PROCESS FOR THE PREPARATION OF 3,3,5-TRIMETHYLCYCLOHEXYLIDENE BISPHENOL

Abstract

The present invention relates to the preparation of 3,3,5-trimethylcyclohexylidene bisphenol (BP-TMC). Especially, the present invention relates to the preparation of 3,3,5-trimethylcyclohexylidene bisphenol (BP-TMC) from 3,3,5-trimethylcyclohexanone (TMC-one) and phenol in the presence of a gaseous acidic catalyst. The preparation is preferably conducted continuously. It is an object of the present invention to prevent that solids, especially crystallized BP-TMC, more especially crystallized BP-TMC-phenol-adduct, block the outlet of the dosing valve for the gaseous acidic acid when the gaseous acidic acid is dosed into the reaction mixture comprising TMC-one and phenol in a reaction vessel.

Claims

1. A continuously conducted process for the preparation of 3,3,5-trimethylcyclohexylidene bisphenol (BP-TMC) in the presence of a gaseous acidic catalyst, comprising at least the following steps: either (a1) providing a separate first stream comprising: (i) 3,3,5-trimethylcyclohexanone (TMC-one), the TMC-one having a purity of at least 90 wt. %, and the TMC-one comprising less than 1 wt. % phenol, (ii) a gaseous acidic catalyst; (b1) providing a separate second stream comprising: (iii) phenol, (iv) further components; or (a2) providing a separate first stream comprising: (v) phenol, the phenol having a purity of at least 90 wt. %, and the phenol comprising less than 0.5 wt. % TMC-one, (vi) a gaseous acidic catalyst; (b2) providing a separate second stream comprising: (vii) phenol, (viii) TMC-one, (ix) further components; and then (c) bringing together the first stream and the second stream in a reaction vessel to form a reaction mixture.

2. The process of claim 1, wherein in step (a1) in the first separate stream TMC-one is present in an amount of from 40 to 80 wt. % and the gaseous acidic catalyst is present in an amount of from 20 to 60 wt. %, wherein the sum of the amounts of TMC-one and gaseous acidic catalyst is 100 wt.-%.

3. The process of claim 1, wherein in step (b1) in the second separate stream phenol is present in an amount of at least 75 wt. %, further components are present in an amount of less than 25 wt.-%, wherein the sum of the amounts of phenol and further components is 100 wt.-%.

4. The process of claim 1, wherein in step (b1) the separate second stream as further components also comprises TMC-one, BP-TMC and by-products.

5. The process of claim 4, wherein in step (1) in the second separate stream phenol is present in an amount of at least 75 wt. %, TMC-one is present in an amount of less than 6 wt. %, BP-TMC is present in an amount of less than 5 wt. %, by-products are present in an amount of less than 23 wt. %, wherein the sum of the amounts of phenol, TMC-one, BP-TMC, and by-products is 100 wt.-%.

6. The process of claim 1, wherein in step (a2) in the first separate stream phenol is present in an amount of from 40 to 80 wt. %, and the gaseous acidic catalyst is present in an amount of from 20 to 60 wt.-%, wherein the sum of the amounts of phenol and gaseous acidic catalyst is 100 wt.-%.

7. The process of claim 1, wherein in step (b2) in the second separate stream phenol is present in an amount of at least 65 wt. %, TMC-one is present in an amount of 15 to 25 wt.-%, further components are present in an amount of less than 20 wt.-%, wherein the sum of the amounts of phenol, TMC-one and further components is 100 wt.-%.

8. The process of claim 1, wherein in step (b2) the separate second stream as further components also comprises BP-TMC and by-products.

9. The process of claim 8, wherein in step (b2) in the second separate stream phenol is present in an amount of at least 65 wt. %, TMC-one is present in an amount of 15 to 25 wt.-%, BP-TMC is present in amount of less than 5 wt. %, by-products are present in an amount of less than 19 wt.-%, wherein the sum of the amounts of phenol, TMC-one, BP-TMC, and by-products is 100 wt.-%.

