Process for the hydrogenation of anhydromevalonolactone

Abstract

The invention relates to a process for the manufacturing of biobased 3-methyl-delta-valerolactone (3MdVL) and 3-methyl-1,5-pentanediol (3MPD) via one- pot hydrogenation of anhydromevalonolactone (aMVL) in the presence of a Raney- Nickel catalyst. The hydrogenation occurs without solvent at a temperature from 120ºC-180ºC, preferably at 130ºC-170ºC and a pressure between 15-30 bar, preferably at a pressure between 18 and 22 bar. The hydrogenation time may vary between 3 and 25 hours, preferably between 6 and 24 hours.

Description

[0001] PROCESS FOR THE HYDROGENATION OF ANHYDROMEVALONOLACTONE

[0002] The present invention relates to a process for the manufacturing of biobased 3- methyl-delta-valerolactone or p-methyl-b-valerolactone (3MdVL) and 3-methyl-1,5- pentanediol (3MPD) via the hydrogenation of anhydromevalonolactone or 4-methyl-5,6- dihydro-2H-pyran-2-one (aMVL).

[0003] Lactones are an important class of compounds that can be derived from biomass via biochemical routes and can serve as intermediates for the sustainable production of hydrocarbon bio fuels and other products. In particular, mevalonolactone (MVL) can be derived from biomass fermentation to produce a variety of intermediates.

[0004] Successfully scaling up biobased products is essential for the future to compete with well-established fossil-based chemicals. Biobased alternatives however need to solve the triple equation of environmental, safety and economic performance. They need to be economically viable on an industrial scale and possess properties being superior to existing petroleum-derived analogues. Few biobased products have met this challenge.

[0005] Biobased 3-methyl-delta-valerolactone (3MdVL) is known to improve the sustainability and recyclability of polyurethane (Pll) products and unlock new engineering plastic applications for Polylactic acid (PLA) co-polymers.

[0006] Also biobased 3-methyl 1 ,5-pentanediol (3MPD), is known and can be used as a biobased polyol component in the traditional Pll and other plastic production. 3- methyl-1,5-pentanediol (3MPD) is known to produce soft polyurethanes with good hydrolytic stability and thermal resistance which are used in making shoe soles, spandex-like materials and synthetic leather with end applications in consumer products like bags, furniture covering and shoes.

[0007] In EP-A-2986730, the production of biobased aMVL via fermentation is disclosed. It is further disclosed that anhydromevalonolactone can be hydrogenated by using a Pd / C catalyst under H2 pressure at 4 bar. After reaction at 25°C overnight (~14 hours), p-methyl-b-valerolactone (3MdVL) was obtained with a yield of 87.93%.

[0008] In WO2016077555, the production of 3-methylpentane-1,5-diol (3MPD) is disclosed by reacting biobased anhydromevalonolactone (aMVL), with [Rh(acac) (CO)2], and [Mo(CO)6] in 1,4-dioxane as solvent. The reaction was pressurized with 120 bar hydrogen and heated up to 200 degrees centigrade within 20 min leading to a hydrogen pressure of 150 bar at reaction temperature. A reaction time of 2 h was taken. After the reaction mixture was cooled to room temperature the solvent was evaporated. The product 3MPD was purified by vacuum distillation. (Adapted from: Bimetallic-Catalyzed Reduction of Carboxylic Acids and Lactones to Alcohols and Diols. A. Behr, V. A. Brehme v. Synth. Catal. 2002, 344, 525 - 532).

[0009] Behr, Arno. (2002). Bimetallic-catalyzed reduction of carboxylic Acids and Lactones to Alcohols and Diols. Advanced Synthesis & Catalysis discloses an equimolar mixture of [Rh(acac)(CO)2] and [Mo(CO)6] showing the highest activity and therefore applied to the reduction of lactones into diols.

[0010] In W02007125909, the production of 3-methyl-1,5-pentanediol is disclosed by hydrogenating 2-hydroxy-4-methyltetrahydropyran in the presence of a hydrogenation catalyst such as a Raney-nickel modified with 0.1-10 wt% of molybdenum. The raw material is a non-biobased product.

[0011] A process for the manufacturing of both non biobased 3-methyl-delta- valerolactone (3MdVL) and 3-methyl-1,5-pentanediol (3MPD) is known in the art and disclosed in for example JP-A-62039535. The combined production of 3-methyl-delta- valerolactone (3MdVL) and 3-methyl-1,5-pentanediol (3MPD) is disclosed by using 2- hydroxy-4-methyltetrahydropyran as a starting material or raw material, which reacts in a non-oxidizing gas atmosphere (preferably nitrogen gas or hydrogen gas) at 110-190 deg.C, under a pressure of less than or equal to 50 atm, in the presence of an organic solvent and with a catalyst chosen of an oxide of one or more kinds of metals selected from copper, chromium and zinc such as for example CuO-Cr2O3-MnO2. The starting material here is 2-hydroxy-4-methyltetrahydropyran which is the raw material of polyurethane. This process has the disadvantage that it is not biobased and the catalyst is known to be not environmentally friendly.

