SK108298A3 - Method for the preparation of cyclic carbonates - Google Patents

Abstract

Cyclic carbonates of the general formula (I), wherein R a R' are the same or different and are H, alkyl, alkenyl or haloalkyl with 1 to 20 carbon in the molecule, cycloalkyl and its halo derivative with 5 to 12 carbon, aryl, alkylaryl and their halo derivatives and nitro derivatives, are prepared by addition of carbon dioxide to at least one epoxycompound of the general formula (II), wherein R and R' have mentioned meaning, at the temperature 50 to 180 °C, by synergism of aprotic alkaline solvent and at least one catalyst or catalytic system, whereby partial pressure of carbon dioxide in reaction medium is 20 kPa to 3.5 MPa and total pressure of reaction medium is maximum 6 MPa. Reaction medium is water free or the content of the water is mostly 0.8 % by weight/epoxyreactants. Catalyst or catalytic system contains in the molecule on average 0.5 to 4 of halide anions or ligands and at least the part of catalyst is recycled.

Description

Process for preparing cyclic carbonates

Technical field

The present invention relates to a process for the preparation of cyclic carbonates under mild reaction conditions allowing to achieve high selectivity for cyclic carbonates, using technically available and readily regenerable catalysts, respectively. catalytic systems.

BACKGROUND OF THE INVENTION

Alkylene carbonates or cyclic esters of carbonic acid and alpha, beta-diols, but also alkenyl carbonates as well as ether carbonates can be produced by the reaction of alpha, beta-unsaturated or alpha, gamma-diols with phosgene or with alkyl chloroformates [Nemirovskij J .: J. prakt . Chem. 28, 439 (1883); Vorländer D .: Hun. 280, 186 (1894); Allpress C.F., Maw V .: J. Chem. Soc. 125. 225g (1924)]. Also by the reaction of alkyl chloroformates with alkali metal glyconates, as well as by the action of concentrated sodium carbonate solutions with 1,2- and 1,3-dichlorohydrin [German Pat. 516,281 (1931); France. pat. 1,139,206 (1957)]. Said processes are resource-intensive and, in particular, produce low-value to waste by-products, burdening waste water, which need to be disposed of with considerable cost. In this regard, the transesterification of dialkyl carbonates by diols is technically more interesting [Morgan M. S., Gretcher L.H .:

J. Am. Chem. Soc. 68, 781 (1946)], but the process requires the availability of some dialkyl carbonate [Sarel S. et al: J. Org. Chem. 24 (12), 1873 (1959)]. In the case of addition of trichloroacetic acid to the oxirane, respectively. alkyloxirates [US 2,784,201 (1957)], in turn, the need for corrosive and technically demanding trichloroacetic acid. However, the addition of carbon dioxide epoxides [nem. pat. 740,366 (1943); U.S. Pat. No. 2,667,497 (1954), 1,758,946, 2,773,881 (1956) and 2,873,282 (1956), with alkali metal hydroxides on activated carbon, anhydrous calcium and magnesium halides known as catalysts. Furthermore, pyridine, acridine and some aliphatic tertiary amines have proven to be effective catalysts, and on such catalysts at a temperature of 180 to 200 ° C and a pressure of 50 to 100 atm the yield of alkylene carbonates reaches 97 to 98%. 2,733,070 (1956)] and the use of quaternary halides of ammonium, such as (C ₆ H ₅₎ NBR, and the. Since, however, also form undesirable by-polymeric products, for the suppression of the formation is suggested [US 2,773,881 (1956) and No. 2,873,282 (1959)] to apply a large excess of 50-500% by weight of carbon dioxide [Hechler G .: Chem., 43, 16903, (1971); Levin SZ et al: Neftechimija H. (4), 573 (1962), Nomura R. et al., J. Org. Chem., 45, 3735 (1980)]. However, a substantial excess of carbon dioxide can suppress the formation of only some by-products. Thus, it is not surprising that other catalysts for the addition of carbon dioxide to oxirane, methyloxirane and other epoxy compounds are sought, such as alkylchloroantimone compounds [Gorski R., Kliniec J .: Przemysl Chemicz. 70 / 9,392 (1991); CH 620434 (1976); Polish Pat. 138, 902 (1983); U.S. Pat. No. 2,994704 (1961)], cerium nitrates [U.S. Pat. No. 5,179,214 (1993)], chromium carbonylporphirins [U.S. Pat. No. 4,663,467 (1987)], transition metal phthalocyanines [U.S. Pat. No. 5,283,356 (1994)], based on quaternary transition metal complexes IV.b or Vb of the Lewis base periodic system group [EP 069 494 A1 (1982)] as well as transition metal halides, but also alkali metal, zinc and nickel halides in combination with an aprotic base - e.g. Ν, Ν-dimethylformamide [Bobylev LI et al .: Neftechimija 36 / 3,209 (1996)]. The reaction temperature is most often 180 to 200 ° C and the pressure above 5 MPa, or the reaction temperatures are even below 70 ° C, but the reaction time is at least 24 h. In some known experimental results, although the high pressure did not correlate with the synthesis of cyclic carbonates in high yield, but as the catalyst has also generally changed, the anomaly is clearly attributed to the type of catalyst or catalyst system. Thus, the advantages of the known cyclic carbonate preparation processes take advantage of the problems and anomalies of the processes solved by the method of the present invention.