10. The process of claim 1, wherein the gaseous acidic catalyst comprises hydrogen sulfide and hydrogen chloride.

11. The process of claim 10, wherein the molar ratio between hydrogen chloride and hydrogen sulfide is from 4:1 to 20:1.

12. The process of claim 1, wherein in regard to the stoichiometric amount the total molar amount of phenol in the first separate stream and the second separate stream is in excess in comparison to the total molar amount of TMC-one in the first separate stream and the second separate stream.

13. The process of claim 1, wherein the ratio between the mass rates of the first separate stream and the second separate stream is from 2:25 to 15:25.

14. The process of claim 1, wherein in a step (d) a product stream comprising from 55 to 70 wt.-% unreacted phenol, less than 5 wt. % unreacted TMC-one, from 15 to 22 wt.-% BP-TMC, and 3.5 to 5.5 wt.-% dissolved acidic catalyst, 0.5 to 2 wt.-%, water, and either from 5 to 20 wt. %, of by-products, or from 1 to 4 wt.-%, of by-products, wherein the sum of the amounts of unreacted phenol, unreacted TMC-one, BP-TMC, water and by-products is 100 wt.-%, is removed from the reaction vessel.

15. The process of claim 1, wherein the TMC-one has a purity of at least 95 wt.-% and the TMC-one comprises less than 0.5 wt.-%

16. The process of claim 1, wherein the TMC-one has a purity of at least 98 wt.-%, and the TMC-one comprises less than 0.2 wt.-% phenol.

17. The process of claim 1, wherein the phenol has a purity of at least 95 wt.-% and the phenol comprises less than 0.2 wt.-% TMC-one.

18. The process of claim 1, wherein the phenol has a purity of at least 99 wt.-% and the phenol comprises less than 0.1 wt.-% TMC-one.

19. The process of claim 2, wherein in step (a1) in the first separate stream TMC-one is present in an amount of from 55 to 65 wt.-% and the gaseous acidic catalyst is present in an amount of from 35 to 45 wt.-%, wherein the sum of the amounts of TMC-one and gaseous acidic catalyst is 100 wt.-%.

20. The process of claim 3, wherein in step (b1) in the second separate stream phenol is present in an amount of at least 85 wt.-% and further components are present in an amount of less than 15 wt.-%, wherein the sum of the amounts of phenol and further components is 100 wt.-%.

Description

[0093] FIG. 1 shows a schematic embodiment of an apparatus according to the state of the art. The reference numbers designate the following items: [0094] 1.1 a first stream comprising mother liquor, [0095] 1.2 a second stream comprising freshly added TMC-one and freshly added phenol, [0096] 1.3 a third stream resulting from the first stream (1.1), the second stream (1.2), [0097] 1.4 a fourth stream comprising a gaseous acidic catalyst, [0098] 1.5 reaction vessel, [0099] 1.6 stirrer, [0100] 1.7 a fifth stream, being a product stream, comprising unreacted phenol, unreacted TMC-one, BP-TMC (BP-TMC-phenol-adduct and dissolved BP-TMC), dissolved acidic catalyst, water and by-products, [0101] 1.8 pump, [0102] 1.9 distillation column, [0103] 1.10 crystallization unit, [0104] 1.11 filtration unit, [0105] 1.12 separated BP-TMC-phenol-adduct, [0106] 1.13 dryer, [0107] 1.14 BP-TMC crystals.

