Processes for the manufacture of secondary fatty alcohols, internal olefins and internal olefin sulfonates

Abstract

Process P.sup.1 for the manufacture of a secondary fatty alcohol, said process P.sup.1 comprising synthesizing an internal ketone K1 by a process P.sup.0 comprising the decarboxylative ketonization reaction of a fatty acid or the like in a liquid phase with a metal compound as catalyst in a reaction medium, wherein a ketone K.sup.2 at liquid state, which is identical or similar to the internal ketone K.sup.1, is introduced into the reaction medium, and subjecting the internal ketone K.sup.1 to a hydrogenation reaction with hydrogen gas as hydrogenating agent to form the secondary fatty alcohol. Use of the secondary fatty alcohol manufactured by the process P.sup.1 for the manufacture of an internal olefin or of an internal olefin sulfonate.

Claims

1. A process P.sup.1 for the manufacture of a secondary fatty alcohol, said process P.sup.1 comprising: synthesizing an internal ketone K.sup.1 by a process P.sup.0 comprising the decarboxylative ketonization reaction of a fatty acid, a fatty acid derivative, or a mixture thereof in a liquid phase with a decarboxylative ketonization catalyst comprising a metal compound in a reaction medium, wherein a ketone K.sup.2 at liquid state, which is identical or similar to the internal ketone K.sup.1, is introduced into the reaction medium, and subjecting the internal ketone K.sup.1 to a hydrogenation reaction with hydrogen gas as hydrogenating agent to form the secondary fatty alcohol, wherein the fatty acid and the fatty acid derivative independently comprise one or more compounds derived from a fatty acid cut, wherein the one or more compounds comprise a hydrocarbon chain having from 4 to 28 carbon atoms attached to a terminal carboxyl group.

2. The process P.sup.1 according to claim 1, wherein the ketone K.sup.2 has a boiling point of at least 270° C.

3. The process P.sup.1 according to claim 1, wherein the difference between the boiling point of the ketone K.sup.1 and the boiling point of the ketone K.sup.2 is equal to or lower than 40° C.

4. The process P.sup.1 according to claim 1, wherein a fatty acid is used as starting material and the fatty acid is a mixture of carboxylic acid selected from the group consisting of caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid and mixtures thereof.

5. The process P.sup.1 according to claim 1, wherein the reaction medium is substantially free of third solvents.

6. The process P.sup.1 according to claim 1, wherein the ketone K.sup.2 is identical to ketone K.sup.1 and has been synthesized in accordance with a previous process P.sup.0.

7. The process P.sup.1 according to claim 1, wherein the process P.sup.0 comprises the steps of: a) introducing in any order at least part of the ketone K.sup.2 at liquid state, at least part of the metal compounds, at least part of the fatty acid, fatty acid derivative or mixture thereof into a reactor in order to synthesize the ketone K.sup.1, said reactor optionally containing before said introduction, a part of the metal compounds, and/or a part of the fatty acid, fatty acid derivative or mixture thereof and/or a part of the ketone K.sup.2 and/or a part of the ketone K.sup.1, b) recovering the ketone K.sup.1 optionally together with the ketone K.sup.2, c) optionally recycling at least part of the ketone K.sup.1 and/or ketone K.sup.2 and/or at least part of the metal compounds to step a).

8. The process P.sup.1 according to claim 7, wherein step a) of process P.sup.0 comprises the steps of: a1) introducing at least part of the ketone K.sup.2 at liquid state, and at least part of the metal compounds into a reactor, said reactor being free of fatty acid(s) and fatty acid derivatives(s), a2) introducing the fatty acid, fatty acid derivative or mixture thereof into the reactor, optionally with: a part of the metal compounds, and/or a part of the ketone K.sup.2.

9. The process P.sup.1 according to claim 7, wherein at step a) of process P.sup.0, the fatty acid, fatty acid derivative or mixture thereof is introduced sequentially or continuously into the reactor.