SUMMARY OF THE INVENTION

According to the present invention, a process for the preparation of cyclic carbonates of the general formula o o o

II II (R) —C — C— (R j.

in which R and R 'are the same or different and are hydrogen, alkyl, alkenyl or haloalkyl of 1 to 20 carbon atoms, cycloalkyl and its 5 to 12 carbon atoms, aryl or alkylaryl and their halogens; carbons of 6 to 12, etheralkyl of 2 to 12 carbons and their halogenated and nitroderivatives, by addition of carbon dioxide to at least one epoxy compound of the general formula, at a temperature of SO to 180 ° C, in association with an aprotic basic medium and at least one catalyst and / or catalyst system , selected from quaternary ammonium halides and bases, urea salts, halides: alkaline earth, zinc, cadmium, aluminum, iron, cobalt, nickel, chromium, molybdenum, thallium, antimony, zirconium, hafnium, cerium, niobium, organometallic compounds , such as metallospirins, phthalocyanines of iron, chromium, manganese, titanium, vanadium, zirconium, nickel cadmium, zinc, hydroxyaluminium phthalocyanine, chloralumine phthalocyanine, organotetraalkylphosphonium tin halide complexes such that the partial pressure of carbon dioxide in the reaction medium is 20 kPa to 3.5 MPa and the total reaction medium pressure is at most 6 MPa, the reaction medium being free of water or water not more than 0.8% by weight, calculated on the weight of epoxy reactants or a mixture of epoxy reactants and solvent products, the catalyst and / or catalyst system containing on average 0,5 to 4 halide anions and / or ligands and at least a part of the catalyst and / or catalytic system is recycled.

An advantage of the process of the present invention is the high selectivity of addition of carbon dioxide with epoxy compounds to cyclic carbonates, at a minimum partial pressure of carbon dioxide. Possibility to utilize unrefined carbon dioxide, including inert natural gas or other gases containing carbon dioxide, as well as low sensitivity of catalysts or catalytic systems to conventional catalytic poisons. Then lower operating costs, in particular lower energy consumption, as well as substantially lower investment costs for equipment.

Known catalysts and catalyst systems are suitable for carrying out the process of the invention, metal compounds containing halide anions or ligands in the molecule are most suitable.

As the carbon dioxide-containing gas, in addition to the pure carbon dioxide, not only conventional commercial technical carbon dioxide, but even inert natural gas containing at least 50% by volume of water can be used. carbon dioxide or exhaled carbon dioxide. It is possible to use released carbon dioxide from fermentation processes, even from limestone, dolomite and magnesite burning. However, it is advisable to take care not only of "dedusting", minimizing the nitrogen and oxygen content, but especially of the water vapor, which would react with the epoxy compounds by a competitive reaction.

A sufficient carbon dioxide partial pressure of at least 20 kPa is required for sufficient propulsion power and hence sufficient reaction rate. However, at substantially higher partial pressure of the oxide to the desired cyclic carbonates. When assessing the effect of the total pressure, the vapor pressure at the reaction temperature must be taken into account in particular for ethylene oxide and propylene oxide. A good aid for selecting a suitable partial pressure of carbon dioxide is the vapor pressure dependence of ethylene oxide, propylene oxide vapor and epichlorohydrin, shown in FIG. Obviously, in a continuous process of production, whether ethylene carbonate or propylene carbonate, or both, at the same time, with a constant lack of ethylene oxide or propylene oxide in the reaction medium, their vapor pressure is actually lower.

