1230
INDUSTRIAL AND ENGINEERING CHEMISTRY
water bath and decanting the lower lafer of the distillate until the evolution of lower layer had practically ceased. The reaction mixture was then filtered and distilled. The fraction boiling a t 183-188 O C. was further purified by dissolving in ether and washing with sodium bicarbonate solution. Sfter removal of the solvent and drying, 70 grams of glycol diacetate were obtained (saponification equivalent: theory, 73 grams per equivalent; found, 75 grams per equivalent). The yield was 480j0. Ethyl chloroacetate was prepared in a similar manner by refluxing 69 grams (1.5 moles) of ethyl alcohol, 94.5 grams (1 mole) of chloroacetic acid, 100 ml. of benzene, and 33.7 grams of ZeoKarb H (25.9% water) and decanting the lower layer of the azeotrope as formed. After 7 hours the benzene and excess alcohol were removed by distillation, and the catalyst was removed by filtration. The undistilled residue ivas clear and had only a light yellow color. This residue had an acid number of 35.9 and an ester number of 352; this corresponded to an 87.5y0 yield of ethyl chloroacetate. ESTER ALCOHOLYSIS
Methyl acetate was prepared by gently refluxing 65 grams (0.5 mole) of amyl acetate, 64 grams (2 moles) of methanol, and 5 grams of Zeo-Karb H (air-dried) under an 8-inch packed column and taking off the methanol-methyl acetate azeotrope (boiling point, 54" C.) as formed. The reaction rate was relatively slo~v, but after 27 hours a yield of 74.5% methyl acetate was obtained. The residue in the reaction flask was identified as being mostly amyl alcohol. The slow reaction rate apparently reaulted from low catalyst dosage in terms of the available acidity. 9 parallel experiment, tn which the catalyst was an amount of sulfuric acid equivalent to the hydrogen exchange capacity of that Zeo-Karb H used in the initial ester alcoholysis experiment, gave almost exactly the same rate of reaction. ESTER HYDROLYSIS
Attempts to hydrolyze esters, including fats, using Zeo-Karb H a catalyst were less successful than the other reactions reported here. I t is believed that the difficulty resulted from the poor contact attainable in the three-phase system ester-watercation exchanger. The one experiment in which a mutual solvent was employed was partially successful. In this case 20 grams of n-butyl oleate, 100 ml. of water, 150 ml. of ethanol, and 100 grams of Zeo-Karb H were refluxed for 7 hours. The catalyst was removed by filtration and the reaction mixture distilled to remove the solvent and water. Analysis of the residue indicated a 9% yield of oleic acid. 6s
ACETAL FORMATION
Mixed glycerol formals were formed by heating 46 grams (0.5 mole) of glycerol, 15 grams (0.5 mole) of p-formaldehyde, and 6 grams of Zeo-Karb H (air-dried) in a 120-130" C. bath and taking off water as formed. Water evolution ceased after 4 hours. The &-aw-colored liquid in the reaction flask was cooled and filtered to remove the catalyst. Upon distillation 90% of the product boiled a t 190-194" C. Van Loon ( 4 ) reported 193-194" C. as the boiling point of mixed 01,a'-and a ,&glycerol formals. Di(n-butoxy)-methane was prepared by heating 74 grams (1 mole) of n-butanol, 15 grams (0.5 mole) of p-formaldehyde, and 9 grams of Zeo-Karb H (air-dried) and taking off water as formed. The product was then distilled and the cut boiling a t 177-179 C. was separated. Upon redistillation more than 90% of this cut distilled a t 179" (3.;' this corresponded t o the recorded boiling point of di(n-butoxy)-methane. This fraction weighed 76.7 grams (96% yield of the acetal). In this experiment the product was distilled directly from the reaction flaqk without separating the Zeo-Karb catalyst. There was no charring or discoloration apparent in the flask or in the product.
Vol. 38, No. 12
ACETAL ALCOHOLYSIS
Methylal was formed from 56 grams (0.35 mole) of di(7~butoxy)methane by refluxing under a column with 45 grams (1.4 mole) of methanol and 10 grams of Zeo-Karb H (air-dried) and taking off the methanol-methylal azeotrope (b.p., 42" C.) ap formed. The reaction rate was rather slow, and, when the experiment ivas shut down after 16 hours of refluxing, a total of 20 grame of the methanol-methylal azeotrope iyas obtained. On the basis of the published composition of this azeotrope (92% methylal), the yield was 69%. DEHYDRATION O F ALCOHOLS
Isobutylene mas readily produced by heating 7.4 grams (0.1 mole) of t-butanol in 50 ml. of xylene with 0.54 gram of Zeo-Karb H (air-dried). The flask was connected through a reflux condenser with a calibrated receiver inverted in a water bath. When the flask was gently Tvarmed, regular gas evolution developed without boiling. In three hours 1250 ml. of gas identified as isobutylene were evolved; this corresponded to 52% of theory. Some evidence of Zeo-Karb H-catalyzed castor oil dehydration was obtained, although the reaction temperature was so high that decomposition of the catalyst was evident. Seventy-five grams of castor oil and 28.2 grams Zeo-Karb H (47% water) were heated in a 180-200" C. bath for 3 hours, cooled, and filtered During the heating period there was some evalution of sulfur dioxide, probably as a result of partial decomposition of the cation exchanger a t this high temperature. Analysis of the product by the Wijs method indicated that the iodine number of the castor oil had been increased from 66 t o 80. SUCROSE INVERSION
Sucrose inversion was tested qualitatively a t 25 O , 50 ', and 90 'C by treating 45-ml. samples of 33% sucrose solution with 1 gram each of air-dried Zeo-Karb H, and testing with Fehling solution a t intervals. The results of this experiment are given in the following table, in which a minus sign indicates a negative test and plus signs indicate positive tests ranging from a trace reaction tm a very strongly positive reaction. 0 min.
Blank (no catalyst)
c. 900 c. 250 50' C.
--
Sucrose Inversion at Reaction Time of: 2 min. 4 min. 8 min. 10 min. 30 min.
-
-
+
-
-
-
+ ++t ++ + ++ ++ +++ ++++
LITERATURE CITED Cheetham, U. S. Patent 2,334,904 (Nov. 23, 1943). Dierichs, Report P B 866, Office of Technical Services, Dept. of Commerce, Washington, 1945. Dutt, J . Chem. SOC.,123,2714 (1923). Loon, van, Rec. trau. chem., 48, 173-90 (1929). Myers, Eastes, and Myers. IND. ENQ.CHEM., 33, 697-706 (1941) Spurlin, U. S. Patent 2,364,925 (Dec. 12, 1944). Thompson and Leuck. J . Am. Chem. SOC.,44, 2894 (1922). Tiger, J . Am. Water W o r k s Assoc., 26, 357-67 (1934). Tiger, Trans. Am. SOC.Mech. Engrs.. 60, 315-25 (1938). Van Schaack, U. S.Patent 1,697,295(Jan. 1, 1929). Zimmerli, U. S. Patent 1,708,404 (Apr. 9, 1929).
Correlating Equilibrium Constants-Correction Attention has been called to the folloq-ing mistakes in drafting of Figures 2 and 4 of this article by D. F. Othmer and A. H. Luley in the April, 1946, issue. In Figure 2, page 408, the temperature Tines should eachobe labeled 100" C. higher, and will then read 700°, 800", 900 , llOO", 1300" C. In Figure 4 the 450" C. line should be approximately inch to the right of its present location. This relocation also moves to the right the uppermost points on curves (1) and (2) so that they fall closer t o their respective lines.
