INDUSTRIAL AND ENGINEERING CHEMISTRY
2928
(4) Davis, C. C., and Blake, J. T., “Chemistry and Technology of
(7) (8) (9) (10) (11) (12) (13)
Rubber,” New York, Reinhold Publishing Corp., 1937. Dow, W. H., IND.ENG.CHEM.,34, 1267 (1942). Faraday, M., Quart. J . Sci., 21, 19 (1826). Fisher, H. L., Am. SOC.Testing Materials Marburg Lecture, 1941. Howard. F. A., “Buna Rubber,” New York, D. Van Nostrand Co., 1947. Konrad, E., and Tschunkur, E., U. S. Patent 1,973,000 (1934). Manufacturing Chemists’ Assoc., “Chemical Facta and Figures,” 2nd ed., Washington, D. C., h‘lfg. Chemists’ Assoc., 1946. Mitchell, J. E., Jr., Trans. Am. I n s t . Chem. Engrs., 42, 293 (1946). Perkins, G. A , , and Davies, J. d.,U. S. Patent 2,271,092 (1942). Phillips Petroleum Co., Bull. 103 (1944).
Vol. 41, No. 12
(14) I b i d . , 265 (1948). (15) Phillips Petroleum Co., “Phillips and Synthetic Rubber,” 1943. (16) Poffenberger, N., et al., Trans. Am. Inst. C h m . Engrs., 42, 815 (1946). (17) Rubber Reserve Co., “Report on the Rubber Program 19401945,” Feb. 24, 1945. (18) I b i d . , Supplement No. 1 (April 8, 1946). (19) Schulze, W. A,, et al., Oil Gas J . , 46, 128 (March 1945). (20) Sebrell, L. B., IND.ENC.CHEM.,35,738 (1943). (21) Shearon, W. H., Jr., and McKensie, J. P., I b i d . , 40, 769 (1948). (22) Tschunkur, E., and Bock, W., U. S. Patent 1,938,730-1 (1933). (23) Whitby, G. s.,and Kata, bI.,IND. ENG.CHmf., 25, 1204, 1338
(1933). (24) Young, C . O., and Perkins, G. A., G. S.Patent 1,948,777(1934). RECEIVED June 15,
1949.
Organic Dehydration Reactions Using Activated Bauxite -
HEINZ HEINERIANNl, R. W. WERT, AND W. S. W. MCCARTER Porocel Corporation, Philadelphia, Pa. Activated bauxite is an abundant and relatively inexpensive catalyst for drying and for dehydration reactions in organic chemistry. Activated bauxite has been found to be equal or superior to the various forms of activated alumina now widely used for drying and to catalyze dehydration reactions. A number of well known dehydration reactions are described in which activated bauxite is substituted for activated alumina as a catalyst. The yield obtained in dehydration reactions is shown to be affected by such variables as reaction temperature, activation temperature, and iron content of the bauxite.
D
RYING and dehydration reactions in organic chemistry using inorganic desiccants as regenerable agents have been frequently described and are widely used. Among the most frequently mentioned desiccants are silica gel, thoria, tungsten oxide, and alumina. The alumina catalysts described in the literature are usually either alumina gels or forms of “activated alumina.” Relatively little work has been done with activated bauxite as a catalyst for this type of reaction. Yet bauxite, a naturally occurring hydrated alumina containing minor amounts of kaolinite, anatase, and ferric oxide, is interesting as an abundant and inexpensive catalytic agent. The bauxites used in the work described in this paper n‘ere of either -4rkansas or South American origin and had chemical and physical properties previously described (15, 19). Some typical chemical analyses are given below: % FetOs
% Si02
Ti02 1.30
Bauxite I 0.76 4.40 Bauxite I1 1.28 13.99 1.92 9.50 Bauxite I11 2.73 3.44 Bauxite I V 5.65 9.40 3.40 Bauxite V 18.60 6.40 2.60 a Column includes figures for NarO, KzO, etc.