10. A process P.sup.2 for the manufacture of an internal olefin, said process P.sup.2 comprising: manufacturing a secondary fatty alcohol by the process P.sup.1 according to claim 1, and converting the secondary fatty alcohol into an internal olefin by a dehydration reaction.

11. A process P.sup.3 for the manufacture of an internal olefin sulfonate, said process P.sup.3 comprising: manufacturing an internal olefin by the process P.sup.2 according to claim 10, sulfonating the internal olefin to form a sultone, and subjecting the sultone to an alkaline hydrolysis, so as to form the internal olefin sulfonate.

12. The process P.sup.1 according to claim 2, wherein the ketone K.sup.2 has a boiling point of at least 290° C.

13. The process P.sup.1 according to claim 3, wherein the difference between the boiling point of the ketone K.sup.1 and the boiling point of the ketone K.sup.2 is equal to or lower than 10° C.

14. The process P1 according to claim 1, wherein the metal compound is selected from the group consisting of magnesium, iron and their oxides.

15. The process P1 according to claim 14, wherein the metal compound is iron powder.

16. The process P.sup.1 according to claim 14, wherein the metal compound is FeO, Fe.sub.3O.sub.4, or Fe.sub.2O.sub.3.

17. The process P.sup.1 according to claim 16, wherein the total amount of fatty acid and fatty acid derivative added in the reaction medium for the decarboxylative ketonization reaction is such that the overall molar ratio of metal to carboxylic groups is in the range of from 1:6 to 1:99.

18. The process P.sup.1 according to claim 1, wherein the temperature of the reaction medium inside the reactor is maintained from 285° C. to 350° C. during the decarboxylative ketonization reaction.

19. The process P.sup.1 according to claim 1, wherein an intermediate metal carboxylate salt which is substantially soluble in the reaction medium is formed through an initial reaction between the fatty acid or its derivative with the metal compound.

20. The process P.sup.1 according to claim 1, wherein the process P.sup.0 is a batch process.

21. The process P.sup.1 according to claim 4, wherein the mixture of fatty acids comprises a fatty acid cut obtained from coconut oil.

Description

EXAMPLES

Example 1—Synthesis of a C.SUB.15.-C.SUB.35 .Ketones Cut Starting from a C.SUB.8.-C.SUB.18 .Coco Saturated Fatty Acids Cut (in Accordance with the Process Described in WO 2016177842)

(1) The reaction is carried under argon in a 750 ml reactor equipped with mechanical stirring, Dean-Stark apparatus and an addition funnel. In the reactor, 6.8 g (0.12 mol) of iron powder is dispensed and 200 g (0.97 mol) of the coco saturated fatty acids cut (with the following distribution: C.sub.8: 7 wt %, C.sub.10: 8 wt %, C.sub.12: 48 wt %, C.sub.14: 17 wt %, C.sub.16: 10 wt %, C.sub.18: 10 wt %) are introduced into the addition funnel.

(2) A first partial amount of 50 g of fatty acids is added into the reactor and the temperature is brought to 250° C. The mixture is stirred at this temperature during 4 h. During this time the color of the media changes to black and H.sub.2 gas is released. FTIR analysis of the crude mixture shows complete formation of intermediate iron carboxylate complexes.

(3) The temperature is then raised to 330° C. and the mixture is stirred at this temperature during 2 h. During this period of time, the intermediate iron carboxylate complexes are decomposed to fatty ketones, iron oxide and CO.sub.2.

(4) The remaining fatty acids (150 g) are slowly introduced into the reactor, at a flow rate such that the temperature of the reaction medium does not fall down below 320° C. and which allows keeping the concentration of fatty acids in the reaction medium very low. An average addition flow rate of around 25 g fatty acids/hour proves to be satisfactory. Practically, this is achieved through the successive slow additions (1 hour per addition) of 3 portions of 50 g of melted fatty acids followed by 1 hour of stirring at 330° C. between each addition.

