Patentamt à JEuropâischesEuropean Patent Office ® Publication number: 0 061395 Office européen des brevets B1

© EUROPEAN PATENT SPECIFICATION

(§) Dateof publication of patent spécification: 24.10.84 © Int. Cl.3: C 07 C 69/14, C 07 C 69/16, C 07 C 67/00 (Zp^ Application number: 82400486.5 ® Dateoffiling: 17.03.82

® Préparation of ethyl acétate.

(30) Priority: 17.03.81 US 244572 (73) Proprietor: EASTMAN KODAK COMPANY 17.03.8T US 244578 343 State Street Rochester New York 14650 (US)

@ Date of publication of application: 29.09.82 Bulletin 82/39 ® Inventor: Larkins, Thomas Hassell, Jr. Rt.8, 4408 Beechcliff Drive Kingsport Tennessee 37664 (US) Publication of the grant of the patent: Inventor: Tennant, Brent Alan 24.10.84 Bulletin 84/43 3601 Clearwater Drive Kingsport Tennessee 37664 (US) Inventor: Pond, David Martin (84) Designated Contracting States: 1333 Dupont Drive BE DEFRGB ITNL Kingsport Tennessee 37664 (US) Inventor: Glenn, Thomas Jackson 5024 Ross Road Références cited: Kingsport Tennessee 37664 (US) EP-A-0 034 062 US-A-3 957 827 US-A-4221 918 (7Ï) Représentative: Parent, Yves et al CD Kodak-Pathé Département des Brevets et Licences 30, rue des Vignerons B.P. 60 10 F-94302 Vincennes Cedex (FR) O) co

