bluuebunny/crossref_metadata_2025_split huggingface dataset:
The phase behavior and solubility relations of the benzene‐water system
Authors: Rebert Charles J. , Kay Webster B. 
Published: June 2004

AbstractIn order to contribute to knowledge of the nature of the phase behavior of partially miscible liquid systems, a study of the benzene‐water system was undertaken. The pressures at liquid‐ and vapor‐phase boundaries of fifteen mixtures of benzene and water were determined within the temperature range of 200 to 357°C. Along with a complete numerical tabulation, these data are presented graphically as pressure‐temperature, pressure‐composition, and temperature‐composition phase diagrams to show the nature of the boundaries.Up to the three‐phase critical end point, the benzene‐water system develops in a manner usually ascribed to a partially miscible system in which the vapor compositin at a point of univariance lies intermediate to the two liquid compositions. The three‐phase critical end point occurs at 1,364 1b./sq. in. abs. and 268.3°C., and the composition of the critical phase is 25.8 weight % water, with the remaining liquid phase 92.8 weight % water.The pressure, temperature, and composition of the critical solution end point are deduced as 2,300 1b./sq. in. abs., 306.4°C., and 59 weight % water, respectively. At temperatures between these two critical points the phase behavior is likened to that of a dense gas or fluid dissolved in a liquid. Definite limiting values of temperature and pressure are assignable to this behavior by the extension of the three‐phase curve up to the critical solution end point. This extended curve is not a phase boundary, but the temperature and pressure at a given point on the curve represents in a mixture of fixed composition the limit of mutual solubility of the benzene‐rich fluid phase and the water‐rich phase. At a temperature above or a pressure below the given point the liquid phase begins to vaporize.Above the critical solution end point the vapor‐liquid phase boundaries are like those of a normal binary mixture.
Multicomponent distillation on a large digital computer: II. Generalization with side‐stream stripping
Authors: Amundson N. R. , Pontinen A. J. , Tierney J. W. 
Published: June 2004

AbstractThe problem of multicomponent distillation is considered for a column with an arbitrary number of feed streams and an arbitrary number of side‐stream withdrawals. The overheads from the side‐stream strippers are admitted to the column, introducing the inert stripping medium into the main column. Provisions are made in the calculations for complete heat balancing, inert injection, and internal reflux cooling. The method of computation is that of a previous paper involving the component‐by‐component technique. Calculations are made on the main column and give first approximations to the side‐stream compositions; stripper calculations are then initiated. An alternating procedure is instituted between the main column and the strippers, the successive iterations continuing until a preassigned accuracy in the desired quantities is reached. An extensive numerical problem is worked.
Formation of gas bubbles at submerged orifices
Authors: Hayes W. B. , Hardy B. W. , Holland C. D. 
Published: June 2004

AbstractThe formation of air bubbles at constant pressure at submerged orifices was investigated for several liquids. The frequency of formation of the bubbles was determined by the use of a stroboscope, and the rate of gas flow was measured with conventional rotameters. Several orifices having diameters ranging from 0.0794 to 0.397 cm. were employed, and the gas flow rate was varied from about 0.1 cc. (at standard conditions)/sec. to about 150 cc./sec. It was found that the formation of bubbles could be correlated with the physical variables of the system by the application of Newton's second law of motion to the bubble at the instant just prior to its release from the orifice.
Diffusion‐controlled chemical reactions
Authors: Toor H. L. , Chiang S. H. 
Published: June 2004

AbstractTransformation are obtained which reduce the system of differential equations for certain types of diffusion‐controlled reactions to the equation for pure diffusion.Simple relationships between the diffusion rate with and without reactions are presented for reversible unimolecular reactions, certain types of reversible bimolecular reactions, and irreversible reactions between species with equal diffusivities. It is shown that these relationships are independent of geometry, hydrodynamics, or boundary conditions, and so the mass transfer coefficient in the presence of reactions can be obtained from the coefficient in the absence of reactions without an explicit knowledge of the mass transfer mechanism.The reaction factor for irreversible reactions with equal diffusivities, obtained by others for specific mass transfer mechanisms, is found to be quite general and essentially independent of the mechanism.Some data on the absorption of sulfur dioxide in a laminar water jet is considered.
Mechanism of drying thick porous bodies during the falling‐rate period: II. A hygroscopic material
Authors: Bell J. R. , Nissan A. H. 
Published: June 2004

