Method for co-producing 2, 6-butylated hydroxytoluene and m-cresol as well 6-tertiry butyl m-cresol by utilizing cresol mixture

Abstract

The invention relates to a method for co-producing 2, 6-butylated hydroxytoluene and m-cresol as well 6-tertiry butyl m-cresol by utilizing a cresol mixture. The method comprises the steps of: feeding the cresol mixture and a catalyst into a reaction kettle to be sufficiently mixed in proportion, and then introducing isobutene, wherein the initial reaction temperature is 120-130 DEG C; cooling for five hours until the temperature reaches 60-70 DEG C, then carrying out alkylation to obtain an alkylation solution mainly containing the 2, 6-butylated hydroxytoluene and 4, 6-butylated m-cresol, and refining, wherein the 2, 6-butylated hydroxytoluene with the content of 99% is obtained at the top of a tower, and the 4, 6-butylated m-cresol and the catalyst are produced at the bottom of the tower and sent to the reaction kettle; and carrying out cracking reaction on the 4, 6-butylated m-cresol and the catalyst at the temperature of 120-210 DEG C, and refining, wherein m-cresol with the content of 99% and 6-tertiry butyl m-cresol with the content of 99% are respectively obtained at the top of the tower. Compared with other technologies, the method has the characteristics of being short in reaction time, low in cost, strong in industrial feasibility and the like and the yield is high.

Description

technical field [0001] The invention relates to a method for co-producing 2,6-di-tert-butyl-p-cresol, m-cresol and 6-tert-butyl-m-cresol, especially suitable for producing 2,6-di-tert-butyl-p-cresol with mixed m-p-cresol as raw material Di-tert-butyl p-cresol and m-cresol and 6-tert-butyl m-cresol. Background technique [0002] 2,6-di-tert-butyl-p-cresol, commonly known as T501, BHT, 264, is a phenolic antioxidant. Widely used in plastics, rubber, petroleum products and food industries, it has the advantages of superior performance and moderate price, and its dosage occupies the first place among phenolic antioxidants. m-cresol is an important raw material for the synthesis of pesticides, dyes, antioxidants, vitamin E, medicines and spices. 6-tert-butyl m-cresol (referred to as 3M6B) is also an important chemical intermediate, used as an antioxidant. Widely used in chemical additives, plastics, rubber, petroleum products, synthetic materials and other production fields. ...

AI Technical Summary

Problems solved by technology

However, the current price of BHT products is equivalent to the price of raw material p-cresol, which makes the original process impossible to implement

The method of industrial production of 6-tert-butyl m-cresol is similar to the production of BHT, the difference is that the raw material used for production is m-cresol, but it also faces the same dilemma

[0004] In addition, the raw material used in the present invention is mixed m-cresol, its industrial source is generally prepared by chemical synthesis or extracted from coal tar, this type of material initially contains three isomers, i.e. o-cresol, p-cresol, The trimixed cresol of m-cresol, in which the boiling point of o-cresol is about 9°C lower than that of m-p-cresol, it can be separated by rectification to obtain pure o-cresol, while the difference between the boiling points of m-cresol and p-cresol is only 0.4°C , it is difficult to separate it to obtain pure product by general rectification method, so p-cresol is cheap in raw material mixing, but it has not been well applied

Although there are many methods for separating and mixing m-cresol at home and abroad, such as more than ten kinds of high-pressure crystallization separation method, molecular sieve adsorption method, azeotropic fractionation method, dissociation extraction method, complex method, etc., most of them cannot be obtained due to various problems. Realize industrial application