DE3335870A1 - Process for reacting hydrogen fluoride with fatty acid esters - Google Patents

Abstract

There is described a process for reacting hydrogen fluoride with wax, the resulting products, and their use.

Description

Process for the reaction of hydrogen fluoride with

Fatty Acid Esters The present invention relates to a method for the reaction of hydrogen fluoride with fatty acid esters, according to this process produced conversion products as well as their use.

DE-PS 551 787 discloses a process for converting fatty acid glycerides of vegetable and animal origin with hydrogen fluoride known. Be there Triglycerides reacted directly with hydrogen fluoride at temperatures below 100 C. Polymers are obtained as reaction products, with products depending on the duration of the reaction can be obtained with different degrees of polymerization.

The object of the invention is to implement the implementation known per se Transferring hydrogen fluoride to other classes of substances.

Another object of the invention is to find new, technically valuable To provide products that are obtained through such implementation can.

The. Objects are achieved by what is specified in the claims Process or characterized reaction products.

The method according to the invention is based on the generic method and is characterized in that the fatty acid ester is a wax with a melting point Ts <60 C, preferably Ts <40 ° C.

A fatty acid ester is used as the wax in the context of the present invention from a preferably unsaturated fatty acid with a preferably unsaturated one Understood monoalcohol or a mixture of such fatty acid esters.

A preferred variant provides that a fatty acid ester is used Mixture of esters of long-chain carboxylic acids and monoalcohols with a total of 34 until SO carbon atoms set in.

Particularly preferred are fatty acid esters which have an iodine number of below 95, preferably from 30 to 95, in particular 75 to 95. Mixtures such fatty acid esters are commercially available.

The reaction is carried out in particular at temperatures from 0 to 80.degree executed. Although it is also possible to work at atmospheric pressure, it is preferred worked at increased pressure, e.g. at 1.1 to 10 bar.

Different reaction products are obtained depending on how the reaction is carried out.

One type of reaction product is obtained under relatively mild process conditions. In this variant, pressure and temperature are preferred in the lower part the specified area worked. e.g. at 1.1 to 5 bar and / or at 0 up to 30 ° C, it is crucial that in this variant a molar ratio of hydrogen fluoride to Wax from 0.1: 1 to 2: 1, in particular 0.4: 1 to 1.8: 1 is adhered to.

The products of this reaction (hereinafter referred to as adducts) are fluorine containing, waxy liquids, evidently produced by the addition of hydrogen fluoride to the fatty acid esters and their fluorine content depending on the reaction conditions can be varied over a wide range. In very mild conditions, i.e. short Reaction times and / or low temperature and / or low supply of hydrogen fluoride adducts with a low fluorine content or relatively high and low iodine numbers are used Melting point obtained. On the other hand, in not so mild conditions, i.e. longer Reaction times and / or higher temperature and / or higher supply of hydrogen fluoride Adducts with a higher fluorine content or relatively low iodine numbers and a higher melting point obtain. The fluorine content of the adducts is in the range from 0.1 to 4.3 wt.

In principle there are adducts with all iodine numbers between the iodine number of the liquid wax used can be produced down to practically zero. By variation of the fluorine content, the melting point of the adduct can also be varied. In this respect, it is possible to use waxes that are increasingly inert and have a higher melting point which complement the range of conventional waxes and which e.g. as a parting agent component, lubricant or as an additive for lubricant mixtures, can be used in particular as a component for cooling lubricants.

A completely different type of reaction product is obtained when im specified framework is worked under more drastic process conditions. at this variant is in terms of pressure and / or temperature in the upper range, so e.g. worked at 3 to 10 bar and / or 20 to 80 C.

The decisive factor in this variant is that a molar ratio of hydrogen fluoride to wax of 2: 1 to 15: 1, preferably 4: 1 to 10: 1 is observed.

