A new high-temperature resistant polymer p-hydroxybenzoic acid polyester with a wide range of applications, such as many users of reinforcement factories, also take this as the basic raw material

the preliminary investigation on the domestic market has laid the foundation for the steady growth and stable situation of Jiaozuo City. The results show that the annual demand for this product in relevant domestic industries is about 1500 tons, which accounts for a large proportion in the cosmetics and pharmaceutical industries, and the products of some manufacturers are exported in large quantities. They are mainly used for antisepsis, sterilization and disinfectant. According to statistics, 39.5% is used in cosmetics, 13.2% is used in food additives, and 47.3% is used in medicine, fiber raw materials, etc. It is understood that due to the micro toxicity and non irritation of Nipagin Esters, the United States has used it as the preferred preservative in the cosmetics industry as a regulation. In China, there are only a few manufacturers such as Jiangsu Funing paint factory, Zhejiang Huangyan No. 2 Chemical Factory and Guangzhou Donghu chemical factory

at present, the product is synthesized in industry with toluene sulfonyl chloride as raw material through ammoniation, oxidation, salting out, alkali melting and acid precipitation; There is a method of salifying salicylic acid, transposition and reacidation. The most commonly used classical methods are the solid-phase method of direct reaction with potassium phenolate and the liquid-phase method of reaction in the presence of excess phenol

recently, a domestic university has developed a product that takes phenol and potassium hydroxide as raw materials, adds the third component, removes water, adds carbon dioxide, and is purified after post-treatment after the reaction. The technology uses compound solvent as the reaction medium and a new post-treatment process. The whole production process adopts closed-circuit circulation, which makes the new process have the following characteristics:

(1) the reaction conversion is high, the selectivity is high, the reaction speed is fast, and it is carried out at low pressure

(2) the post-treatment of the product is simple, and the purity of the crude product is more than 98%

(3) the closed-circuit circulation process makes the total yield of the product more than 90%

(4) put an end to the discharge of toxic waste gas and waste water

at the same time, the industrial device of this product was studied and achieved success

it is estimated that this process will be used to build a production unit with an annual output of 200 tons of p-hydroxybenzoic acid. The total investment is 3.2 million yuan, the sales revenue is 5 million yuan, and the annual profit is 1.8 million yuan. The economic benefits are very considerable

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