(5) At the end of the third and last addition, the crude medium is stirred at 330° C. during 2 h and the reaction progress is monitored through FTIR. When the reaction is completed (no more iron complex detected by FTIR), the mixture is allowed to cool down at room temperature and 400 ml of CHCl.sub.3 is added to the crude media. The mixture is stirred at 40° C. in order to solubilize the product (C.sub.15-C.sub.35 ketones). The obtained suspension is filtered on a silica plug (400 g) and eluted using 3 liters of chloroform. Evaporation of the solvent affords 161 g (0.46 mol) of the product 015-035 ketones as an analytically pure white wax (95% isolated yield).

Example 2—Ketonization of C.SUB.8.-C.SUB.18 .Fatty Acids Cut Using Magnetite Fe.SUB.3.O.SUB.4 .as the Catalyst (in Accordance with Process P.SUP.0.)

(6) The reaction is carried out under an inert atmosphere of argon.

(7) In a 750 ml reactor equipped with a mechanical stirrer, a Dean-Stark apparatus to trap water generated during the reaction and an addition funnel, are dispensed 40 g of the C.sub.15-C.sub.35 ketones made by example 1 and 9.3 g (0.040 mole) of magnetite Fe.sub.3O.sub.4.

(8) The addition funnel of the reactor is filled with 200 g (0.970 mole) of melted fatty acids (C.sub.8: 7 wt %, C.sub.10: 8 wt %, C.sub.12: 48 wt %, C.sub.14: 17 wt %, C.sub.16: 10 wt %, C.sub.18: 10 wt %).

(9) The reaction mixture is then heated at 330° C. under stirring (500 rpm) and 200 g (0.970 mole) of the melted fatty acids is slowly introduced into the reactor such that the temperature of the reaction medium does not fall down below 320° C. (for example with an addition flow rate of around 25 g fatty acids/hour).

(10) Practically this can be done also through the successive slow additions (1 hour per addition) of 4 portions of 50 g (60 ml) of melted fatty acids followed by 1 hour of stirring at 330° C. after each addition.

(11) At the end of the last addition, the crude medium is stirred at 330° C. during an additional hour and the reaction progress is monitored through FTIR.

(12) At the end of the reaction when the intermediate iron complex is not detected anymore through FTIR (absorption bands at 1550 cm.sup.−1 and 1408 cm.sup.−1), the mixture is allowed to cool down at room temperature and dissolved in 400 ml of CHCl.sub.3.

(13) The obtained solution is filtered through a path of 400 g of silica gel followed by elution with 5 liters of CHCl.sub.3 in order to remove iron oxide.

(14) The chloroform is evaporated under vacuum and the crude product is dried overnight under 10 mbar at 50° C. to obtain about 207 g of ketone (which contains about 167 g of product generated through ketonization of the 200 g of fatty acids in addition to the 40 g of fatty ketones that have been dispensed initially in the reactor) as a light brown wax corresponding to a crude yield of about 98%.

(15) Analysis of the crude shows a GC purity of about 96% (impurities being mainly hydrocarbons) with the following composition for the ketones cut:

(16) C.sub.15: about 0.5 wt %, C.sub.17: about 1.3 wt %, C.sub.19: about 8.4 wt %, 021 about 11.4 wt %, C.sub.23: about 28.4 wt %, C.sub.25: about 19.0 wt %, C.sub.27: about 13.0 wt %, C.sub.29: about 11.7 wt %, C.sub.31: about 3.7 wt %, C.sub.33: about 1.6 wt %, C.sub.35: about 0.9 wt %.

Example 3—Ketonization of C.SUB.8.-C.SUB.18 .Fatty Acids Cut Using Magnetite Fe.SUB.3.O.SUB.4 .as the Catalyst (in Accordance with Process P.SUP.0.)

(17) The reaction is carried out exactly as in example 2 except that the 40 g of C.sub.15-C.sub.35 ketones dispensed in the reactor are not the C.sub.15-C.sub.35 ketones made by example 1, but the C.sub.15-C.sub.35 ketones made by example 2.

(18) As in example 2, about 207 g of ketone are obtained as a light brown wax corresponding to a crude yield of about 98%.

