BENEFITS OF A COÖRDINATED PROGRAM OF CERAMIC INVESTIGATIONS BY FEDERAL,STATE, AND UNIVERSITY AGENCIES1

The rapid development of ceramic technology is necessary to the well-being of our industry. A comprehensive plan should be laid out and the required machinery, responsible to the manufacturers, set up to accomplish this.     

FUNDAMENTAL STUDY OF CLAY: VI,FLOW PROPERTIES OF KAOLINITE-WATER SUSPÉNSIONS*

The flow properties of six monodisperse kaolinite fractions were studied over a large range of concentration. From these results, it has been possible to set up an equation relating viscosity to concentration which holds over a very wide range. Equations relating concentration to thixotropy and to the yield point which have general application could also be established. The viscosity of a suspension is obtained from the sum of three quantities, namely, those contributed by (1) the liquid, (2) the individual particle, and (3) the collisions of the particles. Thixotropy is found to be due to the sum of two quantities, namely, the contribution of (1) the individual particle and (2) the interference of the particles. The yield point in these fractions was found to be proportional to the cube of the concentration. With these relations, it is possible to calculate the viscosity of a casting slip for any change in specific gravity.     

PHYSICAL CHEMISTRY OF ADSORPTION OF COPPER,NICKEL AND COBALT ON LIGNITE FROM AMMONIACAL SOLUTIONS

The adsorption of Me(metal),NH_3 and CO_2 on lignite from ammoniacal solution containing metallicions such as Cu,Ni,and Co was investigated.Preliminary mechanism studied revealed that active carboxyland phenolic groups of humic acid in lignite as well as surface adsorption were involved.The rate of ap-proach to adsorption equilibrium on lignite was NH_3>Ni>Co>Cu andthe adsorption on lignite is Cu>Co>Ni>NH_3.The order of selective elution was NH_3>>Ni,Co>Cu.All metals were fully stripped and NH,could only be recovered partially.NH_3 adsorbed on lignite fron metal-ammoniacal solution is easily lost by volatilization,only a smallfraction remaining on lignite at a temperature of 120℃.CO_2 adsorbed physically in nature from ammonia-cal solution with a capacity of less then one percent was observed under the practical conditions generallyin hydrometallurgy.     

DETERMINATION,CORRELATION AND PREDICTION OF LIQUID-LIQUID EQUILIBRIUM DATA OF n-BUTYL ALCOHOL-WATER-BUTYL ACETATE TERNARY SYSTEM

Liquid-liquid equilibrium(LLE)data have been determined for the n-butyl alcohol-water-butyl acetateternary system and the related binary systems at 293.15,303.15 and 313.15 K.The experimentally determinedLLE data for the n-butyl alcohol-water binary system have been found to be in satisfactory agreementwith the available literature data.The correlation and prediction of the LLE data have been done byusing NRTL and UNIQUAC models.The model parameters of binary systems have been identified witha thermodynamic criterion.In the correlation of ternary LLE data,two objective functions(mole fractionand distribution constant)have been used for purpose of comparison.The effect of weighting in the firstobjective function has been examined.In predicting the ternary LLE with different sets of parameter valuesobtained for each of the constitutent binary systems,improved prediction results have been obtained bycomparing the results of different combinations of the sets of parameter values and choosing those givingthe best result.     

SOLUBILITY OF LAMOTRIGINE IN BINARY AND TERNARY MIXTURES OF PEGS 200, 400, AND 600 WITH ETHANOL,PG, AND WATER AT 298.2 K

Experimental solubilities of 6-(2,3-dichlorophenyl)-1,2,4-triazine-3,5-diamine (lamotrigine) in binary and ternary solvents of polyethylene glycols (PEGs) 200, 400, and 600 with ethanol and water, and PEGs 200, 400, and 600 with propylene glycol (PG) and water at T = 298.2 K are reported. The Jouyban-Acree model was used to fit solubility data of lamotrigine in the binary and ternary solvent mixtures (145 data points) in which the overall mean relative deviation (OMRD %) was 11.5%. The density of the solute-free solvent mixtures was measured and employed to calculate the constants of the Jouyban-Acree model and then the density of the saturated solutions is predicted.     

VAPOR-LIQUID EQUILIBRIUM FOR TERNARY MIXTURES OF BENZENE,TOLUENE,AND p-XYLENE

Vapor-liquid equilibrium composition and temperature were measured for binary andternary mixtures of benzene,toluene and p-xylene at 101.33 kPa The equilibrium cell of Boubliketal.was modified for the present study.The experimental vapor-liquid equilibrium data were corre-lated with the Wilson equation.     