5 o o Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall Ùm be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been m paid. (Art. 99(1) European patent convention). Courier Press, Leamington Spa, England. especially 130 to 150°C, and 500 to 1500 psig (3550 to 10445 kPa). When the material is a This invention relates to a process for the mixture of acetic anhydride and ethylidene preparation of ethyl acetate by hydrogenating diacetate, preferred temperatures and pressures acetic anhydride or mixtures of acetic an- are 170 to 250°C, especially 200 to 225°C, hydride and ethylidene diacetate. and 2000 to 2500 psig (13895 to 17340 kPa). The hydrogenation of acetic anhydride using When a substantial amount of ethylidene a nickel catalyst in the presence of a strong acid, diacetate is fed to the reaction with the acetic such as hydrochloric acid, hydrofluoric acid, or anhydride, for example 50:50 weight mixtures, methane sulfonic acid, is disclosed in U.S. the ethylidene diacetate resists hydrogenation Patent 4,221,918. The products obtained are and retards the hydrogenation of the acetic reported to be ethylidene diacetate, acetic acid anhydride. Consequently, relatively severe and, when hydrochloric acid was the acid used, reaction conditions are required to hydro- 1-chloroethyl acetate. When ethyl acetate is the genate such mixtures to ethyl acetate when desired product, this prior art process is imprac- only Raney nickel is used in the reaction. Much tical. The process of this invention provides a milder reaction conditions can be used to hydro- very effective method of making ethyl acetate. genate such mixtures to ethyl acetate if an In accordance with this invention acetic an- organic sulfonic acid is used in the reaction hydride or a mixture of acetic anhydride and medium. The organic sulfonic acid enables the ethylidene diacetate is hydrogenated with use of milder, more economical reaction con- Raney nickel as the hydrogenation catalyst to ditions and it results in higher conversions of form ethyl acetate. acetic anhydride and ethylidene diacetate to The feed to the hydrogenation reactor can, if ethyl acetate. desired, contain, in addition to acetic anhydride The amount of organic sulfonic acid that is and/or ethylidene diacetate, an inert solvent used is within the range of 0.1 to 3 weight such as. acetic acid. The acetic acid in the percent, based on the total weight of acetic product from the reaction can be converted to anhydride and ethylidene diacetate. The pre- methyl acetate and used in the production of ferred amount is 0.5 to 1.5 weight percent. Of acetic anhydride. the many organic sulfonic acids that can be Acetic anhydride containing little if any used, the lower alkyl and aryl sulfonic acids are ethylidene diacetate, e.g., up to about 10 preferred. The most preferred are methane- weight percent, can be readily hydrogenated to sulfonic acid and p-toluenesulfonic acid produce ethyl acetate in good product yields because of their relatively low cost. and space-time yields. However, the presence When an organic sulfonic acid is used in the of larger amounts of ethylidene diacetate hydrogenation process, the reaction tem- inhibits the conversion of acetic anhydride to perature can be in the range of 130°C to products and thus, the use of more severe 175°C, and the reaction pressure can be in the reaction conditions or an organic sulfonic acid is range of 500 to 3000 psig (3550 to 20790 necessary to satisfactorily hydrogenate mixtures kPa). of acetic anhydride and ethylidene diacetate to The process of the invention may be carried form ethyl acetate. out as a batch operation, or more suitably, as a The concentration of the Raney nickel that is continuous process wherein acetic anhydride or used is in the range of 0.1 to 10 weight percent, mixtures of acetic anhydride and ethylidene based on the acetic anhydride and, when diacetate are continuously fed to an autoclave present, ethylidene diacetate. Catalyst concen- and reaction mixture containing the desired trations (same basis) of 0.5 to 2.5 weight products are continuously removed either as percent will most often be used. liquid or as a vapor. Unreacted materials and co- The temperature for the reaction is in the product acetic acid may be removed from the range of 100 to 250°C, although at the higher reaction mixture after removal from the auto- temperatures ethyl acetate decomposition can clave by distillation and recycled to the auto- be a problem. Pressures (total reaction clave. pressure) in the range of 500 to 5000 psig The process of the invention is further illus- (3550 to 3,4590 kPa) may be used, although trated by the following examples. the use of pressures in excess of 2500 psig (17340 kPa) normally is not advantageous. The Examples 1-18 preferred temperatures and pressures vary Acetic anhydride (100 g) and mixtures of depending on whether the material being hydro- acetic anhydride (50 g) and ethylidene diace- genated consists primarily of acetic anhydride tate (50 g) were hydrogenated in the presence or consists of a mixture of acetic anhydride and of varying amounts of Raney nickel using ethylidene diacetate, e.g. mixtures of acetic different temperatures and total autoclave anhydride and ethylidene diacetate in weight pressures. The material hydrogenated in ratios of about 4:1 to 1:4. When the material Examples 1-7 was acetic anhydride and in being hydrogenated consists primarily of acetic Examples 8-18 it was a 50-50 mixture of anhydride, the preferred temperatures and acetic anhydride and ethylidene diacetate. The pressures are in the range of 130 to 200°C, acetic anhydride, ethylidene diacetate (when used) and Raney nickel catalyst were loaded the preset value during the reaction by adding into a 300 ml stainless steel, rocking autoclave. hydrogen gas at the same rate at which it was The autoclave was purged with 100 psig (739 consumed by the reactants. When the pre- kPa) hydrogen gas pressure at room tem- determined reaction time was completed the perature and then the gas was vented. The autoclave was cooled by a stream of cold air. internal pressure of the autoclave was increased After the gas was vented from the autoclave the to 10 psig (172 kPa) by adding hydrogen gas at reaction product was analyzed by gas room temperature. The autoclave was sealed chromatographic methods. and heated and rocked until reaction Table I shows the reaction temperature (°C) temperature was reached, at which time addi- and pressure in psig and (kPa), the amount of tional hydrogen gas was added to increase the catalyst (cat., g) charged, the amount (in moles) autoclave internal pressure to the predeter- of ethyl acetate (EA) produced, the percent of mined value. The time at which the autoclave acetic anhydride (AczO) and ethylidene diace- internal pressure reached the predetermined, tate (EDA) consumed (cons.) and the product value was taken as the start of the reaction yield (PY, percent of theory) and space-time time. A reaction time of 2 hours was used in yields (STY, in grams/liter liquid-hour) for ethyl Examples 1-16 and 1 hour in Examples 17 acetate. and 18. Reaction pressure was maintained at

Example 19 psig (13895 kPa) in the presence of 2.0 g of Using the procedure described for the pre- Raney nickel. Six runs were carried out using ceding examples, a mixture of 75 g acetic the same catalyst. After each run the liquid anhydride and 75 g ethylidene diacetate was product was pumped from the autoclave hydrogenated for 1 hour at 200°C and 2000 through a metal frit so as to leave the catalyst in the autoclave. Fresh acetic anhydride and anhydride and ethylidene diacetate consumed ethylidene diacetate were then pumped into the and the product yield and spacetime yield for autoclave and the next run was carried out. ethyl acetate for each of the six runs. The overall Table II shows the amount (moles) of ethyl average for each of the results measured is acetate produced, the percent of the acetic shown at the bottom of the table.