The products of this reaction (hereinafter called sesquimers) are oily products, which (compared to the starting wax) 1.1 to 1.9 times in particular 1.2 to 1.6 times the molar mass and a content of unreacted wax of less than 1% by weight. In the event that the wax is a mixture of fatty acid esters is used, the molecular weight of the sesquimer is the average molecular weight to understand. Surprisingly, the sesquimers are therefore not mixtures of monomers and polymers such as di-, tri- or oligomers with a corresponding average Molar mass. The reaction mechanism and the constitution of the sesquimers are true not yet fully clarified; but it can be regarded as certain that In this implementation, it is not - as in the case of DE-PS 551 787, for example - is a polymerization.

The sesquimers contain only very low amounts, if at all bound fluorine. As a rule, the fluorine content is below 0.1 wt.

Compared to the starting wax, the sesquimers have a considerable amount decreased iodine number, which in a preferably obtained sesquimer in the range from 5 to 20. Further characteristics and spectroscopic data for preferred Sesquimers are given in the examples.

The sesquimers and the adducts are technically valuable products. They find a preferred use in lubricants. Due to good frictional wear values as Sesquimers in particular can achieve high thermal stability as such or as additives in high-quality lubricants e.g. for engines, gears, Refrigerating machines are used, where appropriate on the use of other additives how e.g. EP additives can be dispensed with.

The sesquimers are also called hydraulic fluids and due their thermal stability and their high flash point, especially as heat transfer fluids usable.

The sesquimers in particular are suitable for use in cooling lubricants for machining, separating or abrasive treatment of various materials, preferably of metals.

Cooling lubricants based on chlorofluorocarbons are particularly preferred (HFC). In one variant, such a cooling lubricant consists of 0.5 to 25 wt. preferably 0.5 to 5% by weight of sesquimer and / or adduct to 99.5 to 75% by weight, preferably 99.5 to 95% by weight of a chlorofluorocarbon with 1 or 2 carbon atoms and a boiling point of more than 20 C. In particular, trichloromonofluoromethane, 1,1,2-trichloro-1,2,2-trifluoroethane, 1,1,2,2-tetrachlorodifluoroethane, tetrachloromonofluoroethane and / or trichlorodifluoroethane in question.

It is also possible to use part of the sesquimer or the adduct by the wax used for its production and / or sulfochlorinated or to replace sulfided derivatives of the wax.

Another variant provides for those cases in which the cooling lubricant evaporates too quickly on its own, up to 35% by weight, preferably up to 15% by weight, of HFC due to a toxicologically harmless one that regulates evaporation solvent to replace. Examples are lower aliphatic ketones with 3 to 4 carbon atoms suitable. The solvents that control evaporation usually have a higher value Boiling point than the HFC used. Ethanol, n- and / or are particularly preferred i-propanol.

Another variant provides for the cooling lubricant as a solubilizer to add for the sesquimer or adduct. As a sesquimer or adduct solubilizer well-known, toxicologically harmless solvents come with solubilizing agents Properties in question that can replace up to 10% by weight of the HFC.

A preferred solution provides as a sesquimer or.

To use adduct solubilizers aliphatic hydrocarbons, which can also be used as an evaporation regulator, preferably in a concentration of up to 15 wt. of the PFC, can be used. Appropriate aliphatic ones, for example, are suitable Hydrocarbons or gasoline fractions, e.g. gasoline with a boiling range of 40 - 80 C.

Those hydrocarbons which form an azeotrope with the PFC are preferred able to form. The optimal composition corresponds to the azeotropic composition Concentration used. An addition of n-heptane has proven to be particularly useful exposed.

Another preferred solution provides the sesquimer or adduct solubilizer to select from the group of long-chain aliphatic alcohols, the 16 to 24 Contain carbon atoms and preferably one or more carbon double bonds contain.