% A1203 92.20
yo Undetermined“ 1.34
82.83 84.33 80.70
0 0
68.00
4.40
0.85
Iron content was varied by selection and blending of ores. The bauxites were thermally activated, either by large scale (18) or by laboratory procedures (16). Results of this work show that bauxite, in addition t o being an excellent drying agent (3, Q), is generally equivalent to other forms of alumina for con1
Present address, Houdry Process Corporation, iMarcus Hook, Pa.
densation reactions and that its iron content has in certain cases a promoting influence. APPARATUS AND PROCEDURE
Most of the dehydration reactions described in this paper were carried out by passing the reactants in either gaseous or liquid phase and a t atmospheric pressure through a bed of activated bauxite. The reaction chamber consisted of a Pyrex glass tube 3.75 em. in diameter and 105 cm. long. The catalyst bed of 100 t o 200 ml. was held in place by glass moo1 plugs and was preceded by a layer of glass beads t o serve as a preheating zone. The reactor ITas heated in an electric tube furnace of conventional design. Catalyst temperatures were measured by a thermocouple placed in a n axially located thermowell; furnace temperatures were controlled by means of a therniostatic regulator. Liquid reactants were charged from a calibrated buret to the reactor head by means of a n adjustable bellows pump, while gaseous reactants were admitted through a flowmeter. The reactor was connected to a water condenser, a receiver, and a dry ice stabilizer. Uncondensable gas was metered. The products obtained were, if possible, separated into aqueous and nonaqueous layers and idcn tificd by one or more of the following procedures: fractional distillation, the preparation of derivatives, refractive indexes, aaeotropic distillation, density, and acid number. INTRAMOLECULAR DEHYDRATIONS
Dehydration of Ethyl Alcohol. The dehydration of an aqueous solution of ethyl alcohol or of 95 to 99% alcohol can occur in three ways-viz., drying to absolute alcohol, dehydration to diethyl ether, or formation of ethylene. Under proper operating conditions bauxite will influence the reaction in such a manner that ’any one of these three compounds can be obtained as the main reaction product. DRYING.Derr (IO) has proposed a vapor phase process for drying ethyl alcohol to absolute alcohol in the presence of alumina adsorbent. Some ethylene may be produced as a by-product. The authors’ experiments show that very satisfactory vapor or liquid phase drying can also be obtained with activated bauxite as the adsorbent. In order to obtain absolute alcohol, long periods of intimate contact are necessary. A t atmosphcric temperature, liquid space velocities of less than 0.1 volume per volume per hour are required t o give absolute alcohol. Some dehydration of alcohol to ethylene always occurs. The amount of ethylene formed increases rapidly with increasing temperature, Thus, the heat of wetting, when alcohol first
December 1949
INDUSTRIAL A N D ENGJNEERING
CHEMISTRY
2929
PRODUCTION OF ETHYLENE. Bauxite and "activated alumina" show the same Absolute Alcohol Production. properties in regard to the conversion Liter of Adsorbent G. water of ethyl alcohol to ethylene. Since this Activation Operating Liquid adsorbed per ethylene Temp., Temp., Space Vel., 100 g. per liter of reaction has been described in the literac. c. Vol./Vol./Hr. adsorbent5 alcohol" Adsorbent ture (16, 23, 16),no further discussion is Bauxite 650 24 0.03 1.6 0.8 1.5 required. Bauxite 370 24 0.03 Pure alumina 660 80 0.3 0.4 4.6b Dehydration of Polyhydric Alcohols. Bauxite 370 80 0.3 2.6 3.96 0.3 2.0 10.1 GLYCOL. The dehydration of glycols in Bauxite 650 80 During period in which 100% alcohol was produced. the presence of activated bauxite prob Adsorbent prewetted a t l o o C. ceeds along the same lines as described for pure alumina (6, 17). Ethvlene glycol gives acetaldehyde and at about 300 ' C. and 1,Bpentanediol gives valeraldehyde. When contacts the adsorbent, causes increased ethylene formation. the hydroxyl groups are in the 1,2- or 1,3-position, oxides are This can be reduced by moistening the adsorbent a t a low temformed which, being unstable, isomerize