Method for producing long-chain linear alkenes

Abstract

The present invention relates to the synthesis of unsubstituted linear terminal C 10 ~C 16 Alkenes to Linear Internal C 10 ~C 16 The present invention relates to a process for producing long-chain linear alkenes, which provides alkenes. The present invention relates to a linear and internal C 10 ~C 16 The method for obtaining alkenes includes the following steps: (i) Unsubstituted linear terminal C 10 ~C 16 Mixing the alkene with a supported or unsupported metal precursor; (ii) heating the mixture obtained in step (i) at a temperature between 150° C. and 300° C. to isolate catalytic metal atoms in situ from the metal precursor; It consists of the following steps, and its features are: The metal precursor is an unsubstituted linear terminal C 10 ~C 16 The preferred amount is less than 100 ppm by weight relative to the alkene.

Description

[Technical field]

[0001] The present invention relates to a process for the production of long chain linear alkenes which are useful as lubricants and in paper industry applications. [Background technology]

[0002] Unsubstituted long-chain internal alkenes are essential compounds for industrially produced open-chain compounds, but their synthesis is costly and their subsequent transformations are limited. This is because the most direct and simplest method for synthesizing internal alkenes, i.e., transferring a double bond from an inexpensive and widely available terminal alkene to a desired internal position to obtain a clean internal alkene, has not yet been solved at either the research or industrial level, and therefore the technology of transferring a double bond in an alkene has not yet met the need to produce simple internal alkenes.

[0003] Currently, isomerization of unsubstituted long-chain alkenes is carried out in industry using solid bases at temperatures of 200-450°C in a continuous stream, generally with conversions of 80-90% to produce a mixture of alkenes and some branched products (Patent Document 1, Patent Document 2, Patent Document 3). This mixture of different internal components will give the desired migration position (2, 3, 4, etc.), but in addition to the corresponding cis and trans stereoisomers of each alkene (see comments below), the final mixture may contain 2(n-1) isomers for a given alkene with n alkyl chains. The above mentioned patents (see, for example, US Pat. No. 5,399,633) do not describe the final composition in detail. As an example, only the isomerization of short chain gaseous alkenes such as 1-butene has been described so far, resulting in a cis / trans ratio of 1:2 in 2-butene at 80% conversion, which means a low yield of about 50% pure trans-2-butene. This conversion is not acceptable for many applications such as the corresponding unsubstituted long chain alkenes lubricants and paper sizing agents. For example, long chain lubricants require a lack of branching in the final product and a conversion of at least greater than 95% (starting with less than 5% terminal olefins). Otherwise, the lubricating properties are lost and the desired final product solidifies and is no longer liquid.

[0004] Current double bond migration processes for petroleum-derived terminal alkenes combine both processes by utilizing the production of fluid terminal alkenes, called normal alpha-olefin (NAO) technology. No examples of unsubstituted long-chain terminal alkenes, i.e., terminal alkenes with 8 or more carbons that would be considered linear long-chain alkenes, have been described so far (see, for example, U.S. Patent No. 5,333,636).

[0005] Furthermore, to date, terminal olefins from the NAO process require additional purification (by distillation) before entering the transfer process, otherwise the catalyst will rapidly deactivate (US Pat. No. 3,723,564).

[0006] Furthermore, the migration of the double bonds of unsubstituted long chain terminal alkenes derived from petrochemicals is not an optimized process, requiring expensive catalysts, energy intensive processes, poor conversion, and resulting in product mixtures containing large amounts of branched and saturated alkenes that are detrimental to the final mixture.

[0007] Isomerization of terminal olefins to internal olefins has also been described using a fluidized solid catalyst with silica-alumina as a catalyst, with a conversion rate of about 98% at 75-150°C (Patent Document 5). The results show that the distribution of the isomers is quite broad, and the process requires circulation of the product mixture for typically 4 hours to achieve a process yield of 20 kilograms of product per kilogram of catalyst, which is insufficient for flexible, efficient and inexpensive industrial production.

[0008] There have also been studies using solid-supported metals as catalysts for transferring double bonds containing long-chain linear terminal alkenes (see Patent Documents 6 and 7). However, these solid catalysts only provide partial conversion (about 68%) using a mixture of metals or aldehydes as additives in amounts of several thousand ppm, making them unsuitable for industrial purposes.