(19) Analysis of the crude shows likewise a GC purity of about 96% (impurities being mainly hydrocarbons) with the following composition for the ketones cut: about 0.5 wt %, C.sub.17: about 1.3 wt %, C.sub.19: about 8.4 wt %, C.sub.21: about 11.4 wt %, C.sub.23: about 28.4 wt %, C.sub.25: about 19.0 wt %, C.sub.27: about 13.0 wt %, C.sub.29: about 11.7 wt %, C.sub.31: about 3.7 wt %, C.sub.33: about 1.6 wt %, C.sub.35: about 0.9 wt %.

Example 4—Ketonization of C.SUB.8.-C.SUB.18 .Fatty Acids Cut Using Fe(III) Oxide Fe.SUB.2.O.SUB.3 .as the Catalyst (in Accordance with Process P.SUP.0.)

(20) The reaction is carried out under an inert atmosphere of argon.

(21) In a 750 ml reactor equipped with a mechanical stirrer, a Dean-Stark apparatus to trap water generated during the reaction and an addition funnel, are dispensed 40 g of C.sub.15-C.sub.35 ketones made by example 2 and 9.74 g (0.060 mole) of Fe.sub.2O.sub.3.

(22) The addition funnel is filled with 200 g (0.970 mole) of melted fatty acids (C.sub.6: 7 wt %, C.sub.10: 8 wt %, C.sub.12: 48 wt %, C.sub.14: 17 wt %, C.sub.16: 10 wt %, C.sub.18: 10 wt %).

(23) The reaction mixture is then heated at 330° C. under stirring (500 rpm) and 200 g (0.970 mole) of the melted fatty acids is slowly introduced into the reactor such that the temperature of the reaction medium does not fall down below 320° C. (for example with an addition flow rate of around 25 g fatty acids/hour).

(24) Practically this can be done through the successive slow additions (1 hour per addition) of 4 portions of 50 g (60 ml) of melted fatty acids with 1 hour of stirring at 330° C. between each addition.

(25) At the end of the last addition, the crude medium is stirred at 330° C. during 0.5 hour and the reaction progress is monitored through FTIR.

(26) At the end of the reaction when the intermediate iron complex is not detected anymore through FTIR (absorption bands at 1550 cm.sup.−1 and 1408 cm.sup.−1), the mixture is allowed to cool down at room temperature and dissolved in 300 ml of CHCl.sub.3.

(27) The obtained solution is filtered through a path of 400 g of silica gel followed by elution with 3 liters of CHCl.sub.3 in order to remove iron oxide.

(28) The chloroform is evaporated under vacuum and the crude product dried overnight under 10 mbar at 50° C. to obtain about 204 g of ketone (about 164 g of product generated through ketonization of the 200 g of fatty acids in addition to the 40 g of fatty ketones that have been dispensed initially in the reactor) as a light brown wax corresponding to a crude yield of about 96%.

(29) Analysis of the crude shows a GC purity of about 97% (impurities being mainly alkanes) with the following composition for the ketones cut:

(30) C.sub.15: about 0.5 wt %, C.sub.17: about 1.2 wt %, C.sub.19: about 8.4 wt %, C.sub.21: about 11.2 wt %, C.sub.23: about 28.6 wt %, C.sub.25: about 19.1 wt %, C.sub.27: about 13.2 wt %, C.sub.29: about 11.4 wt %, C.sub.31: about 3.5 wt %, C.sub.33: about 1.5 wt %, C.sub.35: about 0.7 wt %.

Example 5 (Comparative)—Ketonization of C.SUB.8.-C.SUB.18 .Fatty Acids Cut Using Magnetite Fe.SUB.3.O.SUB.4 .as the Catalyst with Direct Introduction of Entire Amount of Fatty Acids to be Converted and without Initial Introduction of Ketone

(31) The reaction is carried out under an inert atmosphere of argon.