[0012] In US2017297983 a process is disclosed for forming a diol compound such as

[0013] 3-methyl-1,5-pentanediol in which the process comprises two steps using two different heterogeneous catalysts at different temperatures and pressures.

[0014] Departments of •chemical Engineering and Materials Science and Chemistry, University of Minnesota, Minneapolis, MN 55455-043 Edited by Malcolm H. Chisholm, The Ohio State University, Columbus, OH, and approved April 11, 2014, Mingyong Xionga-1, Deborah K. Schneidermanb-1, Frank S. Batesa, Marc A. Hillmyerb2, and Kechun Zhanga. discloses the production of block polymers from a sugar biobased route to the branched lactone, p-methyl-b-valerolactone which can be transformed into a rubbery (i.e. , low glass transition temperature) polymer such as polylactide-poly-p- methyl-b-valerolactone-Polylactide triblock polymers.

[0015] It is clear from the prior art that when starting from anhydromevalonolactone or

[0016] 4-methyl-5,6-dihydro-2H-pyran-2-one in general a two steps hydrogenation is required with 2 different catalysts to achieve both biobased products (3MdVL) and (3MPD) in a reasonable yield. The hydrogenation reaction towards 3MPD moreover occurs at high temperatures and pressures in the presence of dioxane as solvent which is not desirable.

[0017] It is an object of the present invention to simplify the above described two-step hydrogenation process of aMVL into 3MdVL and 3MPD. It is a further object of the present invention to simultaneous produce both biobased products 3MdVL and 3MPD in certain amounts with one type of catalyst.

[0018] It is also an object of the present invention to shorten the reaction time of the hydrogenation process whereby the production costs are reduced. It is a further object of the present invention to improve the production efficiency of both 3MdVL and 3MPD in a one pot hydrogenation process.

[0019] The object of the present invention is achieved in that a process is provided for the manufacturing of biobased 3-methyl-delta-valerolactone (3MdVL) and 3-methyl-1 ,5- pentanediol (3MPD) via a one-pot hydrogenation of anhydromevalonolactone (aMVL) in the presence of a Raney-Nickel catalyst.

[0020] The term "biobased" as used in the present invention means that the products 3MdVL and 3MPD are synthesized from a biological precursor, and specifically a renewable biological carbon source, such as biomass (as opposed to a non-renewable petroleum-based carbon source).

[0021] Surprisingly it has been found that the hydrogenation of biobased aMVL can be performed under mild conditions without the use of a solvent. Moreover it has been found that both 3MdVL and 3MPD can be produced simultaneously in one pot and that the yield of 3MdVL and 3MPD can be steered. It also has been found that the obtained products 3MdVL and 3MPD comprise less that 10 wt% of impurities based on the total weight of 3MdVL and 3MPD.

[0022] The one pot hydrogenation is easily applicable on industrial scale, is faster, and more environmentally friendly and cost-effective.

[0023] By mild conditions is meant that the hydrogenation occurs at a temperature between 120-180 °C, preferably a temperature between 130-170 °C. The pressure varies between 15-30 bar, preferably between 18-22 bar. The reaction time varies between 3 and 25 hours, preferably between 6 and 24 hours.

[0024] It has been found that both 3MdVL and 3MPD can be produced simultaneously and that the yield of 3MdVL and 3MPD can be steered. If the hydrogenation temperature varies between 140°C-170°C and the reaction time is between 9-24 hours, more than 55 wt% of 3MPD is produced. If the hydrogenation temperature varies between 130°C-150°C, whereby the reaction time is between 3 -4 hours more than 80 wt% of 3MdVL is produced. Preferably the ratio (3MdVL) / (3MPD) varies between 20 / 80-80 / 20. The hydrogenation reaction starting from aMVL is given in figure 1. The first hydrogenation is converting aMVL into 3MdVL, the next hydrogenation is converting 3MdVL into 3MPD. After hydrogenation both products are distilled from the reaction mixture.

[0025] Biobased anhydromevalonolactone (aMVL), which is the starting material in the hydrogenation process of the present invention can be produced inexpensively by dehydration of mevalonolactone (MVL), a bio-intermediate that can be produced in high yields via fermentation using a variety of biomass feedstock, making aMVL a green and readily accessible bio-based molecule. The production of biobased aMVL is disclosed in for example US2016 / 0145227. In the present invention the raw material is preferably higher than 90% pure.

