Showing papers in "Industrial & Engineering Chemistry Chemical & Engineering Data Series in 1958"

Solubility of Benzene in Water.

Abstract: F o r the determination of individual mass transfer coeff ic ients for the benzene-water system, the mutual solubility of the components is required. T h i s paper dea ls with the solubility of benzene in water. T h e interpretation by Seidell (23) of the then-available portion of the present (1, 3-5, 7-19, 21-23, 25, 26) data on the solubility of benzene in water indicated a relationship that continually increased with temperature in a manner similar t o h i s other interpretations on the solubility of hydrocarbons in water. T h e more recent data of Bohon and Claussen (4) were the first to indicate a minimurn in the solubility curve for benzene (and other aromatic compounds), although Hill (13) suspected one. Taken a s a whole, the avai lable data might have been considered discordant. As a precise analytical technique for the analysis of benzene in water was needed for mass transfer s tudies , it was decided t o demonstrate and prove the technique by a redetermination of the solubility relationship. Ultraviolet spectrophotometry was selected a s the analytical tool. Study and experience indicated that the analytical technique had to b e developed with great care to avoid errors due to excess ive volatility, such as found by Saylor, Stuckey, and Gross (22), to improper calibration, to temperature-induced hazes , and perhaps to wall adsorption effects.

Vapor-Liquid Equilibria for Binary Systems of Methanol, Ethyl Alcohol, 1-Propanol, and 2-Propanol with Ethyl Acetate and 1-Propanol-Water.

Abstract: T h e design and economic operation of fractionating equipment require knowledge of vapor-liquid equilibrium relations of the systems involved in the separation process. Equilibrium data a t two or more temperatures for binary systems composed of a common component and several in a series of homologous compounds allow calculation of thermodynamic properties and interpretation of behavior of the mixtures in relation to the chain length or structure of the homologs. Few experimental investigations of such a series of systems have been reported. Scatchard and his coworkers (25-29) calculated the thermodynamic properties of binary mixtures and, in some instances, t he extent of association and hydrogen bond strength from vapor-liquid equilibrium measurements. Mertes and Colburn (19) reported resul ts of isothermal vapor-liquid equilibrium measurements on some of the industrially important systems of hydrocarbons with furfural and made u s e of the variation of activity coefficients with temperature to calculate the heats of solution of the hydrocarbons in furfural. Thus, isothermal vapor-liquid equilibrium data can be utilized to calculate the.heats of mixing for those systems for which experimental data cannot b e taken conveniently in a laboratory. Binary systems of methanol, ethyl alcohol, 1-propanol, a d 2-propanol with ethyl acetate and 1-propanol with water were studied in t h i s investigation. Selection of t hese particular systems was based upon the availability of information on solution behavior from other s tudies (I).

Properties of Binary Mixtures as a Function of Composition.

Abstract: D a t a on physical properties of mixtures as a function of composition and temperature are valuable in correlating other properties and in analytical studies. In this and subsequent investigations an attempt w a s made to develop experimental data for a number of systems on which generalized correlations could be developed relating Composition and the property evaluated based on the properties of the pure components, Thus, eight binary systems having a rather wide range of properties (particularly interfacial tension) and in most cases, representing nonideal liquid mixtures were studied. The systems were: 1-propanol-water; toluene-n-octane; water-1-butanol; acetone-1-butanol; benzene-2-chloroethanol; carbon tetrachloride-1-propanol; ethyl alcohol-1,4-dioxane; and methanol-l,4-dioxane. The properties determined were: refractive index vs. composition, liquid density vs. composition and temperature, interfacial tension a t the boiling point and a t 3OoC. as a function of composition, liquid viscosity as a function of temperature and composition, and vapor viscosity a s a function of temperature and composition. Because of the peculiar variation of interfacial tension and viscosity with composition a t the boiling point, no general correlations have been developed. More data on both binary and ternary systems are necessary.

Permeability of Amylose Film to Moisture Vapor, Selected Organic Vapors, and the Common Gases.

Abstract: A mylose, the linear starch fraction, has been reported as a raw material useful for preparation of self-supporting f i l m s (4, 14, 22). Exploitation of such a use is, of course, dependent on the economical production of amylose. Most common starches contain approximately 1/4 amylose and 3/4 amylopectin, the branched fraction (10). In the past few years the breeding of a hybrid corn containing 50 to 80% amylose (5, 13, 23) in the starch has renewed interest in the potentialities of amylose a s a raw material for such industrial u ses a s f i l m s and fibers. A large proportion of al l types of commercially produced f i l m s now are used for packaging, such as wrapping, liners, and bags. The value of amylose f i l m s in such applications is dependent, in part, on their permeability characterist ics, for which data have been obtained in the present studies. The most important permeability factors in packaging foods and drugs are water vapor and gas permeabilities. Successful packaging of any food product must take one or both of these factors into account-for example, respiration of fresh fruits and vegetables necessi ta tes some permeability t o carbon dioxide (15). Food products containing fat , such a s roasted ground coffee and dried whole milk, are susceptible to spoilage by oxygen (19). In some ins t ances another permeability characterist ic assumes importance and must be taken into consideration in packaging foodstuffs. Permeability of f i l m s t o organic vapors falls in this category, Th i s factor is of interest because of i t s relation to possible lo s ses or retention of flavor and odor consti tuents of packaged materials. Studies carried out in work on amylose f i l m s include determinations of water vapor transmission a t various relative humidity gradients; measurements of permeability t o vapors of selected organic acids, alcohols, ketones, aldehydes, and esters ; and determination of permeability to nitrogen, oxygen, air, carbon dioxide, ammonia, and sulfur dioxide.