HYDRODYNAMIC CHARACTERISTICS OF THE PROCESS OF DEPRESSURIZATION OF SATURATED WATER

Experiments were carried out to find the effects of dissolved gas pressure,liquid flow rateand nozzle geometry on the bubble generation when saturated water was depressurized through anozzle.A new method,high speed camera system was developed to measure the generated microbubblesdynamically.On the basis of the laws of ideal gas and solution,theoretical generated gas flow ratewas deduced,while the Smoluchowski′s equation was applied to describe the kinetics of bubblenucleation.It was found that the size distribution of nucleated bubbles was of skewed distribution.An explanation to this phenomenon was made and the Gamma function distribution was employedfor mathematical simulation.The results show good agreement between the experimental data and thepredictions by proposed model.     

CHEMOSELECTIVE PREPARATION OF CHLOROSULFONYL-CONTAINING AZO-DYES WITH THIONYL CHLORIDE-N, N-DIMETHYLFORMAMIDE

Azo- dyes containing chlorosulfonyl group are important intermediates of dyes for use in instant photography and sulfonamido - containing disperse dyes. Chlorination of azo-dyes containing sulfonic acid group to the corresponding sulfonyl chlorides is an important method for the synthesis of this kind of     

THE CALCULATION OF CRITICAL PROPERTIES OF MIXTURES FROM EQUATIONS OF STATE

The rigorous critical state criteria based on Helmholtz free energy is used with equations of state fordirect calculation of critical properties(T_c,P_c and V_c)of 44 binary and 5 ternary systems.Special at-tention is paid to systems containing polar component(s)and the improvement in critical volume prediction.For extending this method to polar systems,the recently developed Cubic Chain-of-Rotators equation ofstate has been applied.As compared with SRK and PR equations of state,the improvement in V_c pre-diction is most impressive.     

DENSITIES AND DERIVED THERMODYNAMIC PROPERTIES OF THE BINARY SYSTEMS OF BENZENE WITH BUTYL METHACRYLATE,ALLYL METHACRYLATE,METHACRYLIC ACID,AND VINYL ACETATE AT 298.15 K

Densities of the binary systems of benzene with butyl methacrylate, allyl methacrylate, methacrylic acid, and vinyl acetate have been measured as a function of the composition, at 298.15 K and atmospheric pressure, using an Anton Paar DMA 5000 oscillating U-tube densimeter. The calculated excess molar volumes were correlated with the Redlich-Kister equation and with a series of Legendre polynomials. The excess molar volumes are positive for the four binaries studied.     

SUBSTITUTION OF TOPAZ,DOMESTIC KYANITE,AND SYNTHETIC MULLITE-CORUNDUM FOR INDIA KYANITE,I–III*

This report on the utilization of domestic materials as replacements for India kyanite has been divided into four parts, namely, (I) kyanite and other high-grade refractories, (II) effect of heat on kyanite and topaz, and (III) load resistance of refractories at elevated temperatures; (IV) will be published later.     

SYNTHESIS, CHARACTERIZATION AND APPLICATION IN PEMFC OF ZIRCONIUM OXO PHOSPHATE-SULFATE

Mesoporous zirconium oxo phosphate-sulfate was synthesized by hydrothermal method with hexadecyltrithylammonium bromide(CTAB)as the template and with zirconium nitrate or zirconium oxychloride as zirconium source.The optimum two-stage process was established, ~(31)P MAS NMR showed that the states of phosphate species were changed with further postsynthesis treatment by sulfate acid. The transformations of the structures at different temperatures from room temperature to 1173 K were investigated by XRD. The mesoporous structure could be retained up to 723 K. The proportion of tetragonal phase (T-ZrO_2) to monoclinic phase (M-ZrO_2) decreased with increasing temperature from 923 K to 1173 K. After the as-synthesized sample was treated by H_3PO_4 and H_2SO_4, T-ZrO_2 kept predominant at wide temperature range. The performance of proton exchange membrane fuel cell (PEMFC) with the recast composite membrane of Nafion and zirconium oxo phosphonate-sulfurate has been investigated.     