Another embodiment of the invention provides the cooling lubricant in addition to add up to 1 total% of the HFC of known corrosion inhibitors. Such corrosion inhibitors for metals such as magnesium, aluminum, titanium, brass, Bronze, steel are commercially available. They are mostly based on compositions the organic compounds with hetero atoms such as sulfur or especially nitrogen contain. Individual compounds or mixtures from the class, for example, have proven themselves Benzothiazoles, e.g., mercaptobenzothiazole, benzimidazoles, e.g., 2-phenylbenzimidazole, Triazoles, e.g. benzotriazoles, tolyltriazoles, oxazolines, e.g. alkyl- and / or hydroxyalkyl-substituted Oxazolines, amides, amines, e.g. tertiary amines, when using corrosion inhibitors One embodiment of the invention provides for up to 10% by weight of the PFC by solubilizing agents to replace the inhibitors. For the selection of the inhibitor solubilizer the same general considerations apply as for the selection of the sesquimer or adduct solubilizer. Preferred solubilizers for both the inhibitor as well as for the sesquimer or adduct are lower aliphatic alcohols with 1 up to 5 carbon atoms. Of these, in particular, ethanol, n- and / or i-propanol are mentioned, which, as already mentioned, can also be used as an evaporation controller can be.

If an addition belongs to several additional types, its maximum is Concentration not to be calculated additively, but depends on the highest Single concentration.

The specified cooling lubricant can be used for machining metals can be applied in all known ways. For example, it can be used as a liquid or can be applied as an aerosol. It can also be applied externally, i.e. be brought to the tool from the outside, as well as internally, i.e. by suitable, feeds provided in the tool itself. The internal application is e.g.

when executing deep bores - or for internal grinding reach. The cooling lubricant can also generally be used for cutting, separating or abrasive treatment of hard materials.

With the use of sesquimers or adducts for cutting, separating or abrasive machining of metals, good results are achieved. So is in Comparison to the use of trichloromonofluoromethane as the sole cooling lubricant a significantly lower energy expenditure for cutting, separating or abrasive Treatment of metals such as magnesium, aluminum, titanium, brass, bronze, steel to be recorded. This observation is particularly evident when More compact pieces of metal, e.g. to be drilled, milled or cut.

Surprisingly, the improvement is particularly noticeable then on when the cooling lubricant is a corrosion inhibitor, preferably based on Contains oxazoline.

In addition, good chip evacuation and built-up edges are ensured are prevented. The cooling and lubricating properties are very good. A comparison the frictional wear values with a commercially available product also show advantages.

Furthermore, surprisingly, there is practically no greasing of the metal surface on what, given the waxy or oil-like character of the added sesquimers or adducts was not to be expected.

Due to the toxicological harmlessness of the cooling lubricant there is also no risk of legally stipulated labor concentrations (MAK-Rerte) are exceeded.

The inventive method for converting hydrogen fluoride can be carried out in both variants preferably in the presence of inert solvents will.

The process for producing the adducts is not very critical and can be used in solvents as diverse as chlorinated hydrocarbons such as carbon tetrachloride, methylene chloride, in chlorofluorocarbons such as 1,1,2-trichloro-1,2,2-trifluoroethane, 1,1,2,2-tetr-achl.ordifluoroethane, in aromatic Solvents such as benzene and in substituted aromatic solvents such as Toluene or xylene can be carried out. But it is also possible without a solvent to work.

The process for making the sesquimers, on the other hand, is strongly influenced by the Affects solvent. Substituted solvents have proven to be excellent solvents aromatic solvents such as toluene and xylene in particular have proven their worth.

The work-up of the reaction products is possible in both process variants uncritical. The adducts can after neutralization and, if appropriate, after concentration filtered off and washed. Adducts with high iodine numbers and sesquimers are used conveniently isolated by removing the solvent. Further known ones Purification stages such as distillation, chromatography or refining can to be connected The following examples describe both Process variants and give characteristic data for adducts produced according to the invention and sesquimers again, Furthermore, in the following examples the composition specified by cooling lubricants containing sesquimers and / or adducts, which have proven themselves in the processing of metals.

