The Ternary System: Isopropyl Alcohol, Toluene and Water at 25°

Abstract

579Continuing a series of previously described in-vestigations2 of similar systems, solubility and distribution studies have been carried out with the system isopropyl alcohol, toluene and water a t 25.0'.Materials.-Carefully purified water was used. I t was prepared by the partial condensation of steam from an alkaline permanganate solution.The toluene was the better of the two grades obtainable from the Eastman Kodak Company. As efforts to purify this material further failed to alter its physical constants it was used as received. The specific gravity dZ54 was 1.4938.The isopropyl alcohol, from Eastman Kodak Company, was refluxed for many hours with fresh lime. It was then distilled into a carefully dried all glass still from which it was fractionally distilled. The middle portion of the distillate, boiling from 81.7 to 81.9' was used. It had a specific gravity dZ64 of 0.78087 and a refractive index n25D of 1.3748.Procedure and Results.-The details of the experimental work which seem to different workers to be most suitable for different ternary systems differ so that it is hardly possible to state that one system was studied by a previously described procedure and give an entirely truthful impression. The procedure followed in this investigation was like that described previously3 with the following modifications. The titrations were carried out a t 25.0' in small Erlenmeyer flasks which were shaken mechanically in the constant temperature bath except when additions of water or toluene were made from weight pipets. The values obtained with toluene as a titrant agreed with those obtained with water as the added liquid as closely as the water titrations agreed with each other. Preliminary titrations were carried out with materials not of the highest purity so that in the final titrations dropwise addition of all but the last few tenths of a gram of titrant was avoided.The appearance of the end-point varied with(1) Present address: Eastman Kodak Company, Rochester, NewSee (1939).different proportions of alcohol and toluene in the liquid titrated. At the lower end of the water rich part of the binodal curve relatively large droplets of the second phase appeared a t the endpoint; both phases appeared perfectly clear even after separation. As points further up on the curve were determined the droplets of the toluene rich phase separating out a t the end-point became smaller and smaller until a t an alcohol concentration of about 35% the mixture had the appearance of a fine mist. Above about 43% alcohol across the top of the curve and down to about 42% alcohol on the toluene rich side a still finer state of subdivision, a "milkiness," appeared a t the endpoint. In this region the first indication that the end-point was being approached was an opalescence, probably like that noted on cooling certain two component systems just before they separate into two liquid phases a t the critical temperature. The remainder of the toluene rich side presented end-points similar to those on the lower part of the water rich side. Th...

Effect of 2-Propanol on the Transfer Hydrogenation of Aldehydes by Aqueous Sodium Formate using a Rhodium(I)-sulfonated Triphenylphosphine Catalyst

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