[0009] The migration of double bonds in terminal alkenes has also been studied using homogeneous catalysts in solution. These catalysts can be basic or acidic.

[0010] For the isomerization of simple alkenes, KOH and NaOH in combination with iron (Non-Patent Document 1) or alumina (Patent Documents 8 and 9) have been used as homogeneous catalysts in basic solution. However, these bases usually require the use of very large amounts (often stoichiometric), resulting in long reaction times, caustic residue generation, and often incomplete conversion. Furthermore, these strong bases are not particularly suitable for applications of long-chain linear internal alkenes derived from petroleum, because the alkene is unfavorable to subsequent acid-catalyzed reactions, such as hydroaddition, Friedel-Crafts, or epoxidation reactions, if the base remains in the final mixture.

[0011] Soluble acidic catalysts based on metal complexes have been more studied than basic catalysts, and these systems have shown higher conversions and selectivities (up to 99% in both cases) than solid catalysts, opening up new avenues for the synthesis of internal alkenes in the laboratory. However, they have significant obstacles to industrial implementation, such as stoichiometric additives, large amounts of solvents, and unacceptable metal catalyst amounts (usually 0.5-10 mol%), making them economically unacceptable for commercial industrial processes (Non-Patent Document 2, Non-Patent Document 3, Non-Patent Document 4, Non-Patent Document 5, Non-Patent Document 6). There are examples of Ru catalysts that are soluble in very small amounts for certain long-chain alkenes, but in some cases this requires a carbon monoxide atmosphere, as well as the use of very expensive and toxic carbon monoxide complexes, making these catalyst systems not only economically unattractive, but also dangerous and undesirable in terms of the possibility and safety of continued use (Patent Document 10, Patent Document 11).

[0012] Therefore, to achieve industrial scale production, a method that significantly improves the yield and selectivity of the transfer of terminal double bonds to long chain internal bonds is desirable. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] U.S. Pat. No. 3,723,564 [Patent Document 2] U.S. Patent No. 6,281,404 [Patent Document 3] U.S. Patent No. 5,801,293 [Patent Document 4] U.S. Patent No. 8,324,423 [Patent Document 5] US Patent Application Publication No. 2005 / 0070747 [Patent Document 6] U.S. Pat. No. 3,352,939 [Patent Document 7] U.S. Pat. No. 3,409,702 [Patent Document 8] European Patent Application Publication No. 0027939 [Patent Document 9] German Patent Application Publication No. 2137024 [Patent Document 10] International Publication No. 2014 / 1508211 [Patent Document 11] US Patent No. 9708236 [Non-patent literature]

[0014] [Non-Patent Document 1] ChemSusChem,2012,Vol.5,p.734-739 [Non-Patent Document 2] Science,2019,Vol.363,p.391-396 [Non-Patent Document 3] Chem.Cat.Chem.,2017,Vol.9,p.3849-3859 [Non-Patent Document 4] Chem.Rev.,2003,Vol.103,p.27-51 [Non-Patent Document 5] J.Organomet.Chem.,1975,Vol.86,C17 [Non-Patent Document 6] J.Mol.Cat.,1981,Vol.11,p.293-300 Summary of the Invention [Means for solving the problem]

[0015] The present invention relates to linear and internal C 10 ~C 16 The method for obtaining alkenes includes the following steps: (i) Unsubstituted linear terminal C 10 ~C 16 mixing the alkene with a supported or unsupported metal precursor; (ii) heating the mixture obtained in step (i) at a temperature between 150° C. and 300° C. to isolate catalytic metal atoms in situ from the metal precursors; It consists of steps, and its features are: The metal precursor is an unsubstituted linear terminal C 10 ~C 16 The preferred amount is less than 100 ppm by weight relative to the alkene. Effect of the Invention