to the aldehyde or even perature with alcohol, prior t o heating it to operating temperathe ketone. ture. By operating a t close t o atmospheric temperature (20" GLYCEROL.The conversion of glycerol to acrolein and water to 25" C.), ethylene production in the presence of bauxite is kept proceeds thermally at high temperatures. Yields, however, are to a minimum (0.501, of charge) (Table I ) . Higher yields of low and in t h e range of 4 t o 5% a t the required temperature of absolute alcohol and higher space velocities are possible by carry480' to 540" C. Much better yields are reported by distilling ing out the operation in the vapor phase a t 80" C. (Table I ) . glycerol in the presence of fuller's earth or siliceous clays (18) A t this temperature, a bauxite activated a t 370" C. is superior or heating it batchwise in the presence of alumina and kieselguhr to one activated at 650" C., while bauxites activated in the range (26). 370" to 650" C. are equivalent for operation a t atmospheric In the presence of activated bauxite the reaction proceeds with temperature. fair yields a t temperatures lower than those required for the Yields of 50 and 85 ml. of anhydrous alcohol per 100 grams of thermal reaction. Reaction times are fairly short (Table I V ) bauxite were obtained when charging 96 and 98oJ, alcohol, reand permit the reaction to be carried out continuously by passing spectively, a t a space velocity of 0.03 volume per volume per hour a stream of glvcerol through a bauxite bed heated to reaction temto a percolation column a t a temperature of 24" C. The total perature. drying capacity of bauxite is given in Table 11. While the reaction itself is endothermic, a great deal of heat is developed when the glycerol first wets the catalyst. TemperaTABLE11. TOTAL DRYINGCAPACITY OF BAUXITE, ACTIVATEI) ture control is made difficult, due to the initial rise in temperature AT 650" C., FOR ETHYL ALCOHOL which averages 150" C. and the rapid heat consumption which (Liquid space vel., 0.03 vol./vol./hr.; operating temp., 26' C.: charge follows. It was found necessary t o maintain the temperature alcohol, 95.2%) above 400" C. in order to get yields of more than 10% acrolein. G. Water Removed per Concentration M1. of Effluent 100 G. Adsorbent Alcohol per 100 G . of Effluent Bauxite activated a t 590" to 650" C. gave higher yields than Alcohol, % Adsorbent From fraction Total bauxite activated a t 430" C. (Table IV). Considerably more 1.56 1.56 100 41.7 0.36 1.92 99.9-99.0 10.0 cracking and catalyst carbonization, as evidenced by the lower 0.11 2.03 98.9-98.0 4.0 liquid recovery, occurred with the bauxite activated a t the lower 0.45 2.48 97.9-97.0 24.0 0.25 2.73 96.9-96.0 23.8 temperature. Some acrolein polymerization was observed. 0.02 2.75 95.9-95.2 6.2 OF ABSOLUTE ALCOHOL FROM 94% ALCOHOL TABLE I. PRODUCTION
water
-a
il
pr
+.
.
By using multiple stage percolation and contacting aqueous alcohol first with partially spent, then with increasingly fresh adsorbent, the yield of absolute alcohol can be nearly doubled. Spent bauxite can be restored to full activity by purging with steam and thermally reactivating. PRODUCTION OF DIETHYL ETHER.Good yields of ether were obtained b y passing ethyl alcohol over bauxite a t temperatures of 270" t o 290" C. These temperatures are close to the range (240" to 260" C.) in which pure alumina has been found to be most effective ( 4 , 24, 26, 28). The optimum reaction temperature with bauxite is 270" C. (Table 111) at a liquid space velocity of about 0.6 volume per volume per hour. Low iron bauxite was found superior to high iron bauxite. The bauxite should be activated a t about 600" C. prior to use. About 10% of the charge alcohol is converted to ethylene.
TABLE 111. DIETHYLETHERFROM ETHYL ALCOHOL Reaction Liquid 76 Alcohol Recovered as % ' Temp., Space Vel.. EthylCatalyst Fez08 C. Vol./Vol./Hr. Ether enen .4lcohol 0.6 21.4 7.6 71.0 Bauxite 1.26 255 270 0.6 6 4 . 4 9.9 25.7 Bauxite 1.26 59.9 290 0.5 17.6 22.5 Bauxite 1.26 53.7 22.2 24.1 0.6 5.65 270 Bauxite 49.3 5.65 290 0.5 24.8 25.9 Bauxite a Ethylene determined by difference between sum of ether and alcohol recovered a n d charge alcohol.
