Method for preparing mixed benzol dioctyl phthalate and benzene acetic acid

Abstract

The invention employs industrial raw material of mixed xylene (xylene for short) as raw material to generate, via oxidation, a mixture of mixed benzene dicarboxylic acid (MA) and phenylacetic acid, and then phenylacetic acid products can be obtained by separation and purification. The mixed phthalic acid (MA) (a mixture of terephthalic acid, m-phthalic acid and phthalic acid) is refined to obtain high-purity mixed phthalic acid (PMA) products. The pure mixed phthalic acid (PMA) products, skipping the production procedures of para-xylene (PX), is a novel raw material of polyester resin, which can generate poly-mixed polyethylene terephthalate (PEM) via esterification and condensation polymerization as an alternative of pure terephthalic acid (PTA) with ethylene glycol (EG). Compared with general polyethylene terephthalate (PET), the poly-mixed polyethylene terephthalate (PEM) has the characteristic of low melting point, and is suitable for being used as a plastic raw material and low in production cost. The pure mixed phthalic acid (PMA) can be mixed with the pure terephthalic acid (PTA) in accordance with random proportion and is used for preparing various differentiated polyester resins, such as bottle grade polyester resin, film grade polyester resin and the like.

Description

Technical field [0001] The invention belongs to the field of petrochemical industry, and is a new manufacturing method of chemical products. Mixed phthalic acid (PMA) is a new product whose main components are isophthalic acid, terephthalic acid and phthalic acid (phthalic anhydride). Mixed phthalic acid (PMA) can be used as a raw material for a new type of polyester resin - polyethylene mixed phthalate, and can also be mixed with purified terephthalic acid (PTA) in various proportions to produce different performance and Polyester resin for use. [0002] Phenylacetic acid is a fine chemical raw material with a wide range of uses, and can be used in medicine, spices, dyes, pesticides and plant growth regulators. Background technique [0003] The current polyester industry chain product and technology route is: aromatics extraction → mixed xylene (MX) → p-xylene (PX) → purified terephthalic acid (PTA) → polyester (PET), excluding polyester downstream Industry is four produ...