[0016] The process of the present invention allows the preparation of unsubstituted, unbranched, long-chain linear internal alkenes having 10-16 carbon atoms, preferably 12-14 carbon atoms, by migration of the double bond in the corresponding terminal alkene, catalyzed by homeopathic amounts (less than 100 ppm) of metals from groups VIII and IX, supported or unsupported, without external reducing agents such as H2 or aldehydes, and without pre-reduced soluble catalysts such as hydrides or carbon monoxide. It is also preferred that the process be carried out without a solvent. 10 ~C 16 Alkenes are well suited for isomerization due to their unique hydrophobicity and density properties, and the reaction is more efficient in both cases due to less catalyst poisoning compared to lower or higher carbon number alkanes. [Brief description of the drawings]

[0017] [Figure 1] This is a 1H-NMR spectrum of 1-dodecene (A) and the reaction product (B) after reacting with 0.0005 mol% Ru(C4H8)2 (COD) for 4.5 hours. [Diagram 2] This is a 1H-NMR spectrum of 1-tetradecene (A) and the reaction product (B) after reacting with 0.0005 mol% Ru(C4H8)2 (COD) for 4.5 hours. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] In another embodiment, the present invention relates to the aforementioned process, wherein steps (i) and (ii) are carried out in the absence of a solvent.

[0019] In another embodiment, the present invention relates to a process as described above, further comprising an isolation step (iii) for isolating the product obtained in step (ii), which in the present invention consists of recovering the final product, since the removal of additives or by-products is not necessary.

[0020] In another embodiment, the present invention relates to the above-mentioned method, further comprising the step (i) of: 10 ~C 16 The alkene is an unsubstituted linear terminal C 12 ~C 14 More preferably, the unsubstituted linear terminal C 10 ~C 16 The alkene is selected from 1-dodecene and 1-tetradecene.

[0021] In another embodiment, the present invention relates to the aforementioned method, wherein the metal precursor of step (i) is selected from salts, complexes, nanoparticles, and macroscopic forms of metals from groups VIII and IX of the periodic table or mixtures thereof.

[0022] In another embodiment, the present invention relates to the aforementioned process, wherein the metal of the metal precursor in step (i) is from Group VIII of the periodic table, preferably the metal of the metal precursor in step (i) is from Group VIII of the periodic table and is selected from Fe, Ru, Os, and mixtures thereof. In another embodiment, the present invention relates to the aforementioned process, wherein the metal of the metal precursor in step (i) is from Group IX of the periodic table, preferably, the metal of the metal precursor in step (i) is from Group IX of the periodic table and is selected from Co, Rh, Ir, and mixtures thereof. In another embodiment, the present invention relates to the aforementioned process, wherein the metal of the metal precursor in step (i) is selected from Fe, Ru, Os, Co, Rh, Ir, and combinations thereof, preferably selected from Fe, Ru, and mixtures thereof, more preferably the metal precursor in step (i) is Ru.

[0023] In another embodiment, the present invention relates to the aforementioned method, wherein the metal of the metal precursor in step (i) is Ru(III), Ru(II), or Ru(0). In another embodiment, the present invention relates to a method as defined above, wherein the metal precursor is Ru3(CO) 12 , RuCl3, Ru(C4H8)2COD, Ru(PPh)3C l2 , Ru nanoparticles in colloidal form, and Ru nanoparticles as pure metal. Throughout the present invention, nanoparticles (NP) in colloidal form refer to surfactant-stabilized nanoparticles. Examples include, inter alia, carboxylic acids, carbenes, thiols, and ammonium salts. Nanoparticles (NP) as pure metals refer to nanoparticles that must be supported.

[0024] In another embodiment, the present invention relates to a method as defined above, wherein the metal precursor is supported on an inorganic oxide, preferably the inorganic oxide is selected from alumina, titania, silica, zinc oxide, zirconium oxide, nanoceria, activated carbon, and / or combinations thereof.

[0025] In another embodiment, the present invention relates to a method as defined above, wherein the metal precursor is a Ru salt which has optionally been reduced.

[0026] In another embodiment, the present invention relates to a method as defined above, wherein the metal precursor is supported on activated carbon.

[0027] In another embodiment, the present invention relates to the above-mentioned method, further comprising the step (i) of: 10 ~C 16 The alkene is present in an amount between 10,000 and 100,000,000 equivalents relative to the metal precursor, preferably between 1,000,000 and 10,000,000 equivalents relative to the metal precursor, more preferably between 2,000,000 and 5,000,000 equivalents relative to the metal precursor.