[0026] The hydrogenation reaction of aMVL into both 3MdVL and 3MPD occurs in one pot with one catalyst being a Raney-nickel catalyst. Usually, the amount of a hydrogenation catalyst to be used is preferably in the range of 10-35 wt% based on the total weight of aMVL. The catalyst is preferably washed with excess water on a filter. The excess water is removed until just wet RaNi is obtained. This ‘water wet’ RaNi is used in the present invention. Preferably the amount of impurities in 3-methyl-delta- valerolactone (3MdVL) and 3-methyl-1 ,5-pentanediol (3MPD) is below 10 wt% based on the total weight of 3MdVL and 3MPD.

[0027] One of the advantages of the process of the present invention is the simultaneously production of 3MdVL and 3MPD in one pot, whereby the yield of 3MdVL and 3MPD can be steered. In case that the hydrogenation temperature varies between 140°C-170°C, whereby the reaction time varies between 9-24 hours more than 55 wt% 3MPD is achieved based on the total weight of the reaction mixture. In case that the hydrogenation temperature varies between 130°C-150°C, whereby the reaction time varies between 3 -4 hours more than 80wt% of 3MdVL is achieved based on the total weight of the reaction mixture. Preferably the achieved amount of 3MdVL is higher than 40wt% and the achieved amount of 3MPD is higher than 10 wt% based on the total weight of the reaction mixture. The reaction mixture further comprising less than 10 wt% impurities based on the total weight of 3-methyl-delta-valerolactone (3MdVL) and 3-methyl-1,5-pentanediol (3MPD). More preferably the achieved amount of 3MdVL is higher than 10 wt% and the achieved amount of 3MPD content is higher than 40 wt% further comprising less than 10 wt% impurities based on the total weight of 3-methyl-delta-valerolactone (3MdVL) and 3-methyl-1,5-pentanediol (3MPD). The present invention will now be described in detail with reference to the following non-limiting examples which are by way of illustration only.

[0028] FIGURES

[0029] Figure 1 represents the hydrogenation reaction starting from aMVL into 3MdVL and 3MPD in which aMVL is produced via fermentation from biomass.

[0030] MATERIALS

[0031] -Raney Nickel (Grace 2800) was washed with excess water on a filter. The excess water was removed until just dry RaNi. This ‘water wet’ RaNi was used in the experiments.

[0032] -CopperChromite obtained from Aldrich.

[0033] ANALYSIS

[0034] Gas Chromatography (GC):

[0035] Analytical instrument: DB- WAX 20m x 180 p I.D., 0.18 p film thickness (GC-in-078) Analytical conditions: injection temperature: 275 degrees C Detection temperature: 250 degrees C Flow: 1ml / min

[0036] The components identified in the syntheses of aMVL to 3MdVL and 3MPD have very similar response factors, making the mutual area% ratio reasonably comparable to the wt% ratio.

[0037] EXAMPLES

[0038] EXAMPLE 1 : One pot hydrogenation of aMVL into 3MdVL and 3MPD:

[0039] 4 gram distilled aMVL and 995 mg water-wet RaNi were reacting with Hydrogen (20 bar) at 130 °C for 3 hours and 15 minutes. No additional solvents were used. After 3h15 hours the reaction temperature was increased to 170 °C and the reaction continued for 6 hours. The final reaction mixture was analysed with Gas Chromatography (GC). It contained 68.4 wt% beta-Methyl-delta-Valerolactone (3MdVL), 26.3 wt% 3-methyl-1,5-Pentanediol (3MPD) and 5.3 wt% impurities.

[0040] EXAMPLE 2: One pot hydrogenation of aMVL into 3MdVL and 3MPD

[0041] 4 gram distilled aMVL and 1010 mg water-wet RaNi were reacting with hydrogen (20 bar) at 150 °C for 3 hours and 15 minutes. No additional solvents were used. After 3 hours and 15 minutes the reaction temperature was increased to 170 °C and the reaction continued for another 6 hours. The final reaction mixture was analyzed by GC. It contained 66.1 wt% of 3MdVL, 25.2 wt% 3MPD and 8,7 wt% impurities.

[0042] EXAMPLE 3: Hydrogenation of 3MdVL with RaNi for 3 hours at 150 °C

[0043] 3.2 gram distilled 3MdVL and 720 mg water-wet RaNi were reacting with hydrogen (20 bar) at 150 °C for 3 hours. No additional solvents were used. The final reaction mixture was analyzed by GC. It contained 87wt% of 3MdVL, 11 wt% 3MPD and 8,7 wt% impurities.