All percentages mean 0 by weight. They also mean JZ = Iodine number, S = sesquimer and A = adduct (the following number refers to the corresponding experiment describing the production of the sesquimer or adduct), Ester = wax used, SC = sulfochlorinated, i.e. one made by adding sulfur and chlorine on the double bond of the wax obtained product and Su = a through Addition of sulfur to the double bond of the wax obtained product. It mean furthermore R 11 = trichloromonofluoromethane, R 112 = 1, t, 2,2-tetrachlorodifluoroethane, R 113 = 1,1,2-trichloro-1,2,2-trifluoroethane, R 121 = tetrachloromonofluorethane, R 122 = Trichlorodifluoroethane.

The waxes used and the corrosion inhibitors are commercially available Products. The agent based on triazole is based on a benzotriazole the agent based on oxazoline is an alkyl- and hydroxyalkyl-substituted oxazoline.

BeisDiel 1: Synthesis of the adduct in a 11 stainless steel pressure vessel a solution of the ester (JZ = 82) in xylene was introduced with a stirrer and 6 g Hydrogen fluoride reacted at a temperature of 25 C.

The reaction time, including the post-reaction, was about 5 Hours. After the completion of the reaction, the reaction solution was made with nitrogen rinsed and neutralized with KOH granules. The acid-free product was filtered and freed from solvent in a rotary evaporator. A solid resulted Product.

Information on further reaction conditions and key figures of the obtained Products are shown in Table 1.

Table 1: Production of adducts Attempt ester | Xylene I time i pressure I JZ r m.p.lF content 1 tg 3 1 [g 3 lt hrs. 31 bar lt ec 1 f 3 | ----------- | ------- | -------- | 1.1 1 100 1 500 1 5.5 1 5 131.9152-541 2.54 1.2 300 300 5 4 52.3 1.43 1 1 1 1.3 1 400 1 300 1 5 1 4 167.1125-311 0.66 Example 2: Synthesis of the sesquimer A solution of 1.5 kg of ester (JZ = 82, M = 606 g / mol) in 1.5 1 of xylene and 350 to 380 g of hydrogen fluoride in pressed the reaction vessel. The internal temperature was set to 50 ° C. and the stirrer speed was 200 to 300 rpm. After a reaction time of 5 hours, the mixture was stirred for a further 5 hours and the reaction mixture was worked up by blowing off the unconverted hydrogen fluoride and then flushing it with nitrogen. The neutralization was carried out using solid KF.

Residual acidity was removed with KOH granules. The acid-free obtained Product was filtered and the solvent was stripped off in a rotary evaporator. A golden yellow, viscous oil with the following physical and chemical properties resulted chemical properties: C-bonded fluorine 0.02% by weight hydrolyzable, free Fluorine 0.002 wt. 04 Iodine number 14 Molar mass 790 g / mol Density2 '0.9125 g / cm3 Viscosity 194.4 mm2 / sec.

Neutralization number <0.005 Acid number 1.2 Refractive index 20 1.4945 Flash point according to DIN 51 376 318 eC Boiling point according to DIN 51 751 415 C pour point according to DIN 51 597 - 18 C unreacted ester <1 x IR spectrum wave number (cm) 2935 873 2854 846 1735 818 1611 806 1580 766 1508 720 1458 1172 EXAMPLE 3: Correspondingly Example 2 further sesquimers were obtained; Product features and deviating Reaction conditions are given in Table 2. The determination of the molar mass M was carried out osmometrically in a Knauer vapor pressure osmometer.