In particular, care must be taken to avoid or only to a limited extent enter aprotic compounds such as water, alcohols, acids, amines, etc., whether with reactants or with a catalyst. Therefore, it is desirable to dry the epoxy compounds as well as carbon dioxide containing gas. In the case of catalysts, preference is given to non-hydrated forms. Although the process according to the invention can also be carried out at a content of over 0.8% by weight. water / epoxy compound in the reaction medium, even a polar catalyst may even be better reflected in the conversion of the epoxy compound, but the selectivity to cyclic carbonates decreases markedly.

Catalysts, respectively. catalyst systems, on average per molecule, should contain 0.5 to 4 halide anions and / or ligands, most preferably 1 to 2 halide anions and / or ligands per molecule. Due to the relatively good stability of the catalysts or catalyst system, it is advisable to recirculate them. Generally, technically demanding regeneration is not necessary and only the compensation of the losses with the fresh catalyst can be sufficient.

Further data on carrying out the process according to the invention as well as other advantages are apparent from the examples.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

To a stainless steel autoclave of a volume of 125 cm ^3, equipped with a propeller mixer (1000 FIG / min), was weighed 15.0 g Ν, Ν-dimethylformamide containing 0.05% by weight. water, 15 g propylene oxide with 0.013 wt. water and various types and quantities of cobalt salts, taking care of their solubility in the prepared batch. After the autoclave was closed and the air was removed, carbon dioxide was passed to a pressure of 2.5 MPa. To this end, the contents of the autoclave are heated to 120 ° C with constant stirring and maintained at an accuracy of ± 2 ° C for 3 h. When the total pressure in the autoclave drops below 2 MPa, it is pressurized with carbon dioxide. The autoclave is then cooled, the product is removed, weighed and analyzed by GC.

The results obtained with the different types and amounts of catalyst are summarized in Tab. First

Example 2

The procedure is analogous to Example 1, but comparing the halide activities of the different catalysts at 0.0195 mol / mol propylene oxide. The results are summarized in Tab. Second

Table 1

catalyst number product [G] conversion AFTER [%] Selectivity to propylene carbonate [%] kind of [G] number mol / mol PO * CoCl ₂ .6H ₂ O 0.1 0.0016 33.5 83.4 53.3 CoCl ₂ .6H ₂ O 0.6 0.0098 35.5 98.9 66.3 CoCl ₂ .6H ₂ O 1.2 0.0195 41.2 99.3 93.3 CoCl ₂ 1.2 0.0195 41.4 99.9 97.2 COC1 ₂ .6H ₂ O 2.4 0.0391 31.6 99.5 35.7 FeCl ₃ .6H ₂ O 1.44 0.0206 38.6 100 77.1 FeCl ₃ .6H ₂ O 2.88 0.0413 36.5 100 59.9  PO = propylene oxide Table 2 catalyst Total Conversion PO Weight Selectivity to Product [g] r% i propylene carbonate [%] NiCl ₂ .6H ₂ O 38,40 99.5 87.8 SnCl ₂ .2H ₂ O 39.20 94.9 71.2 CuC1 ₂ 2H ₂ O 26.80 38.9 20,05 CuC1 ₂ 28.2 41.9 23.3 CaCl ₂ 39.8 99.2 82.5 FeCl ₃ 37.2 99.6 71.3 ZnCl ₂ 38.8 99.98 90.6 NaCl 29.70 44,21 0.1 CoCO ₃ 27.1 30.9 0.1 (CH ₃ COO) ₂ Co 30.3 48.6 0.2 (HCOO) ₂ Ca 28.0 50.1 0.5

Example 3

The procedure is similar to that in Example 1, except that 15.0 g of Ν, im-dimethylformamide containing 0.29% by weight are used for each experiment. water, 15 g propylene oxide with 0.013 wt. water, 0.82 g of dry CaCl ₂ , initial pressure at temperature instead of 2.0 MPa, and the effect of temperature in isochronous (3 h) experiments was investigated. Thus, at 70, 120 and 150 ° C, the conversion of propylene oxide reaches 41.5.99.2 and 93.6% and the selectivity to propylene carbonate is 0.2.84.5 and 81%, respectively.

