Preparation method of dibasic alcohol dicarboxylic acid ester

Abstract

The invention relates to a preparation method of dibasic alcohol dicarboxylic acid ester. The method includes: in the presence of a catalyst, subjecting dibasic alcohol and benzoic acid, and / or alkylbenzoic acid to contact reaction, and removing the water generated by the reaction at the same time; wherein the catalyst is a bulk phase catalyst containing silicon, tin and oxygen and containing Sn-O-Si bond. The method adopted by the invention can reach high conversion rate and selectivity when the reactant dosage is close to the stoichiometric ratio of the reaction, the circulating materials are few, and the atomic economy is stronger.

Description

technical field

[0001] The present invention relates to a kind of preparation method of dibasic alcohol dicarboxylate, in particular to a kind of preparation method of dibasic alcohol dibenzoate and / or dibasic alcohol dialkylbenzoate that can be used as plasticizer . Background technique

[0002] Plasticizers are the most widely used additives in plastic processing. Phthalates have excellent plasticizing properties and relatively cheap production raw materials, so they occupy a large share of the plasticizer market, but since they were found to be carcinogenic, their use has gradually been limited. Glycol dibenzoate has low toxicity and performance equivalent to phthalate. It is a good substitute of phthalate and has a broad market prospect.

[0003] CN102816068A mentioned that in the traditional production method of diethylene glycol dibenzoate, benzoic acid and diethylene glycol are used as raw materials, wherein the benzoic acid needs to be in excess. CN101407461A ment...

Examples

preparation example Construction

[0045] The present invention provides a kind of preparation method of dibasic alcohol dicarboxylate, comprising: in the presence of catalyst, dibasic alcohol and benzoic acid and / or alkyl benzoic acid are contacted and reacted, and the water generated by reaction is removed simultaneously; The catalyst is a bulk phase catalyst containing silicon, tin and oxygen and contains Sn-O-Si bonds.

[0046] According to the present invention, the dihydric alcohol is diethylene glycol, triethylene glycol, 2,2'-dihydroxydipropyl ether (dipropylene glycol), ethylene glycol, 1,3-propanediol and 1,3-butanediol one or more of them.

[0047] According to the present invention, under reflux state, the reaction is performed for 2h-10h, preferably for 3h-6h.

[0048] According to the present invention, the molar ratio of acid to alcohol is (1:0.4)˜(1:0.9), preferably (1:0.52)˜(1:0.6).

[0049] According to the present invention, as a means to adjust the reflux and / or a measure to protect the re...

preparation Embodiment 1

[0097] Get 2.26g stannous chloride dihydrate (SnCl 2 2H 2 O) be dissolved in 10ml deionized water, get Na 2 O SiO 2 9H 2 O was dissolved in deionized water. Add the two solutions into the flask at the same time at 30°C, feed the Si / Sn ratio to 1, add ammonia solution to adjust the pH value to 6, after the precipitation is complete, keep it at 50°C for 2 hours, filter, wash with water, °C, and then baked at 300 °C for 3 hours under the protection of nitrogen to obtain the tin catalyst of the present invention, code A.

[0098] According to XRF analysis, the Si / Sn molar ratio of the catalyst is 0.96.

[0099] According to XPS analysis, the atomic mass fraction of tin on the surface of the catalyst is 5.12%; through ICP analysis, the mass fraction of tin in the catalyst is 63.5%.

preparation Embodiment 2

[0101] Get 2.26g stannous chloride dihydrate (SnCl 2 2H 2 O) be dissolved in 80ml concentration and be in the hydrochloric acid aqueous solution of 1mol / L, take Na 2 O SiO 2 9H 2 O was dissolved in deionized water. Add the two solutions into the flask at the same time at 30°C, feed the Si / Sn ratio of 5, add ammonia solution to adjust the pH value to 7, after the precipitation is complete, continue to keep at 30°C for 2 hours, filter, wash, and dry at 80°C °C, and then baked at 250 °C for 4 hours under the protection of nitrogen to obtain the tin catalyst of the present invention, code B.

[0102] According to ICP analysis, the mass fraction of tin in the catalyst is 27.2%.

technical field

[0001] The present invention relates to a kind of preparation method of dibasic alcohol dicarboxylate, in particular to a kind of preparation method of dibasic alcohol dibenzoate and / or dibasic alcohol dialkylbenzoate that can be used as plasticizer . Background technique

[0002] Plasticizers are the most widely used additives in plastic processing. Phthalates have excellent plasticizing properties and relatively cheap production raw materials, so they occupy a large share of the plasticizer market, but since they were found to be carcinogenic, their use has gradually been limited. Glycol dibenzoate has low toxicity and performance equivalent to phthalate. It is a good substitute of phthalate and has a broad market prospect.

[0003] CN102816068A mentioned that in the traditional production method of diethylene glycol dibenzoate, benzoic acid and diethylene glycol are used as raw materials, wherein the benzoic acid needs to be in excess. CN101407461A ment...

Examples

preparation example Construction

[0045] The present invention provides a kind of preparation method of dibasic alcohol dicarboxylate, comprising: in the presence of catalyst, dibasic alcohol and benzoic acid and / or alkyl benzoic acid are contacted and reacted, and the water generated by reaction is removed simultaneously; The catalyst is a bulk phase catalyst containing silicon, tin and oxygen and contains Sn-O-Si bonds.

[0046] According to the present invention, the dihydric alcohol is diethylene glycol, triethylene glycol, 2,2'-dihydroxydipropyl ether (dipropylene glycol), ethylene glycol, 1,3-propanediol and 1,3-butanediol one or more of them.

[0047] According to the present invention, under reflux state, the reaction is performed for 2h-10h, preferably for 3h-6h.

[0048] According to the present invention, the molar ratio of acid to alcohol is (1:0.4)˜(1:0.9), preferably (1:0.52)˜(1:0.6).

[0049] According to the present invention, as a means to adjust the reflux and / or a measure to protect the re...

preparation Embodiment 1

[0097] Get 2.26g stannous chloride dihydrate (SnCl 2 2H 2 O) be dissolved in 10ml deionized water, get Na 2 O SiO 2 9H 2 O was dissolved in deionized water. Add the two solutions into the flask at the same time at 30°C, feed the Si / Sn ratio to 1, add ammonia solution to adjust the pH value to 6, after the precipitation is complete, keep it at 50°C for 2 hours, filter, wash with water, °C, and then baked at 300 °C for 3 hours under the protection of nitrogen to obtain the tin catalyst of the present invention, code A.

[0098] According to XRF analysis, the Si / Sn molar ratio of the catalyst is 0.96.

[0099] According to XPS analysis, the atomic mass fraction of tin on the surface of the catalyst is 5.12%; through ICP analysis, the mass fraction of tin in the catalyst is 63.5%.

preparation Embodiment 2

[0101] Get 2.26g stannous chloride dihydrate (SnCl 2 2H 2 O) be dissolved in 80ml concentration and be in the hydrochloric acid aqueous solution of 1mol / L, take Na 2 O SiO 2 9H 2 O was dissolved in deionized water. Add the two solutions into the flask at the same time at 30°C, feed the Si / Sn ratio of 5, add ammonia solution to adjust the pH value to 7, after the precipitation is complete, continue to keep at 30°C for 2 hours, filter, wash, and dry at 80°C °C, and then baked at 250 °C for 4 hours under the protection of nitrogen to obtain the tin catalyst of the present invention, code B.

[0102] According to ICP analysis, the mass fraction of tin in the catalyst is 27.2%.

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