[0044] EXAMPLE 4: Hydrogenation of 3MdVL with RaNi for 3 h at 150 °C and 6 h at 170 °C

[0045] 3.2 gram distilled aMVL and 720 mg water-wet RaNi were reacting with hydrogen (20 bar) at 150 °C for 3 hours. No additional solvents were used. After 3 hours the reaction temperature was increased to 170 °C and the reaction continued for another 6 hours. The final reaction mixture was analyzed by GC. It contained 35 wt% of 3MdVL, 58 wt% 3MPD and 6.3 wt% impurities.

[0046] COMPARATIVE EXPERIMENT I: Hydrogenation of aMVL into 3MdVL and hydrogenation of 3MdVL into 3MPD with Pd / C and RaNi

[0047] Full conversion of aMVL to 3MdVL were obtained in hydrogenation with 10 wt% of 5% Pd / C at 120 °C and 20 bar hydrogen for 4 hours. This reaction comprised THF as solvent. In this hydrogenation reaction with Pd / C as catalyst, 3MdVL was produced but no 3MPD was formed. The 3MdVL was distilled to a purity between 90% and 97%.

[0048] 3.2 gram of the 93 wt% purified 3MdVL was mixed with 720 mg RaNi (Grace 2800) at 150 C, 20 bar hydrogen, and 3 hours and 15 minutes. The final reaction mixture was analyzed by GC. It contained 87.1 wt% of 3MdVL, 10.9 wt% of 3MPD and 1.6 wt% of impurities.

[0049] COMPARATIVE EXPERIMENT

[0050] The same experiment as comparative experiment I, but after the 3 hours and 15 minutes reacting at 150 °C, the temperature was increased to 170 °C for another 6 hours. The reaction mixture was analysed with GC. It contained 35.2 wt% 3MdVL, 58,1 wt%3MPD and 6.7 wt% impurities. COMPARATIVE EXPERIMENT III

[0051] 250 mg of aMVL and 25 mg CuO.Cr2O3 were dissolved in 1 ml THF. Hydrogenation was done at 180 °C, 70 bar hydrogen for 16 hours. The reaction mixture contained 0.2 wt% aMVL, 86.4 wt% 3MdVL , 7.9 wt% 3MPD and 5.5 wt% impurities.

[0052] COMPARATIVE EXPERIMENT IV

[0053] 250 mg of aMVL and 50 mg CuO.Cr2O3 were mixed without a solvent. Hydrogenation was done at 180 C, 70 bar H2 for 16 hours. The reaction mixture contained 66.1 wt% of 3MdVL, 0.2 wt% 3MPD and 33.7 wt% impurities.

[0054] Table 1

[0055] Examples 1-2 reflect the conditions of the one pot hydrogenation of aMVL with RaNi. Comparative experiments l-IV reflect the conditions of the hydrogenation of aMVL into 3MdVL with Pd / C and hydrogenation of 3MdVL into 3MPD with RaNi or a Cu / Cr catalyst. MEVAOOQ1-WO - 8-

Claims

CLAIMS1. Process for the manufacturing of biobased 3-methyl-delta-valerolactone (3MdVL) and 3-methyl-1 ,5-pentanediol (3MPD) in one-pot hydrogenation of anhydromevalonolactone (aMVL) in the presence of a Raney-Nickel catalyst.

2. Process according to claim 1 whereby the hydrogenation occurs without solvent.

3. Process according to any one of the claims 1-2 whereby the hydrogenation occurs at a temperature from 120°C-180°C.

4. Process according to claim 3 whereby the hydrogenation occurs at a temperature from 130°C-170°C.

5. Process according to any one of the claims 1-4 whereby the hydrogenation occurs at a pressure between 15-30 bar.

6. Process according to claim 5 whereby the hydrogenation occurs at a pressure between 18 and 22 bar.

7. Process according to any one of the claims 1-6 whereby the hydrogenation time may vary between 3 and 25 hours.

8. Process according to claims 7 whereby the hydrogenation time may vary between 6 and 24 hours.

9. Process according to any one of the claims 1-8 whereby the ratio (3MdVL) / (3MPD) varies between 20 / 80-80 / 20.

10. Process according to any one of the claims 1-9 whereby the amount of catalyst may vary between 10-35 wt% based on the total weight of aMVL.

11. Process according to any one of the claims 1-10 wherein the hydrogenation temperature varies between 140°C-170°C and whereby the reaction time is between 9-24 hours.

12. Process according to any one of the claims 1-10 wherein the hydrogenation temperature varies between 130°C-150°C, whereby the reaction time is between 3-4 hours.

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