Example 4

The procedure is analogous to Example 3, except that 15 g of triethylamine with an addition of 0.04% by weight of water are used instead of Ν, Ν-dimethylformamide. and instead of 0.8 g CaCl ₂ , only 0.3 g but 0.6 g of chromium tetraporphyrin chloride was used. At an initial pressure of 2 MPa of carbon dioxide and not exceeding 3 MPa, while decreasing to 1.2 to 2 MPa, the carbon dioxide was pressurized to 3 MPa. At a temperature of 120 ± 2 ° C for 3 h the conversion of propylene oxide reached 100% and the selectivity to prooylene carbonate was 94.5%. However, at a total pressure of 6 to 9 MPa, the conversion of propylene oxide is also practically 100%, but the selectivity to propylene carbonar is only 74 to 76%, the remainder being mainly propylene glycol and oligomers.

Table 3

epoxy (Epoxy compound) Maintained total pressure [MPa] conversion epoxy compounds [%] Selectivity of converted epoxy compound to cyclic carbonate [%] propylene oxide 6-8 100 62 propylene oxide 2-3 100 92 epichlorohydrin 6-8 100 57 epichlorohydrin 1-2 100 89 butadiénmonoxid 6-8 100 60 3,4-epoxy-1-butene 1-1,8 100 94 glycidylvinyléter 6-8 97 59 epoxycyklopentén 1-1.4 96 95 glycidylvinyléter 0.8-1.2 96 91 cyclohexene 1.8-2.2 94 93 oktadecénoxid (1,2-Epoxyoctadecane) 6-8 98 58 oktadecénoxid (1,2-Epoxyoctadecane) 0.3 - 0.7 94 95 glycidylalkohol 7-9 100 29 glycidylalkohol 1.5-2.5 100 72 butylene 7-9 100 58 butylene 1-2 100 92 Ethylene oxide 7-9 100 54 Ethylene oxide 2-3 100 96

Example S

15 g of N, N-dimethylformamide, 5 g of triisobutylamine, 1 g of triphenylantimmonium bromide, 0.1 g of cobalt bromide and 15 g of epoxide are weighed into the autoclave specified in Example 1. After removal of air, carbon dioxide was introduced. Maintain the reaction temperature at 120 ± 2 ° C and time 180 min. In each experiment, the total pressure and the type of epoxide vary. The content of cyclic carbonates formed is determined by GC or HPLC. The dependence of the conversion and the selectivity of the individual epoxides on the corresponding cyclic carbonates on the total pressure during the reaction of carbon dioxide with the epoxy compound is evident from the results in Tab. Third

Example 6

10 g of Ν, Ν-dimethylformamide are added to the autoclave specified in Example 1 with a water admixture of 0.28% by weight. 5 g of formamide with 0.11 wt. water, various amounts of catalyst, respectively. 15 g of ethylene oxide with an admixture of 0.06 wt. % water or a mixture of ethylene oxide with propylene oxide with an admixture of 0.013 wt. water. It is further fed natural carbon dioxide (inert gas) of the composition (in vol.%): CO 2 = 91.82, N ₂ = 4.96, CH 4 = 3.07, 0.11, ethane, propane = 0.03 , n-butane = 0.01 and admixtures of hydrogen sulfide and carbonyl sulfide. The reaction is carried out at different total pressure, which is maintained by introducing fresh inert natural gas. The reaction temperature is 110 ± 3 ° C and time 180 min. Further reaction conditions and the achieved results of the conversion of alkylene oxides as well as the selectivity to ethylene carbonate and / or propylene carbonate are summarized in Tab. The temperature dependence of the vapor pressure of ethylene oxide, propylene oxide and epichlorohydrin is shown graphically in FIG. First