[0108] FIG. 2 shows a schematic embodiment of an apparatus used in a process according to the invention. The reference numbers designate the following items: [0109] 2.1 a first stream comprising phenol of a purity of at least 90 wt.-% and a gaseous acidic catalyst, [0110] 2.2 a second stream comprising freshly added TMC-one, freshly added phenol, and mother liquor comprising unreacted phenol, unreacted TMC-one, dissolved BP-TMC, and by-products, [0111] 2.3 a third stream comprising a mixture of a gaseous acidic catalyst, [0112] 2.4 a fourth stream comprising phenol of a purity of at least 90 wt.-%, [0113] 2.5 a fifth stream comprising freshly added TMC-one and freshly added phenol, [0114] 2.6 reaction vessel, [0115] 2.7 stirrer, [0116] 2.8 a sixth stream, being the product stream, comprising unreacted phenol, unreacted TMC-one, BP-TMC (both BP-TMC-phenol-adduct and dissolved BP-TMC), dissolved acidic catalyst, water, and by-products, this sixth stream is removed from the reaction vessel (2.6), [0117] 2.9 pump, [0118] 2.10 distillation column, [0119] 2.11 crystallization unit, [0120] 2.12 filtration unit, [0121] 2.13 separated BP-TMC-phenol-adduct (crystals), [0122] 2.14 dryer, [0123] 2.15 BP-TMC crystals, [0124] 2.16 mother liquor, comprising unreacted phenol, unreacted TMC-one, dissolved BP-TMC, and by-products, this.

[0125] The following description relates to an embodiment according to the invention using an apparatus depicted schematically in FIG. 2. However, the invention shall not be reduced to this embodiment.

[0126] A first stream (2.1) comprising phenol and a gaseous acidic catalyst is passed into the reaction vessel (2.6). This first stream (2.1) is formed by introducing a third stream (2.3) comprising a gaseous acidic catalyst into a fourth stream (2.4) comprising phenol.

[0127] A second stream (2.2) comprising freshly added TMC-one, freshly added phenol, and mother liquor comprising unreacted phenol, unreacted TMC-one, dissolved BP-TMC, and by-products, is passed into the reaction vessel (2.6), too. This second stream (2.2) is formed by introducing a fifth stream (2.5) comprising freshly added TMC-one and freshly added phenol into an eighth stream (2.11), being a fraction of the sixth stream (2.8).

[0128] In the reaction vessel (2.6), which is a stirred tank reactor with a stirrer (2.7), the BP-TMC is formed by a reaction between TMC-one and phenol in the presence of a gaseous acidic catalyst. Besides BP-TMC water is formed by this reaction. By-products such as isomers of BP-TMC e.g. are formed, too.

[0129] While TMC-one and phenol are present in the liquid state in the reaction vessel (2.6), the formed BP-TMC is present in the solid state in the form of a BP-TMC-phenol-adduct mainly; a minor part of the formed BP-TMC is dissolved in phenol. As the gaseous acidic catalyst is present in the gaseous state the reaction is conducted under three-phase conditions.

[0130] The molar amount of phenol passed into the reaction vessel (2.6) is about 5 to 10, preferably 6 to 7 times the amount which is needed in comparison to the stoichiometric amount of the reaction between TMC-one and phenol to form BP-TMC. This is to ensure that TMC-one reacts to BP-TMC at least nearly quantitatively.

[0131] At the bottom of the reaction vessel (2.6) a sixth stream (2.8), being the product stream, comprising unreacted phenol, unreacted TMC-one, BP-TMC (both BP-TMC-phenol-adduct and dissolved BP-TMC), dissolved acidic catalyst and inert gas is removed from the reaction vessel (2.6). This sixth stream (2.8) is conveyed by a pump (2.9).

[0132] This sixth stream (2.8) is fed to a distillation unit (2.10), where the dissolved acidic catalyst and water are removed from the sixth stream (2.8).

[0133] The sixth stream (2.8) then is fed to a crystallization unit (2.11). In this crystallization unit the dissolved BP-TMC is converted into crystals of a BP-TMC-phenol-adduct.

[0134] After that the sixth stream (2.8) is fed to a filtration unit. BP-TMC-phenol-adduct (2.13), preferably in the form of crystals, is obtained from the filtration unit (2.12). These crystals are dried in a dryer (2.14); after that, BP-TMC in the form of crystals is obtained.

[0135] The remainder of the sixth stream (2.8)—after removing dissolved acidic catalyst and most of the BP-TMC—forms the mother liquor which is enriched with fresh TMC-one and fresh phenol and is conducted back as seventh stream (2.16), the joined stream forming the second stream (2.2).