Examples 20-36 Table III shows the temperature (°C) and A mixture of acetic anhydride (50 g) and pressure in psig and (kPa), the amount of nickel ethylidene diacetate (50 g) was hydrogenated in catalyst (cat., g) and p-toluenesulfonic acid the presence of varying amounts of Raney nickel (PTSA, g) charged, the amount (in moles) of (Examples 20-28) and Raney nickel promoted ethyl acetate (EA) produced, the percent of with p-toluenesulfonic acid (Examples 29-36) acetic anhydride (AczO) and ethylidene diace- using different temperatures and total auto- tate (EDA) consumed (cons.) and the Product clave pressures. The reaction procedure and yield (PY, percent of theory) and space-time equipment were identical to Examples 1-18. yields (STY, in grams/liter liquid-hour) for ethyl The reaction time for Examples 20-28 was 2 acetate. hours and 1 hour for Examples 29-36. Table III illustrates the advantages which 150°C using a catalyst concentration of 0.5 to result from the use of the organic sulfonic acid. 2.5 percent, by weight, of acetic anhydride. In Example 14 almost all of the ethylidene 5. The process according to claim 1 wherein diacetate was consumed whereas in Example 6, a mixture of acetic anhydride and ethylidene using significantly more severe conditions but in diacetate is hydrogenated at a pressure of 2000 the absence of an organic sulfonic acid, only to 2500 psig (13895 to 17340 kPa) and a tem- 17.6% of the ethylidene diacetate was perature of 170 to 250°C. consumed. 6. The process according to claim 1 wherein a mixture of acetic anhydride and ethylidene diacetate is hydrogenated at a pressure of 500 to 3000 psig (3550 to 20790 kPa) and at a 1. Catalytic process for the preparation of temperature of 130°C to 175°C and an organic ethyl acetate characterized by hydrogenating sulfonic acid is used with the Raney nickel in the acetic anhydride or a mixture of acetic hydrogenation reaction. anhydride and ethylidene diacetate by using 7. The process according to claim 6 wherein Raney nickel as a catalyst for the process. the concentration of Raney nickel is 0.1 to 10 2..The process according to claim 1 wherein percent, by weight, of acetic anhydride and the reaction pressure is 500 to 5000 psig ethylidene diacetate and the concentration of (3550 to 34590 kPa) and the reaction tem- organic sulfonic acid is 0.1 to 3 percent, by perature is 100° to 250°C. weight, of acetic anhydride and ethylidene 3. The process according to claim 2 wherein diacetate. the catalyst concentration is 0.1 to 10 percent, 8. The process according to claim 7 wherein by weight, of acetic anhydride or a mixture of the organic sulfonic acid in methanesulfonic acetic anhydride and ethylidene diacetate. acid or p-toluenesulfonic acid. 4. The process according to claim 1 wherein 9. The process according to claim 8 wherein acetic anhydride is hydrogenated at 130°C to the pressure is 500 to 1500 psig (3550 to 10445 kPa), the temperature is 140°C to Konzentration an organischer Sulfonsäure 0,5 160°C, the concentration of Raney nickel is 0.5 bis 1,5 Gew.-% beträgt. to 2.5 weight percent and the concentration of organic sulfonic acid is 0.5 to 1.5 weight percent. 