Table 4

alkylene [G] catalyst Max. overall pressure [MPa] conversion alkylene- oxides [%] selectivity on the cyclic carbonates [%] type (g) % wt. alkylene oxides propylene oxide (15) CaCl ₂ (0.82) 5.47 1.4 100 95 propylene oxide (15) CaCl ₂ (0.82) 5.47 2.2 100 84 propylene oxide (15) CaCl ₂ (0.82) 5.47 4.3 100 75 propylene oxide (10) + ethylene oxide (5) CaCl ₂ (0.82) 5.47 1.4 100 96 propylene oxide (10) + ethylene oxide (5) CaCl ₂ (0.82) 5.47 6 100 68 ethylene oxide (15) CaCl ₂ (0.82) 5.47 3 100 94 ethylene oxide (10) + propylene oxide (5) CaCl ₂ (0.82) 5.47 8 100 63 propylene oxide (15) FeCl ₃ (0.82) 5.47 1 100 82 propylene oxide (15) FeCl ₃ (0.82) 5.47 3 100 72 propylene oxide (15) FeCl ₃ .3H ₂ O (1,44) 9.6 1 100 79 propylene oxide (15) FeCl ₃ .3H ₂ O (1,44) 9.6 4 100 62 propylene oxide (15) FeCl ₃ .3H ₂ O (1,44) 9.6 5 100 51 ethylene oxide (15) FeCl ₃ .3H ₂ O (1,44) 9.6 2.5 100 92 ethylene oxide (15) FeCl ₃ .3H ₂ O (1,44) 9.6 8 100 54 ethylene oxide (15) Bu ₃ SnJ (0.5) 3.3 2.5 98 95 ethylene oxide (15) Bu ₃ SnJ (0.5) 3.3 7.8 98 57 ethylene oxide (15) Bu ₃ PJ (0.6) 4.0 2.5 96 98 ethylene oxide (15) Bu ₃ PJ (0.8) 4.0 7.5 99 58 ethylene oxide (15) Bu ₃ SnCl (0.9) 6.0 2.5 65 94 ethylene oxide (15) Bu ₃ SnCl (0.9) 6.0 7.5 69 74 ethylene oxide (15) CoBr ₂ (0.4) 2.7 2.5 99 96 ethylene oxide (15) CoBr ₂ (0.4) 2.7 6.8 100 62 propylene oxide (15) (CH ₃ ) ₃ SbBr ₂ (0.8) 5.3 2.0 100 88 propylene oxide (15) (CH ₃ ) ₃ SbBr ₂ (0.8) 5.3 6.0 100 64 ethylene oxide (15) chromium (5,10,15,20-tetrapolylporphyrinate chromium (0,8) 5.3 2.5 85 89 ethylene oxide (15) Chromium (5,10,15,20-tetrapolylporphyrinate) (0,8) 5.3 6.0 89 59

Example 7

Using dry calcium chloride in an amount of 0.82 g for each experiment, 15 g of N, N-dimethylformamide and 15 g of propylene oxide specified in Example 6, following the procedure of Example 6, at a reaction time and a total pressure of max. 3.5 MPa investigates the effect of temperature on propylene oxide conversion and selectivity to propylene carbonate at 70 ± 2 ° C, 120 ± 2 ° C and 150 ± 2 ° C. The conversion of propylene oxide is 42%, 100% and 94%. The selectivity to propylene cyanobonate was 19.6%, 84% and 82%, respectively.

Again at a temperature of 120 ± 2 ° C, with the same amount of dry calcium chloride of 0,82 g in each experiment and max. The pressure of 3.5 MPa was monitored for the effect of the amount of Ν, Ν-dimethylformamide at a reaction time of 3 h, using 4.4 g, 15 g and 30 g of Ν, Ν-dimethylformamide. The conversion of propylene oxide reached 84.5%, 99.8% and 93.9%. Selectivity to propylene carbonate 64.5%, 84% and 62%. The remainder to 100% are mainly propylene glycol and propylene oxide oligomers, respectively. propylene glycols.