AbstractA further analysis of the second falling‐rate period in the drying of thick highly porous textile structures is made, this time in the case of drying wool, special attention being paid to the adsorbed water held by the wool in the air‐dry region. As the solid‐to‐void ratio is low, the quantities of adsorbed water are small and have little effect on the general equilibrium. Values of thermal conductivity are calculated for wet wool.
Vinyl chloride from acetylene and hydrogen chloride: Catalytic‐rate studies
Authors: Wesselhoft R. D. , Woods J. M. , Smith J. M. 
Published: June 2004

AbstractThe reaction rate of gaseous acetylene and hydrogen chloride was studied experimentally on a mercuric chloride–activated carbon catalyst at pressures from 1 to 4 atm. and temperatures of 167°, 212°, and 257°F. The measurements were made in a differential reactor packed with mercuric chloride impregnated on activated carbon, the data being taken to obtain the separate effect of the partial pressure of each of the components on the rate.The results indicated that hydrogen chloride was strongly adsorbed on the catalyst and that vinyl chloride was also adsorbed to a significant extent. A rate equation, which well represented the data, was developed from the following postulates: (a) acetylene is adsorbed on the catalyst on one type of site, (b) hydrogen chloride and vinyl chloride are adsorbed on a different kind of site, (c) the formation of vinyl chloride occurs by reaction of adsorbed acetylene and adsorbed hydrogen chloride, and (d) the rates of adsorption and desorption are fast compared with the formation rate of vinyl chloride.
Thermal conductivity of diatomic gases: Liquid and gaseous states
Authors: Schaefer Charles A. , Thodos George 
Published: June 2004

AbstractAfter an extensive literature survey the experimental thermal‐conductivity data for twelve diatomic gases were utilized to produce an accurate and expedient means of predicting values over extensive ranges of temperature and pressure. Plotting values ofk* againstTRon logarithmic coordinates produced similarities pointing to the existence of corresponding states behavior for this family of substances with the exception of hydrogen. Because hydrogen cannot be included in a correlation generalized for the diatomic gases, it has been eliminated from this study. Based on atmospheric pressure data, ratios ofk*/k*Tcproduced a unique relationship with reduced temperature. To include the effect of pressure, residual thermal conductivities were correlated with density for nitrogen and oxygen, the only substances for which high‐pressure data exist. These relationships enabled the determination of the thermal conductivity at the critical point. When the valuekc= 8.55 × 10−5cal./sec. cm. °K. for nitrogen was used, au extensive reduced thermal‐conductivity correlation was constructed against reduced temperature for parameters of constant reduced pressure. This chart, extending to reduced pressures of 100 and to reduced temperatures of 85, is recommended for the diatomic gases in their gaseous and liquid states.The developed correlation reproduces experimental nitrogen data to within 1.39%. For the other diatomic gases experimental agreement extends from 1.00 to 3.20%. Such agreement indicates that this correlation is more reliable for the diatomic gases than are other generalized plots presented in the literature.
Theory of solvent extraction of phosphoric and hydrochloric acids
Authors: Seaton W. H. , Geankoplis C. J. 
Published: June 2004

AbstractMixtures of hydrochloric and phosphoric acids were extracted from aqueous solution by organic solvents in a study to advance the theories of solvent extraction.Four solvents, t‐amyl alcohol, n‐butanol, cyclohexanol, and 2‐hydroxyethyl, n‐hexyl ether, were found to give high distribution coefficients of 0.1 to 0.5 for both acids. In studies using the ether type of solvent an increase of the pH of the aqueous phase from 0 to 10 reduced the distribution ratio of phosphoric acid by a factor of 1,100.The substitution of hydriodic acid for hydrochloric caused a 42% increase in the K of phosphoric acid, which could indicate the importance of internal pressure of the additive in extraction. Measurements of activity coefficients of the hydrochloric acid in aqueous solution showed only a 1% increase in its activity coefficient with addition of large amounts of phosphoric acid. This could not be sufficient to cause up to a 40% increase in the distribution coefficient of the hydrochloric acid with the addition of the phosphoric acid.
Solid‐catalyzed reaction in a fluidized bed
Authors: Lewis W. K. , Gilliland E. R. , Glass Werner 
Published: June 2004