(32) In a 500 ml round bottom flask equipped with a mechanical stirrer and a Dean-Stark apparatus to trap water generated during the reaction, 100 g (0.480 mole) of melted fatty acids (C.sub.8: 7 wt %, C.sub.10: 8 wt %, C.sub.12: 48 wt %, C.sub.14: 17 wt %, C.sub.18: 10 wt %, C.sub.18: 10 wt %) and 4.7 g (0.020 mole) of magnetite Fe.sub.3O.sub.4 are dispensed.

(33) The mixture is then allowed to stir under reflux (330° C. ordered) during 8 hours. The reaction media temperature increases progressively over the course of the reaction from 250° C. (beginning) to 303° C. after 8 hours of stirring. Importantly generation of water is observed and at the end of the reaction GC analysis (normalization) shows approximately that the conversion of fatty acids is around 40% (significant amounts of fatty acids remaining), the selectivity of ketone formation is about 55% and the approximate yield of ketones is only 23%.

Example 6—Conversion of Internal Ketones to Secondary Fatty Alcohols (in Accordance with Process P.SUP.1.)

(34) This example describes the hydrogenation of the internal ketones obtained in accordance with the process P.sup.0 to obtain the corresponding secondary fatty acid alcohols.

(35) The hydrogenation is carried out on a C.sub.15-C.sub.35 cut of internal fatty ketones obtained by example 3 in a 750 ml autoclave equipped with a Rushton turbine, without any added solvent.

(36) 28 g of Pd/C (3%) and 280 g of the C.sub.15-C.sub.35 fatty ketones made by example 3 are introduced into the reactor which is sealed. Then the temperature is brought to 80° C. and the mixture is stirred at 1000 rpm.

(37) The reactor atmosphere is purged 3 times with 4 MPa of nitrogen then 3 times with 3 MPa of hydrogen.

(38) The temperature is then raised to 150° C. and the mixture is stirred at this temperature maintaining 3 MPa of hydrogen until completion of the reaction (monitored by GC analysis).

(39) At the end of the reaction, the mixture is allowed to cool down to 80° C. and the reactor is purged with nitrogen.

(40) A 1.sup.st crop of secondary fatty alcohol product (about 180 g) is obtained through filtration and the remaining part is extracted using 400 ml of hot toluene. After evaporation of the solvent, a total amount of about 247 g of secondary fatty alcohol white solid is obtained corresponding to an isolated yield of about 88%.

(41) The secondary fatty alcohol product is cut of C.sub.15-C.sub.35 secondary alcohols.

Example 7—Dehydration of Secondary Fatty Alcohols to Internal Olefins (in Accordance with Process P.SUP.2.)

(42) In this example, the secondary fatty alcohols obtained in example 6 (according to process P.sup.1) are dehydrated with limited isomerization of C═C bond.

(43) The dehydration reaction is carried out under argon atmosphere, without added solvent and using Al.sub.2O.sub.3-η as a catalyst.

(44) 47 g of a cut of internal alcohols obtained in accordance with example 6 followed by 4.7 g of Al.sub.2O.sub.3-η are added in a round bottom flask equipped with a Dean-Stark apparatus and magnetic stirring. The mixture is then stirred at 300° C. during 2 hours. Water generated during the dehydration reaction is trapped with the Dean-Stark apparatus.

(45) After completion of the dehydration reaction, the product is extracted using 150 ml of hot toluene. After evaporation of the solvent, the product is obtained as pale yellow liquid (about 39 g) corresponding to an isolated yield of about 87%.

(46) The pale yellow liquid product consists essentially of a cut of C.sub.15-C.sub.35 internal olefins with C═C bond localized almost in the middle of the chain.

Example 8—Conversion of Internal Olefins into Internal Olefin Sulfonates (in Accordance with Process P.SUP.3.)

(47) In this example, the liquid internal olefins obtained in example 7 (according to process P.sup.2) are converted into internal olefin sulfonates (IOS).

(48) Firstly, the internal olefins undergo a sulfonation reaction in a falling film (lab scale film) reactor equipped with a cooling jacket supplied with cold water in order to prevent temperature increases in the reactor due to the high exothermicity of the reaction. For this reaction, the temperature of the cooling jacket is set-up at around 4° C.