SOLUBILITY OF ACETAMINOPHEN AND IBUPROFEN IN BINARY AND TERNARY MIXTURES OF POLYETHYLENE GLYCOLS 200 AND 400, PROPYLENE GLYCOL,AND WATER AT 25°C

The solubilities of acetaminophen and ibuprofen in the mixtures of propylene glycol-water, polyethylene glycols 200- and 400-propylene glycol, and polyethylene glycols 200- and 400-propylene glycol-water (122 data points) at 25°C were determined and mathematically represented by the Jouyban-Acree model. The solubilities were measured using the shake flask method, and the model was used to fit the solubility data of each drug in the solvent mixtures. The density of the solute-free solvent mixtures was measured and the density of the drug-saturated solutions was predicted. The obtained overall mean relative deviations (OMRDs) for fitting the solubility data of acetaminophen and ibuprofen in binary mixtures are 1.5% and 11.7%, respectively. The OMRDs for fitting the solubilities in ternary solvent mixtures for acetaminophen and ibuprofen are 16.3% and 42.0%, respectively, and the OMRD values for predicting all solubilities of acetaminophen and ibuprofen by these trained versions of the Jouyban-Acree model were 5.7% and 20.4%, respectively. The prediction OMRD for the density of saturated solutions was 2.5%.     

CALCULATION OF THERMODYNAMIC PROPERTIES OF FLUID MIXTURES WITH A NEW EQUATION OF STATE †

The subject of this paper is the evaluation of the applicability of constant temperature anemometry (CTA) with a modified version of Delhaye's method to aerated stirred tanks. A calibration technique that takes into account the variation in medium temperature was developed and verified experimentally. The directional sensitivity of the conical film probe was investigated in a streamline flow field as well as in the impeller discharge stream in an stirred tank.

The reliability of the setup and the technique was verified through the comparison of the vertical and radial velocity profiles of water in a stirred tank with those obtained from the literature. The directional response of the conical probe follows the cosine law for intersection angles smaller than 45° in a streamline flow field, but the directional sensitivity in the impeller discharge stream is rather poor, owing to the rolling characteristics of flow in this region. Due to the inability to detect bubbles smaller than the sensing element of the conical probe, the CTA usually gives lower values of local gas holdup. However, this discrepancy is considered to have no influence on the velocity measurement.     

STUDY OF FACTORS INVOLVED IN GLAZE-SLIP CONTROL,I–IV* I,GLAZE-SLIP SPECIFICATIONS

Experiments were conducted to find a simple, adequate means of specifying glaze consistency. Tests showed that the amount of slip clinging to a glass plate after it is withdrawn from a reservoir of slip (known as its coherence value) was directly influenced by such factors as amount of water, clay content, and age. These factors are commonly thought of as governing the working quality of the slip. Surface tension has little apparent relation to the working qualities of the slip. Examination of the fired glazes revealed that a distinct coherence value separated good glazes from poor types. A total of 110 pieces was fired; of these samples, fifty-two were glazed with slips having coherence values above 0.04 gm. per sq. cm. Only three of the fifty-two samples were satisfactory; the remaining fifty-eight were coated with slips with a coherence value of less than 0.04 gm. per sq. cm. Only nine of these were defective in any respect and most of them were in the region of 0.04 gm. per sq. cm. coherence value.     

LIQUID-LIQUID EQUILIBRIA OF ORGANIC COMPOUNDS: MEASUREMENT,CORRELATION AND PREDICTION†

The knowledge of phase equilibria is an important step in the development of extraction processes. This knowledge is usually gained from experiments. However, this procedure is expensive when a suitable solvent has to be found for a specific separation. Therefore methods for predicting phase equilibria are needed. While formerly these methods were largely based on empirical assumptions, the use of the concept of local compositions by Wilson⁶ offers a semi-empirical approach.

There is one disadvantage of this approach: the parameters of models like UNIQUAC or NRTL have to be fitted to different types of data, to liquid-liquid equilibria (LLE) for the immiscible pairs of components and to vapour-liquid equilibria (VLE) or other data for the miscible pairs in a system with mutual solubility.

To demonstrate the problem we performed measurements in the binary systems: n-octane/aniline and methylcylohexane/aniline. of both liquid-liquid equilibrium and vapour-liquid equilibrium: for the second type of measurements ebulliomeiry was used. The prediction of LLE has been improved with two new concepts. One is based on the well-known UNIFAC method. The use of the Lyngby-Dorlmund data bank made it possible to determine a new parameter table merely based on LLE data.

The second method is based on common UNIQUAC parameters which have been determined with the data base.