Table 2: Production of sesquimers Trial Ester HF Xylene T t JZ M [g] [g] [g] [° C] [Std] [g / mol] 3.1 300 85 300 50 5 11.1 784 3.2 1 300 1 71 1 300 1 47 1 22 1 12.31 792 3.3 1 300 # 62 1 300 1 35 1 6 1 15.61 837 Example 4: In Table 3 compositions according to the invention are given. which can be used as cooling lubricants. Example 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.11 4.12 R11 98.5 49.0 R 112 49.0 70.9 R 113 49.0 49.0 98.5 95.9 64.0 85.5 97.0 94.8 R 121 98.5 R 122 98.3 S2 JZ = 14 1.5 2.0 2.0 1.5 1.5 1.5 1.5 1.5 1.5 3.0 5.0 1.5 i-propanol 27.6 34.5 n-propanol 2.6 Acetone 13.0 Corr. inhibitor Base tert. Amine Corr. inhibitor Based on oxazoline 0.2 0.2 Table 3: continued Example 4.13 4.14 4.15 4.16 4.17 4.18 4.19 4.20 4.21 4.22 4.23 R11 98.5 R 112 93.6 93.6 93.4 R 113 95.7 95.7 95.7 94.6 95.7 91.2 95.7 S2 JZ = 14 0.75 0.75 0.75 1.5 0.75 1.5 0.75 3.0 1.5 1.5 1.5 Ester JZ = 90-80 0.75 Ester JZ = 40 0.75 SC 0.75 2.0 Su 0.75 0.75 Ethanol 3.7 3.6 i-propanol 2.6 2.6 4.9 2.6 2.6 2.6 n-heptane 4.9 4.9 Corr. inhibitor Base triazole 0.2 0.2 0.2 Base oxazoline 0.2 0.2 0.2 Base tertiary amine 0.2 0.2 Table 3: Continuation Example 4.24 4.25 4.26 4.27 4.28 4.29 4.30 R113 98.5 95.0 95.9 95.7 95.7 98.5 98.0 #A 1.3 11.5 # 5.0 11.5 11.5 1 10.5 10.5 A1.2 0.75 S2 0.75 0.5 0.5 Ester JZ = 80-90 0.5 #SC IIII 1 10.5 10.5 # i-propanol I 1 12.6 12.6 12.6 1 # # Corr.-Inhibitor Base Oxazolin ll 1 10.2 10.2 # #

Claims (11)

Claims> Process for converting hydrogen fluoride with fatty acid esters of vegetable or animal origin at temperatures below 100 ° C, characterized in that the fatty acid ester is a wax with a melting point Te <60 ec begins. 2. The method according to claim 1, characterized in that as Fatty acid ester a mixture of esters of long-chain carboxylic acids and monoalcohols starts with a total of 34 to 50 carbon atoms. 3. The method according to any one of the preceding claims, characterized in, that the fatty acid esters have an iodine number of less than 95. 4. The method according to any one of the preceding claims, characterized in that that the reaction is carried out at a temperature of 0 to 80.degree. 5. The method according to any one of the preceding claims, characterized in, that the reaction is carried out under pressure, preferably at 1.1 to 10 bar. 6. The method according to any one of the preceding claims, characterized in, that one hydrogen fluoride and fatty acid ester in a molar ratio of 2: 1 to 15: 1, preferably 4: 1 to 10: 1 is used. 7. The method according to any one of the preceding claims, characterized in, that the reaction is carried out in an inert solvent. 8. Reaction products of hydrogen fluoride and a wax with a Melting point T, <60 C, obtainable by one of the preceding processes, characterized by a (compared to the starting wax) 1.1 to 1.9 times, in particular 1.2 to 1.6 times average molar mass and a content of unreacted wax of less than 1 wt. 9. Products according to claim 8, characterized by an iodine number of 5 to 20. 10. Addition product of hydrogen fluoride and a wax with a Melting point T. <60 ec, obtainable by a process corresponding to one of Claims 1 to 5 and / or 7, characterized by a fluorine content of 0.1 to 4.3 wt. 11. Use of products according to one of claims 8 to 10 in lubricants, especially in cooling lubricants for cutting, separating or abrasive treatment of metals.