1. Procédé catalytique pour la préparation d'acétate d'éthyle, caractérisé en ce qu'on hydrogène de l'anhydride acétique ou un 1. Katalytisches Verfahren zur Herstellung mélange d'anhydride acétique et de diacétate von Ethylacetat, gekennzeichnet durch d'éthylidène en utilisant du nickel de Raney Hydrieren von Essigsäureanhydrid oder einer comme catalyseur du procédé. Mischung von Essigsäureanhydrid und 2. Procédé conforme à la revendication 1, Ethylidendiacetat unter Verwendung von dans lequel la pression de la réaction est de 500 Raney-Nickel als einen Katalysator für das Ver- à 5000 psig (3550 à 34 590 kPa) et la tem- fahren. pérature de la réaction est de 100°C à 250°C. 2. Verfahren nach Anspruch 1, dadurch ge- 3. Procédé conforme à la revendication 2, kennzeichnet, daß der Reaktionsdruck bei 3550 dans lequel la concentration du catalyseur est bis 34590 kPa und die Reaktionstemperatur bei de 0,1 à 10% en masse, par rapport à 100° bis 250°C liegen. l'anhydride acétique ou au mélange d'anhydride 3. Verfahren nach Anspruch 2, dadurch ge- acétique et de diacétate d'éthylidène. kennzeichnet, daß die Katalysatorkonzentration 4. Procédé conforme à la revendication 1, bei 0,1 bis 10 Gew.-%, bezogen auf Essig- dans lequel on hydrogène l'anhydride acétique à säureanhydrid oder eine Mischung von Essig- 130°C à 150°C en utilisant une concentration säureanhydrid und Ethylidendiacetat liegt. de catalyseur de 0,5 à 2,5% en masse, par 4. Verfahren nach Anspruch 1, dadurch ge- rapport à l'anhydride acétique. kennzeichnet, daß Essigsäureanhydrid bei 5. Procédé conforme à la revendication 1, 130°C bis 150°C unter Verwendung einer dans lequel on hydrogène un mélange Katalysatorkonzentration von 0,5 bis 2,5 Gew.- d'anhydride acétique et de diacétate %, bezogen auf Essigsäureanhydrid hydriert d'éthylidène à une pression de 2000 à 2500 wird. psig (13895 à 17340 kPa) et à une tem- 5. Verfahren nach Anspruch 1, dadurch ge- pérature de 170°C à 250°C. kennzeichnet, daß eine Mischung aus Essig- 6. Procédé conforme à la revendication 1, säureanhydrid und Ethylidendiacetat bei einem dans lequel on hydrogène un mélange Druck von 13895 bis 17340 kPa und einer d'anhydride acétique et de diacétate Temperatur von 170 bis 250°C hydriert wird. d'éthylidène à une pression de 500 à 3000 psig 6. Verfahren nach Anspruch 1, dadurch ge- (3550 à 20790 kPa) et à une température de kennzeichnet, daß eine Mischung aus Essig- 130°C à 175°C et on utilise un acide säureanhydrid und Ethylidendiacetat bei einem sulfonique organique avec le nickel de Raney Druck von 3550 bis 20790 kPa und einer Tem- dans la réaction d'hydrogénation. peratur von 130°C bis 175°C hydriert wird, und 7. Procédé conforme à la revendication 6, daß zur Durchführung der Hydrierungsreaktion dans lequel la concentration de nickel de Raney mit dem Raney-Nickel eine organische Sulfon- est de 0,1 à 10% en masse par rapport à säure verwendet wird. l'anhydride acétique et au diacétate 7. Verfahren nach Anspruch 6, dadurch ge- d'éthylidène et la concentration de l'acide kennzeichnet, daß die Konzentration an Raney- sulfonique organique est de 0,1 à 3% en masse, Nickel bei 0,1 bis 10 Gew.-%, bezogen auf par' rapport à l'anhydride acétique et au Essigsäureanhydrid und Ethylidendiacetat, und diacétate d'éthylidène. die Konzentration an organischer Sulfonsäure 8. Procédé conforme à la revendication 7, bei 0,1 bis 3 Gew.-%, bezogen auf Essigsäure- dans lequel l'acide sulfonique organique est anhydrid und Ethylidendiacetat liegt. l'acide méthanesulfonique ou l'acide p-toluène- 8. Verfahren nach Anspruch 7, dadurch ge- sulfonique. kennzeichnet, daß die organische Sulfonsäure 9. Procédé conforme à la revendication 8, Methansulfonsäure oder p-Toluolsulfonsäure dans lequel la pression est de 500 à 1500 psig ist. (3550 à 10445 kPa), la température est de 9. Verfahren nach Anspruch 8, dadurch ge- 140°C à 160°C, la concentration en nickel de kennzeichnet, daß der Druck bei 3550 bis Raney est de 0,5 à 2,5% en masse et la concen- 10445 kPa und die Temperatur bei 140°C bis tration en acide sulfonique organique est de 0,5 160°C liegt und daß die Konzentration an à 1,5% en masse. Raney-Nickel 0,5 bis 2,5 Gew.-% und die