AbstractResults are presented for the solid‐catalyzed hydrogenation of ethylene in fixed and fluidized beds. The effect of gas velocity, bed height, catalyst activity, particle size, and internal baffles on fluidized reactor efficiency are given, and Equations derived from a simplified mathematical model correlate the data.
Void fractions in two‐phase flow
Authors: Isbin H. S. , Rodriguez H. A. , Larson H. C. , Pattie B. D. 
Published: June 2004

AbstractVoid fractions (fraction of the flow cross‐sectional area occupied by the gas phase) have been measured for steam‐water flows in an adiabatic, horizontal test section of 0.484 in. I.D. at 400, 600, 800, and 1,000 1b./sq. in. gauge. A comprehensive survey of void data for two‐phase concurrent flow is included in the paper, and the data, including the Martinelli and homogeneous flow model predictions, are compared. System characteristics, involving one‐ and two‐component flows in horizontal and vertical test sections with and without heat transfer over a range of flow ratios, total flow rates, and pressure, are too complex, and the data available are neither extensive nor precise enough to warrant the generation of over‐all correlations. Use of the void data in correlating two‐phase frictional pressure drops is discussed. A model has been presented for the prediction of critical flows based upon the void data, and calculations have been made for steam‐water critical flows over a range of critical pressures from 15 to 2,000 1b./sq. in. abs.
Performance of a reciprocating‐plate extraction column
Authors: Karr Andrew E. 
Published: June 2004

AbstractAn open type of reciprocating‐plate extraction column was developed, and it is proposed that the scaling up of such a column should be straightforward; that is, the height of an equivalent theoretical stage (H.E.T.S.) and the throughput per unit area should be independent of the diameter of the column.Plates having 5/8‐in.–diameter holes and 62.8% free space were selected to minimize the resistance to countercurrent flow in the column. With this design low H.E.T.S. values were achieved at throughputs much higher than those reported for other columns. Thus for two systems the present column was shown to require the lowest volume of column to accomplish a given extraction job. Data were obtained in a 3‐in.–diameter column on two systems, methyl isobutyl ketone‐acetic acid‐water and o‐xylene‐acetic acid‐water. Throughputs studied on the first system ranged from 547 to 1,837 gal./hr./sq. ft., and the corresponding minimum H.E.T.S. values achieved were 4.3 and 7.5 in. respectively. For the second system minimum H.E.T.S. values of 7.7 and 9.1 in. were attained at throughputs of 424 and 804 gal./hr./sq. ft. respectively.Extraction column design procedures are discussed. The fabrication of the reciprocating‐plate column is relatively simple, and this should encourage its use first in pilot‐scale sizes and ultimately in large‐scale columns.
Kinetics of the hydrogenation of ethylene: (On a nickel catalyst)
Authors: Pauls A. C. , Comings E. W. , Smith J. M. 
Published: June 2004

AbstractA differential type of flow reactor, 0.25‐in. I.D., was used to study the kinetics of the hydrogenation of ethylene on an alumina‐supported nickel catalyst. This is apparently the first investigation made above atmospheric pressures. Data were obtained from 14.7 to 70 1b./sq. in. abs. and feed compositions from 40 to 90 mole % hydrogen. Measurements at temperatures from 30° to 80°C. indicated an apparent activation energy of 11,600 cal./g.‐mole.It was found that the activity of the catalytic surface was reduced by exposure to ethylene, or mixtures containing an excess of ethylene, owing to the formation of acetylene residues. Pretreatment of the catalyst at temperatures of 170°C. with mixtures of ethylene and hydrogen stabilized the catalyst so that reliable rate data could be obtained.The rate measurements at 70°C. were correlated by an equation. While the mechanism of the reaction cannot be determined from the data, the rate expression and other kinetic studies suggest a process in which hydrogen is adsorbed on the small fraction of the surface not occupied by acetylenic residues and the reaction takes place between this adsorbed hydrogen and ethylene in the gas phase.
Interfacial turbulence: Hydrodynamic instability and the marangoni effect
Authors: Sternling C. V. , Scriven L. E. 
Published: June 2004