TABLE IV. Activation Tp$, Catalyst
PRODUCTION OF ACROLEIN Glyoerol Average Converted Liquid Reaction Llquld to Space Vel. T:m$., Recovery, Acrolein, VOI./VOI /dr 9% 9%
Dehydration of Ketones. Dohse (11) has described the batch conversion of acetone to mesitylene which proceeds a t 260 O to 450" C., under pressures of 1 to 300 atmospheres, in the presence of bauxite which has been activated a t above 540' C. The authors have found that in continuous operation at atmospheric pressure and temperatures in Dohse's range, yields of up t o 43y0 can be obtained a t space velocities of the order of 0.5 volume per volume per hour. A t liquid acetone temperatures, some diacetone alcohol is formed. INTERMOLECULAR DEHYDRATIONS
Alcohols and Ammonia. The formation of primary, secondary, and tertiary amines from alcohols and ammonia can be catalyzed by various metal oxides (6, 8, 9,12, 26, $7, SO). Thoria has been described as a very active catalyst, pure alumina as slightly less active. Yields described in the literature can be considerablv increased by using activated bauxite as the catalyst. Because
INDUSTRIAL AND E N G I N E E R I N G C H E M I S T R Y
2930
Vol. 41, No. 12
the yield of secondary amine declining more rapidly than that of primary amine. More olefu, is produced with fresh thall Iyit11 partially spent catalyst. Liquid space vel, 7 ~ ~ 9t'0Butyl ~ Alcohol l Converted Alcohol and Primary Amine. The reactions between primary Reaction of Alcohol, Alcohol to Recovered Amines Ether aromatic amines, such &s aniline, and alcohols, to form sucondary Temp,, C , Vol.,Voi,,Hr, 88.0 12.0 0 0 and tertiary amines, such as ethyl- and diethylaniline in the pres230 0.30 260 0.30 76.2 18.2 0 5.6 ence of dehydrating materials such as alumina, thoria, silica gel, 300 0.36 58.8 35.4 0 5.8 g. 1 13.2 and zirconia, have repeatedly been investigated ( 7 , 12, 20, 21, 320 0.31 19.2 58.8 345 0.32 28.4 29.7 10.3 31.6 26, 59). These investigatxs estab320 0.60 80.4 17.6 1.5 0.5 lished an optimum temperature range of 200" to 400' C. and found that mixed TABLEVI. AMINESFROM BUTYLALCOHOL 4 N D A M M O N I A OVER ACTIVATED BAUXITE as, for example, those (Reaction temp., 320O C.; liquid space velocity of alcohol, 0.3 vol./vol./hr.; molar ratio, pared by coprecipitation of alumina NHs: CIHBOH = 1.6: 1) Catalyst and iron oxide, are inferior to unpro70 Butyl Alcohol Converted to Activation 70 Butyl inoted oxides (29). % temp., Alcohol Total Prim. See. Tert. Type FezOa C. Recovered Olefin E t h e r amine amine amine amine When aniline and ethyl alcohol are Bauxite 2.73 320 48.5 19.1 0 33.4 24.0 9.4 0 passed over bauxite catalysts in the 2.73 Bauxite 370 42.3 7.4 8.1 42.2 24.8 11.7 5.7 Bauxite 2.73 425 19.2 28.8 9.1 previously described manner, the reac13.2 9.1 58.5 20.6 Bauxite 2.73 480 27.8 11.9 8,5 51.8 26.1 14.4 1 1.3 t'ion was found to proceed a t lower Bauxite 2.73 595 29.0 15.3 13.4 42.3 26.1 5.4 10.8 2.73 705 34.9 11.6 Bauxite 12.0 41.5 24.0 7.1 10.4 temperatures and with higher yields Alumina 0 425 35.7 26.5 2.8 36.0 31.6 2.8 1.6 than can be obtained with pure alumina. Bauxite 0.76 425 27.8 11.9 8.5 t1.S 2 6 . 1 14.4 11.3 28.8 9.1 a t the same temperature (Table VII). Bauxite 2.73 425 19.2 13.2 9.1 a8.5 20.6 Bauxite 4.0 425 27.6 12.3 9.5 50.6 19.3 25.1 6.2 The ferric oxide in the bauxite appears to Bauxite 5.65 425 27.2 15.0 8.7 49.1 16.3 25.3 7.5 promote the reaction, and conversion yields increase with the ferric oxide content up t o about 6% ferric oxido. of the ease of separation of products, the reaction between butyl Best yields were obtained a t 275" C., at, a space velocity of 0.3 alcohol and ammonia was studied as typical for this type of and an alcohol to aniline molar ratio of 1.45 to 1. Increase of the molar ratio leads to an increase in the proportion of condensation. Operating conditions found as most suitable for maximum protertiary amine (Table VII). A bauxite activation temperature duction of amines were an alcohol space velocity of 0.3 to 0.4, of 