Патент USA US2411802код для вставки
Patented Nov. 26, 1946 _ 2,411,802’ ,7 , c, . 4 , STATE s2,411,802PATENT oFFICE, F AMINE REACTION , ' PURIFICATION 0 MIXTURES ' ' ions. F. Olin, Grosse Ile, Mich., assignor to , Sharnles, Chemicals Ina,v Bhiladelphia, Pa, a _ corporation of-Delaware No Drawing. ApplicationiMay 5, 1944, Serial No. 534,353 - G-Claims, (01. 260-585) The present invention. pertainstothe puri?ca- ' tion ofv crude reaction mixtures resulting from ammonationereduction of, aliphatic aldehydes. or ketones by reaction thereof with ammonia or amines, and hydrogen in the presence of a hy drogenation catalyst. Amination reactions of this general type are well-known in thear-t, and thereafter removed by distillation from the re sulting mixture, the operations of separating the respective amines from each other and from im purities is. greatly facilitated. While I do not wish to belimited by any theoretical reasoning concerning- results attained by the. practice'iof the.‘ invention, itis believed that the treatment ofuthe, crude reaction mixture by an inorganic have been performed both in the liquid and in the vapor phase, as illustrated?‘respectively by base results ire-reactions by which certain-con‘ stituents of the amine-containing reaction'mlx-: volume 172, page 223, and the copendingiappli their conversion into=non-volatile, water-soluble; the article by- Mignonac in. “Comptes Rendus,” 10 ture undergoa chemical change which'resultsi in cation of John F. Olin- & James F. >McKenna, salts, and that the removal of‘ these constituents in the form of‘ an aqueous solution permits the - .While the selective. production of mono-, di remaining constituents of the reaction mixture andtri-alkyl aminesmay, ‘to’ a large’ extent, be 15 to .be separated'from each other with greater Serial Number 428,548,‘_?led~January 28, 1942. controlled by appropriate control of the“ pro portions of reactants employed, it ‘is inevitable that,‘ in a process of this kind; a mixtureof the _ facility. » The basic treatment ‘also’ serves to - liberate the desired. amines from chemical com-' bination in other constituents of the mixture, three amines will .be“ obtained'in' use of ammonia suchas carbamates and imines and thus to im v20 as the aminating-agentyor a mixture of‘ di-_ prove the yield‘ while facilitating ei?cient dis and, tri-alkyl amines obtained in‘ cases in which tillation. When ‘reaction ~mixtures containing a mono-aliphaticfamine is used 'as the aminat- _ carbamates have been distilled, this has resulted ing agent. In the majority'of cases of use of in plugging distillation equipment and‘ also in these amines, the user wishes to employ one of inefficient separation of the amines from each the three amines resulting from the reaction to 25 other. By the preliminary treatment of the the virtual exclusion of ‘the other two. It isv also‘ present invention, .both of ‘these di?iculties. are necessary that-the amines or mixture of: amines obtained from the reaction be separated'from The process of the present invention may be ac , other contaminating;impurities,’ such as nitriles, complished either by batch or continuous opera carbamates, imines, ‘carbon dioxide, ammonia, 30 tion. ~ If it is accomplished by batch operation, aldehydes or ketones, alcohols, etc. The removal the crude amine-containing reaction mixture of certain of these impurities presents a problem, (after removal of ?xed gases, if desired) may be not only because of the fact that the impuri mixed with an aqueous basic solution for a suffi ties are undesirable in the ?nished products, but cient" length of time to effect solution in’ the also because of the fact that the presence of- the 35 aqueous phase of reaction'products of'the'base impurities in the reaction mixture renders, the upon constituents of the reaction mixture. This problem of separation'of the amines from each may be accomplished at ‘atmospheric or superother more di?icult. Whilethe invention may be atmospheric pressure, but I prefer to operate at avoided- ‘ '1 ' ‘ v applied in puri?cation of reaction mixtures ob super-atmospheric pressure, since, by so operat tained by ammonation-reduction of either alde ing, the reaction mixture may be maintained in hydes or ketones regardless of carbon content, it liquid phase at elevated temperatures, and the is.‘ especially, recommended’ for treatment of such use of elevated temperatures facilitates the rapid mixtures obtained from aldehydes. Problemsen completion of the reaction by which impurities countered, in puri?cation of amine-containingre which react with the base are converted into action mixtures from ammonation-reduction of 45 non-volatile water-soluble salts. In' some cases, aldehydes containing from two to six carbon ' the amine-containing reaction mixture will con atoms can be solved with particular advantageby practice of the invention. Ketones of from three to six carbon atoms are also within the. preferred range of the invention. a - The present invention restslupon the discovery that, when reaction mixtures such as those dis-_ I V thoroughly .mixed with an cussed, above are 50 tain, a sui?cient amount of water to dissolve the added base, and in such case the base may be‘ added in solid form. After the desired_ contact between the crude reaction mixture and the basic solution is accom plished, the constituents-of the reaction mixture which are notconverted into non-volatile com aqueousisolution of an inorganic base, and the pounds; bit tteatmentwith. the. base. are. removed amines ‘contained in the reaction mixture, are 5,5 2,411,802 3 from the aqueous phase by distillation. This may be accomplished by fractional distillation from the aqueous phase; 1. e., by distilling and ‘separately condensing and collecting the sepa drogen through a heated reaction tube was ?rst vented, through a column carrying an ammonia re?ux, to remove hydrogen and most of the am monia of the reaction mixture. 