[0028] In another embodiment, the present invention relates to a method as defined above, wherein the metal precursor is an unsubstituted linear terminal C 10 ~C 16 Between 1 ppm and 100 ppm by weight of alkene, preferably unsubstituted linear terminal C 10 ~C 16 Between 1 ppm and 50 ppm by weight of alkene, more preferably unsubstituted linear terminal C 10 ~C 16 It is used in an amount between 1 and 10 ppm by weight relative to the alkene.

[0029] In another embodiment, the present invention relates to a process as defined above, wherein step (ii) of the process is carried out in a simple stirred batch reactor or in a continuous flow or fixed bed stirred tank reactor, preferably in a simple stirred batch reactor. Throughout the present invention, the term "batch" refers to a fixed batch reactor.

[0030] In another embodiment, the present invention relates to a process as defined above, wherein the temperature in step (ii) is between 200°C and 250°C, more preferably at a temperature of 200°C.

[0031] In another embodiment, the present invention relates to a process as defined above, wherein step (ii) is carried out at a pressure between 1 bar and 20 bar, preferably at 1 bar.

[0032] In another embodiment, the present invention relates to a method as defined above, wherein step (ii) is carried out under an inert or ambient atmosphere, preferably under an inert nitrogen, helium or argon atmosphere, more preferably under a nitrogen atmosphere. Throughout the present invention, the term "ambient atmosphere" refers to carrying out the method in the same as an outdoor environment, but not under an inert atmosphere.

[0033] In another embodiment, the present invention relates to a process as defined above, wherein step (ii) is carried out in the presence of an organic solvent, preferably in the presence of an aromatic solvent.

[0034] In another embodiment, the present invention relates to a process as defined above, wherein the reaction time of step (ii) is between 0.5 and 72 hours, preferably between 1 and 24 hours.

[0035] In another embodiment, the present invention relates to a method as defined above, wherein the unsubstituted linear terminal C 10 ~C 16 The alkene is 1-dodecene, the metal precursor in step (i) is Ru, and the temperature in step (ii) is 200°C.

[0036] In another embodiment, the present invention relates to a method as defined above, wherein the unsubstituted linear terminal C 10 ~C 16 The alkene is 1-dodecene, the metal precursor in step (i) is Ru, the temperature in step (ii) is 200° C., and step (ii) is carried out under an inert nitrogen atmosphere.

[0037] In another embodiment, the present invention relates to a method as defined above, wherein the unsubstituted linear terminal C 10 ~C 16 The alkene is 1-dodecene, the metal precursor in step (i) is Ru, the temperature in step (ii) is 200° C., step (ii) is carried out under an inert nitrogen atmosphere, the reaction time is 4.5 hours, and the reaction pressure is 1 bar.

[0038] In another embodiment, the present invention relates to a method as defined above, wherein the unsubstituted linear terminal C 10 ~C 16 The alkene is 1-tetradecene and the metal precursor in step (i) is Ru.

[0039] In another embodiment, the present invention relates to a method as defined above, wherein the unsubstituted linear terminal C 10 ~C 16 The alkene is 1-tetradecene, the metal precursor in step (i) is Ru, and the temperature in step (ii) is 200°C.

[0040] In another embodiment, the present invention relates to a method as defined above, wherein the unsubstituted linear terminal C 10 ~C 16 The alkene is 1-tetradecene, the metal precursor in step (i) is Ru, the temperature in step (ii) is 200° C., step (ii) is carried out under an inert nitrogen atmosphere, the reaction time is 5 hours, and the reaction pressure is 1 bar.

[0041] Throughout the present invention, the term "unsubstituted linear terminal C 10 ~C 16 The term "alkene" refers to an alkene having 10 to 16 carbon atoms, no branching or substitution, and a terminal double bond. Examples include 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, and 1-hexadecene.