(49) A gas flow consisting of a mixture of anhydrous SO.sub.3 diluted with carefully dried nitrogen, with a SO.sub.3 concentration usually of 2.5% v/v, is contacted with the falling film of liquid olefins. The flows of gas and liquid phases are set-up in order to ensure a residence time of 3 minutes in the reactor and a mole ratio SO.sub.3:internal olefin of 1.05:1.

(50) Following the sulfonation reaction the mixture exiting the reactor (which is composed mainly of 6-sultones) is allowed to age for 1 day in order to allow isomerization & trans-sulfonation to occur and to increase the conversion of starting olefins.

(51) Thereafter, the obtained mixture is neutralized using an aqueous solution of NaOH (10 wt. %) in a reactor equipped with a mechanical stirring. Hydrolysis is then carried out by heating the mixture under mechanical stirring. During this stage of the process, the sultones are transformed into the desired IOS through a ring opening reaction.

(52) The sulfonation, digestion and hydrolysis reactions are followed using NMR analysis.

Example 9—Conversion of Internal Olefins into Internal Olefin Sulfonates (in Accordance with Process P.SUP.3.)

(53) In this other example, the sulfonation of the liquid internal olefins obtained in example 7 (according to process P.sup.2) is carried out in a batch reactor equipped with a mechanical stirring in the liquid phase using an in-situ prepared sulfonating reagent, namely SO.sub.3-dioxane complex.

(54) In a round bottom flask anhydrous dioxane and anhydrous trichloromethane (mixture ratio 1:35 v/v) are mixed and cooled down to a temperature of 0° C. Then liquid SO.sub.3 (2 molar equivalents) is slowly added under stirring during 10 minutes to generate the complex SO.sub.3-dioxane which precipitates out from the mixture as white crystals.

(55) The internal olefins made according to example 7 (1 equivalent) are then slowly added under stirring at a temperature of 0° C. to the reaction medium during a period of 1 hour and the mixture is allowed to warm up to room temperature. During this time, the color of the mixture changes from light yellow to dark brown and NMR analysis indicates that almost full completion of internal olefins has occurred (around 94% of olefin conversion to sultones). All the volatiles (CHCl.sub.3 and dioxane) are then removed under vacuum.

(56) Then 2.4 equivalents of an aqueous NaOH solution (10 wt. %) are added to the residue and the resulting mixture is stirred at room temperature during 1 hour in order to ensure complete neutralization.

(57) Hydrolysis is then performed by stirring the resulting reaction mixture at 95° C. overnight. NMR analysis indicates full conversion of sultones to internal olefin sulfonates.

(58) At the end of the process the amount of water is adjusted in order to reach an aqueous solution of IOS with a concentration of active matter of 30 wt. %.

Example 10—Conversion of Internal Olefins into Internal Olefin Sulfonates (in Accordance with Process P.SUP.3.)

(59) In accordance with this last example, IOS is prepared by the method of Changxin et al. (Arab. J. Sci. Eng., 2014, vol. 39, pages 37-41).

(60) Sulfonation is carried out in a falling film glass reactor. Gaseous sulfur trioxide is diluted with air, and then passed through the internal fatty olefin obtained by example 7. The ratio of sulfur trioxide to through the internal fatty olefin is 1:1. The concentration of sulfur trioxide in the air is 2.5% by volume. The cooling water inlet temperature is from about 18° C. to about 24° C., and the outlet temperature is from about 23° C. to about 29° C.

(61) No aging of the reaction mixture issued from the sulfonation reactor, hereinafter “the sulfonation product”, is applied.

(62) The sulfonation product is neutralized with sodium hydroxide solution, and then hydrolysed for 30 min at 70° C.

(63) Petroleum ether having a boiling point in the range 60˜90° C. (analytical reagent) is used to extract most of the unreacted internal olefin.

(64) The product is dried, and was next washed with ethanol. The final product is obtained after evaporation of the ethanol.