120 grams of ?ake sodium hydroxide were added to 938.5 grams of the residual crude reaction mixture, contain rate constituents of the reaction mixture; or it may be accomplished by distilling overhead all of the constituents of the mixture resulting from ing the three ethyl amines and various impurities. the treatment with the basic solution which are The resulting mixture was shaken vigorously, more volatile than the basic solution itself, and thereafter subjecting the mixture of organic con 10 causing the added sodium hydroxide to dissolve in the water contained in the crude reaction mix stituents so obtained in the distillate to a sep ture. The resulting mixture was then fraction arate fractionation by distillation. ally distilled, with the result that 359 grams of The present invention may be very effectively monoethyl amine, 139-grams of diethyl amine and practiced in a continuous manner by mixing the 230 grams of wet triethyl amine (consisting of an crude amine reaction mixture with the aqueous basic solution during continuous flow of the crude :- azeotropic mixture of triethyl amine and water) were obtained.v reaction mixture, and subjecting the resulting mixture formed by addition of the base to distil lation in the same apparatus in which the mix-‘ ing operation takes fractions. When an attempt was made to sep arate an equivalent reaction mixture without the place, or in separate appara- - tus. If such an operation is performed, it may involve concurrent flow of the amine mixture and basic solution to the zone of separation, or counter-current ?ow of the basic solution with respect to the amine-containing mixture with separation being accomplished immediately fol lowing the counter-current treatment. 'Thus, for example, the amine-containing mixture may This distillation was accom plished Without any di?iculty, and the respective amines were obtained as very sharply de?ned preliminary sodium hydroxide treatment, diffi culty was encountered both in connection with the purity of ‘the respective amine fractions, and because of plugging of the distillation equipment. 25 ' Example II ' A crude reaction mixture formed by the reac-' tion of acetaldehyde with ammonia and hydrogen be introduced into a fractionating column under by continuous vapor phase amination, was cooled pressure and temperature conditions ‘at which it to liquefy the ethyl amines and the higher boil is maintained in vapor phase, and the basic solu 30 ing products and also part of the ammonia. Hy tionmay be introduced into an upper part of the drogen, hydrocarbon and some ammonia were same column in liquid phase. Such an operation separated from the reaction mixture, and the re results 'in intimate contactv between the basic maining liquid products were passed into the cen solution and the amine-containing mixture, with 35 tral portion of a scrubbing column maintained at prompt reaction to form non-volatile salts, which a temperature of about 100° C. An aqueous so are dissolved in the aqueous phase, as discussed dium hydroxide solution of 10% concentration above, the aqueous phase passing downwardly was run into the column at a temperature of 125° _C., and a pressure of about -75 pounds per square through the column at the same time that the remaining amine-containing reaction mixture is removed overhead as a distillate. In case of practice of the invention on a re 40 inch, was maintained on the system during per formance of the ‘scrubbing operation by flow of _ the reaction mixture in ‘counter-current direc action mixture obtained by a continuous am tion to the ascending stream of gases to perform monation-reduction (amination) reaction, the the scrubbing operation. The liquid leaving the bottom of the scrubber‘consisted ‘essentially of water, sodium carbonate and. ‘sodium acetate, operation of treatment of the reaction mixture with a base is also preferably performed continu ously, and is preferably accomplished by intro while the volatile organic substances and‘ am duction of the amination reaction mixture con tinuously into the lower part of a column while introducing an aqueous basic solution into the upper part of this same column. monia passed overhead. Upon subsequent frac tionation of the overhead fraction, sharp separa In case of this 50 tions between the respective amines were ob tained. type of operation, the basic solution is prefer ably relatively dilute, caustic soda solutions of be ' tween 5 and 15% Part or all of the ?xed gases of the