[0042] The term "metal precursor" refers to solid-supported or non-solid-supported salts, complexes, nanoparticles, and macroscopic forms of metals that form highly active isolated metal atoms in situ and can be converted to unsubstituted linear terminal C groups without the use of solvents. 10 ~C 16 They are useful as catalysts for the transfer of double bonds in alkenes. The solid supports are inorganic oxides such as alumina, zeolites, silica, etc. Examples are metals from groups VIII and IX of the periodic table, such as Fe, Ru, Os, Co, Rh, and Ir, among others.

[0043] The in situ formed catalysts used in the process of the present invention are based on the use of very small amounts, typically parts per million (ppm).

[0044] Unsubstituted linear internal C obtained by the method of the present invention 10 ~C 16 The structural properties of alkenes are useful in the lubricant and paper processing industries.

[0045] Throughout the specification and claims, the word "comprise" and its variations are not intended to exclude other technical features, additives, ingredients or steps. Other objects, advantages and features of the present invention will be understood in part by those skilled in the art from both the description and the embodiments of the present invention. The following examples and drawings are provided for illustrative purposes and are not intended to limit the present invention.

[0046] The invention will now be illustrated by tests carried out by the inventors which demonstrate the effectiveness of the product of the invention.

[0047] Table 1 shows the results of using 1-dodecene with Ru-type catalyst. The double bond migration is achieved by using only 5 ppm by weight (input 6) of Ru catalyst, and although the reaction time is long (20 hours), the conversion rate exceeds 95%. This linear terminal olefin with an alkyl chain has a boiling point of 200°C or higher and good thermal stability, so it can be converted to an internal alkene at a temperature of 150°C or higher, improving the conversion rate in a shorter time. Table 1 shows that at 200°C, after 4.5 hours the isomerization continues with a conversion of over 97%. It should be noted that in this case, depending on the amount of catalyst, the internal alkene mixture is different. For example, with 1 ppm by weight of catalyst, 72% 2-dodecene and 18% other internal alkenes, and with 5 ppm by weight, 26% 2-dodecene. This result is consistent for the starting material (1-dodecene) across several commercial companies. In any case, the final linear internal alkene mixture is consistent for a given amount of catalyst.

[0048] [ka]

[0049] [Table 1]

[0050] Table 2 shows the results for 1-tetradecene at reaction temperatures of 150°C and 200°C. As evaluated above for 1-dodecene, at 200°C, the conversion exceeded 97% after 5 hours with 5 ppm Ru by weight, and higher conversions were obtained at shorter times. It must be taken into account that a conversion exceeding 95% is difficult to achieve in any industrial process and is highly beneficial for the end use of the product.

[0051] [ka]

[0052] [Table 2] EXAMPLES

[0053] Double bond migration of 1-dodecene using the catalyst Ru(C4H8)2COD at 5 wtppm: 1-Dodecene (27 g) was placed in a 50 ml flask equipped with a magnetic stirrer and Ru(methallyl)2COD catalyst (0.0005 mol%) was added. The flask was closed with a septum, a nitrogen atmosphere was created, and the flask was placed in a preheated oil bath at 200 °C and stirred with a magnetic stirrer for the designated reaction time. Aliquots were taken from the reaction mixture and the reaction was monitored over time using GC and NMR. A stock solution of Ru catalyst in dichloromethane (which evaporates during the reaction) was considered to have been prepared since the amount used was too small to be weighed. To prepare these solutions, a volumetric flask was used with dichloromethane as the solvent. For GC analysis, 5.6 μL of the reaction mixture was diluted with 1 mL of ethyl acetate. For NMR analysis, 20 mg of the reaction mixture was dissolved in deuterated chloroform (CDCl3 signal: singlet, 7.26 ppm) and 15 mg of 1,2-dichloroethane (signal: singlet, 3.73 ppm) was added as an internal standard to calculate the reaction conversion. Figure 1 shows how the starting terminal alkene disappears and the desired product appears. EXAMPLES