600" C. was superior to one of 425" C. an ammonia to alcohol ratio of between 1.5 to 1 and 3 to 1 deAlcohols and Aldehydes. A41coholsand aldehydes react in the presence of dehydrating agents such as calcium chloride to form pending on the type of amine desired, and a react'ion temperature acetals ( 1 , Z ) . The reaction is carried out in batch operation and of 320" C. (Table V). Primary amines predominated a t a high, secondary and tertiary amines at a low ammonia to alcohol ratio. the catalyst must be destroyed in the process of srparating it Yields a t the optimum reaction temperature are dependent on from the reaction products. Activated bauxite was found to catalyze this reaction a t room the space velocity. Doubling the space velocity will reduce amine production by 70% but will also reduce by-product oletemperature. Sufficiently intimate contact is obtained by percolating the liquid reactants a t a very low space velocity through fin production by as much as 98%. While low yields of amines a bed of bauxite. The catalyst can be regenerated by convenare obtained in the reaction temperature range 230' to 300 ' C., tional means after it becomes spent. olefin production is also small. The dehydration of alcohol to olefin increases with the reaction temperature and becomes the Best yields were obtained a t close to room temperature and a1 primary reaction at temperatures not much higher than the space velocities of the order of 0.03 volume per volume per hour mith alcohol to aldehyde molar ratios of about 1 to 1 to 2 to 1 optimum (320" '2.). The activation temperature of the bauxite is of importance for (Table VIII). Catalyst activity declines as the amount of water of reaction retained on the bauxite increases. It can be prothe yields of products obtained (Table VI). Largest total amine longed by using anhydrous alcohol as reactant. A small amount production is obtained with bauxite activated a t 425" C. While (usually not more than 5 % ) of higher boiling by-products, probprimary amine production is largely independent of the activation temperature, that of secondary and tertiary amine seems ably aldehyde polymers, are formed. to be influenced thereby. Catalytic activity appears to be Alcohol and Acid. The esterification of alcohols and organic acids, which normally proceeds as a thermal reaction, can be carrelated to the iron content of t,he bauxite, optimum conversion ried out in the presenceof activated bauxite, resulting in considerbeing obtained with a bauxite containing about 3% ferric oxide ably higher yields of esters particularly in the case of higher ali(Table VI). Catalyst activity declines very slowly with use, p h a t i c a l c o h o l s a n d a l i p h a t i c or aromatic acids. The reaction conditions required for maximum yields indicate that, the bauxite serves mainly as TABLE VII. CONVERSION OF ANLLXE TO ETHYLAND DIETHYLANILINE an agent to remove and retain water of Reaction Conditions Catalyst Conversion, % Aniline Liquid reaction, thus preventing thc reversc t o Product Activation 8paoe reaction. The reaction proceeds best, % ' temp., Temp., vel., Alcohol: Ethyl- DicthylType Fez08 C. C. vol./vol./hr. aniline aniline aniline Total ti,- refluxing- a mixture of alcohols and .4lutnina 0 600 275 0.31 1.45 23.3 0 23.3 acids using a conderiaer packed with Bauxite 1.26 600 275 0.31 1.45 30.1 1.1 32.3 Bauxite 5.65 600 275 0.28 1.45 83.9 3.3 87.2 act,ivated bauxite as described by Bauxite 18.6 600 275 0.30 1.15 70.0 4.6 74.6 Gordon et al. ( 1 4 ) . In the present exBauxite 5.65 425 275 0.28 1.46 57.7 59.0 periments, an excess of alcohol was Bauxite 5.65 600 275 0.28 1.45 83.9 31 .. 33 8 7.2 Bauxite 5.65 600 275 0.30 2.10 59.9 15.2 75.1 emoloved. the mixture was refluxed for Bauxite 5.65 600 250 0.32 1.45 51.9 1.5 53.4 various periods of time, and the per Bauxite 5.65 600 275 0.28 1.45 83.9 3.3 87.2 Bauxite 5.65 600 305 0.34 1.45 69.3 6.7 76.0 cent esterification was determined from the acid number. High activation
TABLE v.