reaction Y ' ‘ Example III concentration being preferred, although a considerably wider range is permis~ sible. - By using relativelyv dilute basic solutions in practice of the process continuously, the di?i culty of precipitation of reaction products in the extraction column is avoided. , A crude reaction mixture resulting from pas sage of butyraldehyde together with a molecular 0 excess of hydrogen and ammonia over a catalyst consisting of pelleted nickel on kieselguhr at a temperature of approximately 155°C. was mixed with 10% of its weight of 50% NaOH solution and fractionally distilled with no appearance of interfering solid precipitated material in the col umn or condenser. Monobutyl amine of high mixture may be removed before the treatment with the base and subsequent distillation, and when the invention is practiced by accomplishing titre was obtained directly in this’fractionation. ‘the basic treatment in batch, this sequence is or Dibutyl amine and tributyl amine ‘were distilled dinarily used. In case of batch operation, much overhead as azeotropic mixtures with Water and more concentrated solutions may be-used than 65 separated from the water by decantation. The in case of continuous operation, and the inven water was returned continuously to the pot of tion may even by practiced by introducing the the distillation column. until all of the >di-' and base as a solid in the case of batch operation, since the reaction mixture will ordinarily con tri-butyl amines had been removed. The mix ture of di- and tri-butyl amines obtained in this tain suiiicient water to dissolve the added base, 70 way was dried by treatment with a‘ 50% 'NaOH ' solution. The amine layer containingthe dry Example I di- ‘and tri-butyl amines was then fractionated as pointed out above. toY-separate these amines from each other, and A crude reaction mixture obtained by passage respective amines were obtained in a'hlgh of acetaldehyde together with ammonia and hy— 75 these degree of purity. ‘ ‘ ' 2,41 1,802 6 5 ' 4 'sequently separating the amine bases from the resulting aqueous solution and distilling said amines to separate them from each other. 4. In the puri?cation of amine-containing re action mixtures resulting from reaction of ali phatic aldehydes containing from 2 to 6 carbon atoms with aminating agents and hydrogen, the process comprising mixing the crude reaction While the invention has been especially useful in treatment of reaction mixtures containing amines of from 2 to 6 carbon atoms in their alkyl also be prac radicals as discusscd'above, it can ticed in treatment of crude methyl amine reac tion mixtures obtained by ammonation-reduc tion of formaldehyde, and by treatment of reac tion mixtures containing amines of more than mixture containing the amine bases with an six carbon atoms in their alkyl radicals. 10 aqueous solution of an inorganic base and sub Various modi?cations are possiblewithin the sequently separating the amine bases from the scope of the invention, and I do not therefore resulting aqueous solution by distillation. wish to be limited except by the scope of the fol 5. In the puri?cation of ethyl amine-contain ing reaction mixtures resulting from reaction of lowing claims. a I claim: . 1. In the puri?cation of amine-containing re action mixtures resulting from reaction of ali phatic aldehydes with aminating agents and hy 15 acetaldehyde with aminating agents and hydro gen, the process comprising passing the crude reaction mixture upwardly in vapor phase through a distillation column in counter-cur drogen, the process comprising mixing the crude reaction mixture containing the amine bases with rent relationship to an aqueous solution of an from the resulting aqueous solution by distilla umn 'while the amine-containing mixture is passed upwardly in vapor phase through said col inorganic base passed downwardly through said an aqueous solution of an alkali metal hydroxide 20 column and removing the resulting aqueous solu and subsequently separating the amine bases tiondownwardly from a lower portion of the col ' 'tion. 2. In the puri?cation of amine-containing re action mixtures resulting from reaction of ali 25 umn. 6-. In the puri?cation of amineécontaining re phatic aldehydes with aminating agents and hy ' action mixtures resulting from reaction of a car drogen, the process comprising mixing the crude reaction mixture containing the amine bases with bonyl compound chosen from the class consist ing of aliphatic aldehydes and ketones, with an aqueous solution of an inorganic base and sub aminating agents and hydrogen, the process com sequently separating the amine bases from the 30 prising mixing the crude reaction mixture con resulting aqueous solution by distillation. taining the amine bases with an aqueous solu 3. In the puri?cation of amine-containing re tion of an inorganic base and subsequently sep 'action mixtures resultingy from reaction of ali arating the amine bases from the resulting aque aldehydes with aminating' agents and hy 35 ms solution by distillation. phatic drogen, the process comprising mixing the crude reaction mixture containing the amine bases with an aqueous solution of an inorganic base and sub JOHN F. OLIN.