[0054] Method for double bond migration of 1-tetradecene using the catalyst Ru(C4H8)2COD at 5 ppm by weight: 1-Tetradecene (32 g) was placed in a 50 ml flask equipped with a magnetic stirrer and Ru(methallyl)2COD catalyst (0.0005 mol%) was added. The flask was closed with a septum, a nitrogen atmosphere was created, and the flask was placed in a preheated oil bath at 200 °C and stirred with a magnetic stirrer for the designated reaction time. Aliquots were taken from the reaction mixture and the reaction was monitored over time using GC and NMR. Stock solutions of Ru catalyst in dichloromethane (which evaporates during the reaction) were considered to have been prepared since the amount used was too small to be weighed. To prepare these solutions, a volumetric flask was used with dichloromethane as the solvent. For CG analysis, 5.6 μL of the reaction mixture was diluted with 1 mL of ethyl acetate. For NMR analysis, 20 mg of the reaction mixture was dissolved in deuterated chloroform (CDCl3 signal: singlet, 7.26 ppm) and 15 mg of 1,2-dichloroethane (signal: singlet, 3.73 ppm) was added as an internal standard for calculating the reaction conversion. Figure 2 shows the disappearance of the starting terminal alkene and the appearance of the desired product. EXAMPLES

[0055] A method for migration of the double bond of 1-dodecene in a stirred reactor using a solid Ru-on-silica catalyst: A solid Ru-on-silica catalyst, which was made by impregnating large surface area silica with RuCl3 to a final Ru content of 1 wt%, was placed in a 50 ml flask equipped with a magnetic stirrer at 0.001 mol% relative to 1-dodecene (27 g), followed by 1-dodecene (27 g). The flask was closed with a septum, a nitrogen atmosphere was created, and the flask was placed in an oil bath preheated to 200 °C and stirred with a magnetic stirrer for the specified reaction time. A supernatant sample was taken and the reaction was monitored over time using GC and NMR. For NMR analysis, 20 mg of the supernatant was dissolved in deuterated chloroform (CDCl3 signal: singlet, 7.26 ppm) and 15 mg of 1,2-dichloroethane (signal: singlet, 3.73 ppm) was added as an internal standard to calculate the reaction conversion.

Claims

1. Internal and linear C １０ ~C １６ A method for obtaining an alkene, i) non-replaceable linear terminal C １０ ~C １６ Mix the alkene with a supported or unsupported metal precursor, ii) heating the mixture obtained in step (i) at a temperature of 150°C to 300°C to isolate metal atoms that act as a catalyst in situ from the metal precursor, wherein the metal precursor uses an amount less than 100 ppm by weight with respect to the unsubstituted linear terminal C １０ -C １６ alkene, steps (i) and (ii) are carried out without a solvent, and the metal of the metal precursor in step (i) is Ru.

2. The unsubstituted linear terminal C of the step (i) １０ ~C １６ The alkene is the unsubstituted linear terminal C １２ ~C １４ The method according to claim 1, characterized in that it comprises an alkene of

3. The unsubstituted linear terminal C of the step (i) １２ ~C １４ The method according to claim 1 or 2, characterized in that the alkene of the alkene is selected from 1-dodecene and 1-tetradecene.

4. wherein the metal precursor is Ru ３ (CO) １２ , RuCl ３ , Ru(C ４ H ８ ), ２ COD, Ru(PPh) ３ C ｌ２ , the method according to claim 1, characterized in that it is selected from Ru nanoparticles in colloidal form and Ru nanoparticles as pure metal

5. The method according to claim 1, wherein the metal precursor is supported on an inorganic oxide.

6. The unsubstituted linear terminal C of the step (i) １０ ~C １６ The method according to claim 1, characterized in that the alkene is present between 10,000 equivalents and 100,000,000 equivalents relative to the metal precursor.

7. wherein the metal precursor is a non-substituted linear terminal C １０ to C １６ The method according to claim 1, characterized in that it is used in an amount between 1 ppm and 100 ppm by weight with respect to the alkene.

8. The method according to claim 1, wherein step (ii) is carried out in a batch reactor equipped with a simple stirring device, or a tank-type continuous reactor stirred in a continuous flow or fixed bed.

9. The method according to claim 1, wherein the temperature of step (i) is between 200°C and 250°C.

10. The method according to claim 1, wherein step (ii) is carried out at a pressure between 1 bar and 20 bar.

11. The method according to claim 1, wherein step (ii) is carried out under an inert atmosphere.

12. The method according to claim 1, wherein the reaction time of step (ii) is between 0.5 hours and 72 hours.

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