BUTYLALCOHOL .4XD BAUXITEACTIVATED AT 425 ' C.
k v I I N E S FROM
hd.IMONIA OVER
~
~
O
I
.
i
INDUSTRIAL AND ENGINEERING CHEMISTRY
December 1949
TABLE VIII. ACETALFORMATION FROM ETHYL ALCOHOL AND ALDEHYDE OVER BAUXITE,-4CTIVATED A T 650" c. Reaction Liquid Molar Ratio, Tzmp., Space Vel., Aldehyde .4lcohol: Aldehyde C. Vol./Vol./Rr. Propionaldehyde 2: 1 50 0.07 Propionaldehyde 2: 1 25 0.07 Propionaldehyde 2: 1 25 0.07 0.03 Propionaldehyde 2: 1 25 Propionaldehyde 2: 1 25 0.02 Propionaldehyde 1:l 25 0.03 Propionaldehyde 2: 1 25 0.03 Butyraldehyde 2: 1 25 0.03
b
Acetal Yield, % of Theory 0 18 18 50 52 50
50
42
TABLEIX. ESTERIFICATION OF ALCOHOLS AND ACIDSIN PRESENCE OF ACTIVATED BAUXITE
Alcohol Ethyl Ethyl Butyl Capryl Capryl Capryl Capryl Capryl
Acid Acetic Acetic Acetic P hthaljc Phthalic Acetic Acetic Acetic
Bauxite Activation Temp., 0
c.
THE
% Esterificationa Reflux Time,
Hr.
425 600 600 600 980 425 600 600
Thermal reaction only
Bauxite catalyzed
20 20 46 62 62 42 42 55
20 27 57 69 76 82 84 92
2931
TABLEXI. ACETONITRILEFROM ACETICACID AND AMMONIA OVER
Catalyst
BAUXITE
Reaction Conditions Space vel., Temp., vol./vol./hr. of acid
Type
yo
Fez08
Activation temp., C.
Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Bauxite Alumina Bauxite Bauxite Bauxite
0.76 0.76 0.76
595 595 595
0.76 0.76 0.76
595 595 595
2.73 2.73 2.73 2.73 2.73
425 480 540 595
650
425 425 425
0
425 425 425 425
425 425
0.76 2.73 5.70
c.
0.60
53 82 48 42 48 40 95 87 95 81 84
0.60 0.60 0.60 0.60
a2 87 95 77
370 425
0.59 0.59 0.51
500
500
0.19 0.51
500
0.80
425
0.60
500
425
Yield,, yo Acid Converted t o Nitrile
0.60 0.60
0.60
deterioration is very slow. The catalyst can be regenerated by conventional means. Two layers, a n aqueous and an oily phase, are condensed from the reactor effluent, and nitrile and acid are separated from the oily layer by fractional distillation.
Based on acid charged.
ACKNOWLEDGMENT
TABLEX.
ESTERIFICATION OF CAPRYL ALCOHOL AND ACETIC ACID
The authors wish t o acknowledge the contribution of W. A. Hodes to the early phases of this work.
