Model of heterogeneous hydrodynamic coagulation of microdrops

The Eley-Rideal and Langmuir concepts of surface reactions were used to develop a model of heterogeneous hydrodynamic coagulation of diluted “oil-in-water” emulsions (0.1–2.0 vol %). The mathematical model was verified, and factors that govern the coagulation rate were revealed.     

Equilibrium of trivalent iron sorption by activated carbons in the presence of an equimolar amount of disodium salt of ethylenediaminetetraacetic acid from aqueous solutions at pH 1–3

Dependences of the equilibrium adsorption capacity of FAS-Z, AG-3-O, and KAD-iodine activated carbons for iron at pH 1, 1.5, 2, and 3 in the presence of equimolar amounts of trivalent iron and disodium salt of acid in the starting aqueous solution were determined.     

Dehydration of Organic Solvents by Evaporation through Membranes Based on Polyelectrolytic Complexes

Evaporation of binary aqueous-organic mixtures through composite membranes with coatings based on polyelectrolytic complexes including different combinations of polyelectrolytic polycations and polyanions was studied. The possibility of efficient dehydration of organic solvents by their pervaporation was demonstrated.     

Influence of pH of solution on phase composition of samarium-strontium cobaltite powders synthesized by wet chemical technique

Powders of Sm_0.6Sr_0.4CoO_3-δ and La_0.6Sr_0.4CoO_3-δ were synthesized using wet chemical technique. Structural and surface properties of synthesized materials were studied by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), IR spectroscopy, and scanning electron microscopy (SEM). The influence of pH on the phase state, chemical composition, morphology, and fractal dimension of the synthesized powders were investigated. It was found that the change of pH has the influence on phase composition of synthesized powders. The increase of solution pH allows one to obtain homogeneous samples at lower temperatures down to 900–950?°C.

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Pervaporation Membranes for Separating Mixtures of Methanol and Methyl tert-Butyl Ether

Transport characteristics of new types of bi- and multilayer composite polymer pervaporation membranes and asymmetrical membranes in separating mixtures of methanol and methyl tert-butyl ether were studied. The principles of design of the membranes and their mass-exchange characteristics are treated in terms of the Henis-Tripodi resistance model.     

Kinetics of heterogeneous hydrodynamic coagulation of microscopic drops

A prototype reactor for heterogeneous hydrodynamic coagulation of emulsions was developed and tested. The efficiency of coagulation of water emulsions of some organic liquids was studied in relation to process conditions.     

Effect of diluent additives on the rate of water purification to remove microdrops of tri-n-butyl phosphate by hydrodynamic heteroadagulation

Effect of diluents on the coarsening of microdrops of tri-n-butyl phosphate by hydrodynamic heteroadagulation on a carbon fabric in water was studied.     

Transport properties of cellulose ester membranes for separating gas and liquid mixtures

Mass-exchange characteristics of cellulose myristate or acetomyristate membranes in separating aqueous-organic, organic, or gas mixtures, particularly, in recovering aromatic hydrocarbons from binary mixtures with aliphatic alcohols, and also ethyl acetate from a mixture of esterification products, are studied.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 11, 2004, pp. 1895–1900.Original Russian Text Copyright © 2004 by Yu. Kuznetsov, Khripunov, Kruchinina, V. Kuznetsov, Turkova, Penkova.     

Prediction of separating characteristics of pervaporation membranes by inverse gas chromatography

The potentiality of inverse gas chromatography to predict separating properties of pervaporation membranes is studied for the example of a membrane composed of a mixture of polyvinyl alcohol and polyacrylic acid. Correlation relationships between the retention time of substances and relative rate of their mass transfer across the membrane were derived. A comparative method for assessment of the membrane selectivity was suggested proposed, and its consistency was checked for pervaporation separation of methanol-methyl acetate-water-acetic acid, methanol-toluene, and ethanol-ethyl acetate mixtures, including those with an azeotropic composition.