AbstractThe origin of interfacial turbulence, spontaneous agitation of the interface between two unequilibrated liquids, has been explained in terms of classical flow, diffusion, and surface processes. The essence of the explanation is the long‐known though much neglected Marangoni effect, wherein movement in an interface is caused by longitudinal variations of interfacial tension. It is proposed that interfacial turbulence is a manifestation of hydrodynamic instability, which is touched off by ever present, small, random fluctuations about the interface.A simplified mathematical model has been analyzed in order to detail the mechanism of the “interfacial engine” which supplies the mechanical energy of interfacial turbulence. In its present form the analysis incorporates several drastic simplifications, though ways of removing some of these have been suggested. The groundwork has been laid for the more elaborate analyses that are needed for a decisive test of the theory.The analysis shows how some systems may be stable with solute transfer in one direction yet unstable with transfer in the opposite direction, a striking result. It also suggests that interfacial turbulence is usually promoted by (1) solute transfer out of the phase of higher viscosity, (2) solute transfer out of the phase in which its diffusivity is lower, (3) large differences in kinematic viscosity and solute diffusivity between the two phases, (4) steep concentration gradients near the interface, (5) interfacial tension highly sensitive to solute concentration, (6) low viscosities and diffusivities in both phases, (7) absence of surface‐active agents, and (8) interfaces of large extent.That some of these effects have been observed in the laboratory lends credence to the theory.
Heat and mass transfer in spray drying
Authors: Dlouhy Jan , Gauvin W. H. 
Published: June 2004

AbstractStudies of the evaporation and drying rates in an experimental concurrent spray dryer, 8 in. in diameter and 14 ft. high, are reported for various operating air temperatures. It was found that the total evaporation and drying time could be accurately predicted by employing a step‐by‐step method of calculation. Owing to the probable absence of internal diffusional resistance in the small particles, less than 30 μ, produced in the dryer, no significant falling‐rate period was observed. This was in marked contrast with tray‐drying experiments carried out on the same substance, under similar drying conditions. The results also confirmed that a Nusselt number of 2 can safely be used in spray‐drying heat transfer calculations.
The critical constants of the elements
Authors: Gates David S. , Thodos George 
Published: June 2004

AbstractThe critical temperatures available in the literature for seventeen elements constitute the basis of this study for predicting critical temperatures from normal boiling points. When not available, the normal boiling point can be estimated from vapor‐pressure data. The extension of the vapor‐pressure data beyond the normal boiling point establishes the critical pressure from the estimated critical temperature.In accordance with this procedure, critical temperatures and pressures have been predicted for thirty‐six elements included in the periodic table from lithium to uranium. These critical constants consitute the core of this study and have been used to calculate both van der Waals' constants. These constants, when plotted against their atomic numbers, produce correlations that may permit the further prediction of van der Waals' constants for other elements.A simple relationship between the critical volume and the volume van der Waals' constant is found to exist and is presented as a basis for predicting the critical volume of elements.
Effect of a cylindrical boundary on a fixed rigid sphere in a moving viscous fluid
Authors: Fayon A. M. , Happel John 
Published: June 2004

AbstractIn this investigation of the effect of a cylindrical boundary on a spherical particle suspended in a moving viscous fluid the pressure drop due to the motion of fluid past a stationary sphere and the drag on the sphere are independently measured, and the sphere‐ to‐cylinder‐diameter ratios varying from 0.1250 to 0.3125 are studied at different positions of eccentricity. The investigation shows that in the range of Reynolds numbers from 0.1 to 40.0, based on the approach velocity to the sphere and the diameter of the sphere, the pressure drop due to the presence of a sphere and the drag on it can be represented by a semiempirical relationship containing two terms. One term, owing to the effect of the cylindrical boundary, is derived theoretically from the creeping‐motion equations which neglect inertial effects. The second term, owing to the inertial effects, is established from data on the drag coefficient of a sphere in on unbounded medium.
Detonation characteristics of hydrogen‐oxygen mixtures
Authors: Moyle Morton P. , Morrison Richard B. , Churchill Stuart W. 
Published: June 2004