Example 8

At the bottom of the column, respectively. of a stainless steel absorber, filled to a height of 800 cm with a mixture of Ν, Ν-dimethylformamide and propylene carbonate in a weight ratio of 1; 1 and 1 wt. cobalt bromide calculated on propylene carbonate, at a total pressure of 1100 ± 20 kPa and a temperature of 120 ± 3 ° C to the bottom, propylene oxide is metered in at a rate of 0.40 dm ³ per dm ³ reaction volume per hour while simultaneously feeding dry technical carbon dioxide %, 1 wt. maintaining said pressure of 1100 ± 20 kPa. At the top of the absorber, in which propylene oxide is mainly reacted with carbon dioxide, the crude reaction product is removed, from which unconverted propylene oxide, Ν, Ν-dimethylformamide and propylene carbonate are separated by rectification. The remainder of the rectification column containing practically cobalt compounds, in particular cobalt bromide, propylene carbonate, propylene glycol to polypropylene glycol, and the addition of Ν, im-dimethylformamide, after addition of the additional Ν, Ν-dimethylformamide, recovered mainly by re-rectification, . The conversion of propylene oxide is 88 to 92% and the selectivity to propylene carbonate is 90 to 93%.

Example 9

The procedure is analogous to Example 8, but the working pressure is maintained at 2400 ± 50 kPa. The conversion of propylene oxide is 90 to 93% and the selectivity to propylene carbonate is 82 to 87%.

Example 10

The procedure is analogous to Example 8, except that instead of propylene oxide, 3,4-epoxy-1-butene is injected into the absorber, the first loading of the absorber being only Ν, Ν-dimethylformamide containing 1 wt. In addition to the regenerated catalyst and part of the Ν, dim-dimethylformamide, the heavy organic residue from the boiling point of the rectification column is returned to the regenerated catalyst in the cobalt bromide bromide process and only in the next run of the unsaturated cyclic carbonate production process. The conversion of 3,4-epoxy-1-butene is 82 to 86% and the selectivity to the corresponding unsaturated cyclic carbonate is 88 to 88%.

Industrial usability

The process according to the invention is particularly useful in the chemical industry and, in the future, in other sectors, not only for the production of valuable organic intermediates, solvents, comonomers, but also for the utilization of increasingly problematic carbon dioxide.

Claims (6)

A process for the preparation of cyclic carbonates of the general formula "wherein R and R 'are the same or different and represent hydrogen, alkyl, alkenyl or haloalkyl of 1 to 20 carbons, cycloalkyl and their 5 to 12 carbohydrate derivatives, aryl , alkylaryl and their halogenated derivatives having a carbon number of 6 to 12, etheralkyls having a carbon number of 2 to 12 and their halogenated derivatives and nitro derivatives, by addition of carbon dioxide to at least one epoxy compound of the formula ^nm at 50 to 180 ° C, in association with an aprotic base medium and one catalyst and / or catalytic system selected from quaternary ammonium salt and base halides, urea salts, halides: alkaline earth, zinc, cadmium, aluminum, iron, cobalt, nickel, chromium, molybdenum, thallium, antimony, zirconium, hafnium, niobium , cerium, organometallic compounds of transition metals such as metallphorphyrins, iron phthalocyanines , chromium, manganese, titanium, vanadium, antimony, zirconium, nickel, cadmium, zinc, hydroxyaluminium phthalocyanine, chloraluminium phthalocyanine, organotetraalkylphosphonium tin halide complexes, characterized in that the partial pressure of carbon dioxide in the reaction medium is up to 20 and a pressure of a reaction medium of not more than 6 MPa, the reaction medium being free of water or a water content of not more than 0,8% by weight, calculated on the weight of epoxyreactant or mixture of epoxyreactants with solvent, the catalyst and / or The halide anions and / or ligands and at least a portion of the catalyst and / or catalyst system are recycled. The process according to claim 1, characterized in that the partial pressure of carbon dioxide in the reaction medium is 0.1 to 3 MPa and the total pressure of the reaction medium is 0.15 to 4 MPa. A process according to claim 1 or 2, characterized in that the catalyst in the reaction medium is expressed in wt. % of the cation and / or the central atom per epoxy reactant or epoxy reactants is 0.01 to 3 wt. A process according to claims 1 to 3, characterized in that the solvent is synergistically effective with the catalyst, forming a catalytic system for the selective addition of the epoxy compound with carbon dioxide. Preparation process according to claims 1 to 4, characterized in that the catalyst and / or catalytic system is at least 1/3 homogeneous in one phase with the liquid reaction medium. 6. A process according to any one of claims 1 to 6, wherein the carbon dioxide donor is a gas selected from pure carbon dioxide, an inert natural gas predominantly carbon dioxide, and an exhaled gas predominantly carbon dioxide.