% Esterification after
w
w
Catalyst
2 Hr.
5 Hr.
None Activated bauxite Sulfuric acid Bauxite and sulfuric acid
42 70 81 98
55
81 81 98
temperatures of the bauxite and fairly long reflux times are desirable (Table IX). This method is especially useful for esterifications in which water is the lowest boiling component of the system. Yields obtained with bauxite approximate those obtained with 1% of sulfuric acid as esterification catalyst. When the procedure described for the use of a bauxite catalyst was employed and, in addition, sulfuric acid was added to the reaction mixture, better yields of ester were obtained than with either catalyst alone. The results shown in Table X were obtained by refluxing 65 grams of acetic acid and an equimolecular quantity of capryl alcohol ( a ) in the absence of catalyst, (b) with 55 grams of activated bauxite in the reflux condenser, (c) with 1% of sulfuric acid in the reaction mixture, and ( d ) with both bauxite and sulfuric acid as described. Acid and Ammonia. The catalytic dehydration of the nascent amide, formed from acetic acid and ammonia, t o the nitrile has been studied in the presence of silica gel, thoria, and alumina catalysts (26, $1). While nitrile yields of up to 85% have been described for the reaction when carried out in the presence of pure alumina at 500" C., the present experiments show that higher yields (up t o 95%) can be obtained a t a lower reaction temperature by substituting bauxite of proper activation and ferric oxide content. The components charged to the catalyst must be mixed a t a high temperature in order t o avoid the formation of ammonium acetate. The acid is charged a t a liquid space velocity of about 0.6 volume per volume per hour to a bed of bauxite with a small molecular excess of ammonia. An increase in the ammonia t o acid ratio decreases the nitrile yield. The reaction proceeds best a t a temperature of 425' C. in the presence of bauxite, containing about 3yo ferric oxide, which has been activated in the range 425' to 540" C. (Table XI). Similar yields of nitriles were obtained when propionic acid was substituted for acetic acid. The process is continuous and catalyst
LITERATURE CITED
Adams, E. W., and Adkins, H., J . Am. Chem. SOC., 47, 1358 (1925). Adkins, H., and Niessen, B. H., Ibid., 44, 2749 (1922). Aepli, 0. T., and McCarter, W. S. W., IND. ENG.CHEM.,ANAL. ED.,17,316 (1945). Alvarado, A. M., J . Am. Chem. Soc., 50, 790 (1928). Beati, A., and Mattei, G., Ann. chim. applicata, 30, 21 (1940). Briner, E., and Gandillon, J., Helv. Chim. Acta, 14, 1283 (1931). Brown, A. B., and Reid, E. E., J . Am. Chem. SOC.,46, 1836 (1924). Brown, A. B., and Reid, E. E., J . Phya. Chem., 28, 1067 (1924). De Carli, F., and Galimborti, L., Boll. sci. facoltb chim. ind. univ. Bologna, 1940, 62. Derr, R. B. (to Aluminum Co. of America), U. 8. Patent 2,137,605 (Nov. 22, 1939). Dohse, H., and Schuster, C., Ibid., 1,977,178 (Feb. 21, 1933). Dorrell, G. W., J . Chem. Soc., 127, 2399 (1925). Freund, E., U. S. Patent 1,672,378 (June 5, 1924). Gordon, P. L., and Aronowitz, R., IND.ENG.CHEM.,37, 780 (1945). Heinemann, H., Krieger, K. A4., and McCarter, W. S. W., Ibid., 38,839 (1946). Ipatieff, V. N., J . prakt. Chem., 67, 421 (1923). Ipatieff, V. N., and Leontovich, J . Rziss. Phys. Chem. SOC.,35, 606 (1903). King, H. L., Laughlin, C. D., and Gwyn, H. M., Oil Gas J.,42 No. 49,236 (1944). LaLande, W, A,, Jr., McCarter, W. S.W., and Sanborn, J. R.. IND. ENG.CHEM.,36, 99 (1944). Mailhe, A,, French Patent 23,891 (Aug. 4, 1856). Mailhe, A., and De Godon, F., Compt. rend., 166, 467 (1918). Mitchell, J. A., and Reid, E. E., J . Am. Chem. Soc., 53, 321 (1931). Nitkin, V. M., and Razvmov, N. V., J . Gen. Chem. (U.S.S.R.), 11, 133 (1941). Pease, R. N., and Yung, C. C., J. Am. Chem. SOC.,46, 390 (1924). Sabatier, P., and Gaudion, G., Compt. rend., 166, 1033 (1918). Sabatier, P., and Mailhe, A., Ibid., 147, 106 (1908); 148, 227, 898 (1909) ; 150,823 (1910). Sabatier, P., and Reid, E. E., "Catalysis in Organic Chemistry," New York, D. Van Nostrand Co., 1922. Senderens, J. B., Compt. rend., 148, 227 (1909), Shuykin, N. I., Balantin, A. A., and Dinov, J . Phys. Chem., 39, 1207 (1935). Smolenski, E., and Smolenski, K., Roczniki Chem., 1, 232 (1921). Van Epps, G. D., and Reid, E. E., J . Am. Chem. Soc., 38, 2128 (1916). RECEIVED March 25,1949.