AbstractDetonation velocities were measured in mixtures of hydrogen and oxygen containing 25 to 75 mole % hydrogen at initial temperatures from 160° to 580°K. and initial pressures from 1/2 to 2 atm. The measurements were made in a number of tubes of different diameter to permit extrapolation to a tube of infinite diameter. Theoretical detonation characteristics were computed for the same range of conditions. The measured and computed velocities are in good agreement except in rich mixtures and at subatmospheric pressures. Schlieren photographs reveal that the detonation wave front is very thin for a stoichiometric mixture but degenerates to a complicated zone of interacting shock waves and turbulent combustion as the percentage of hydrogen is reduced. The detonation velocity is found to depend only slightly on initial temperature and pressure. The computed pressures behind the detonation and reflected waves are roughly proportional to initial pressure and to the reciprocal of the initial temperature.
Studies on heat transfer near wall surface in packed beds
Authors: Yagi Sakae , Kunii Daizo 
Published: June 2004

AbstractFrom studies of annular packed beds wherein the heat flows purely radially, the authors obtained the coefficients of heat transfer on the inner tube surface, as well as the mean effective thermal conductivities of bed. The inner and outer diameters of the annular packed bed were 22 and 70 mm. respectively, and the packings shown in Table 1 were used. The wall film coefficients obtained with air flowing axially through the bed were correlated for NReM < 600 by means of Equation (14).The coefficients of heat transfer for cylindrical packed beds reported previously by other observers were correlated also by Equation (14), with 0.054 used for values of αω in the range NReM < 2,000.Consideration of Equation (14) in terms of a theoretical model of heat transfer showed that it was reasonable to apply it for the prediction of wall film coefficient, especially for low Reynolds numbers.
Mechanics of particle bounce
Authors: Ranz W. E. , Talandis G. R. , Gutterman Bernard 
Published: June 2004

AbstractIrregular particles bounce with randomly distributed angles of reflection. There is a certain probability that a particle striking at low angle will bounce at a high angle and be carried far out into the main fluid flow. Bounce phenomena were investigated with respect to bounce of a model particle, limitations on dust collection (back mixing), and energy loss during the flow of suspensions.
Compressibility and vapor pressure of methyl borate
Authors: Griskey Richard G. , Gorgas Walter E. , Canjar Lawrence N. 
Published: June 2004

AbstractPressure‐volume‐temperature measurements have been made on methyl borate over the temperature range of 2257deg; to 300°C. and pressures of 30 to 200 atm. in a variable volume P‐V‐T bomb. Vapor‐pressure measurements from 180°C. to the critical point have also been made with the same apparatus. The vapor‐pressure data are presented in the form of the Antoine equation, and the P‐V‐T data together with the vapor‐pressure data have been fitted to the Benedict‐Webb‐Rubin equation of state.
The motion of two spheres following each other in a viscous fluid
Authors: Happel John , Pfeffer Robert 
Published: June 2004

AbstractThe purpose of this investigation was to determine the interaction effect of one spherical particle upon another when both are falling in a viscous fluid. The velocities of two identical spheres, falling along the axis of a cylinder in a direction parallel to their line of centers, were measured experimentally as a function of the center‐to‐center distance between them at very low Reynolds numbers. The experimental results compared very well with theoretical studies found in the literature which predicted that two spheres will fall faster than one sphere.At Reynolds numbers greater than 0.25 the influence of inertial effects were studied for one end two spheres. The experimental results qualitatively confirmed the Oseen equations. A definite attraction between two spheres falling one above the other was observed; the inertial forces acted to slow down the lower sphere without affecting the upper one.
Mass transfer inside drops
Authors: Johnson A. I. , Hamielec A. E. 
Published: June 2004

AbstractThe transfer rates of n‐butanol, cyclohexanol, and ethyl acetate into water drops have been measured for circulating and oscillating drops.Methods of allowing for the end‐effect transfer have been extended and measured values compared with predictions of a model.Various mechanisms for transfer inside drops have been examined in terms of a correlation factor.