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The extraction mechanism has been considered and the crucial role of the dynamic interfacial layer has been noted. The microprocesses that take place in extraction systems and are associated with the Marangoni effect, the loss of hydrodynamic stability, partial dispersion, coalescence, flocculation, the Ostwald ripening of drops, chemical reactions, the emergence of a new phase, adsorption, coagulation, the formation of structures, and polymerization have been described. For LnCl3–H2O–diluent systems (heptane, toluene, tetrachloromethane), data on the shift in the boundaries of the observed transition region over time have been presented. The mechanism of the transfer of the substance in the transition region of the extraction system has been formulated.

The statistical parameters of hydrodynamic heteroadagulation of microdrops of solar oil with sizes of 0.5–2 μm have been obtained for the first time. The problem is of a great practical significance because the agglomeration of microdrops leads to substantial acceleration of purification of aqueous phase from them according to hydrodynamic heteroadagulation (HHA). HHA has been studied in the broad range of the rotation frequencies of rotor discs from 200 to 2000 min−1. Root-mean-square deviations S have been calculated in all points of kinetic curves and also their relative errors δ% have been obtained. The methods of analyzing the u-distributions and Student t-distributions have been used. The trends of random deviations of kinetic curves of heteroadagulation from mean values have been determined.

The process of the microdrop coarsening of KhA-30 compressor oil on carbon fabric is studied. The problem is connected with the necessity of the cleaning of air and water from the microdrops of oils cooling the compressors. The heteroadagulation method allowed for the separation of water from compressor oil particles with a diameter 0.8–7.6 μm over the course of a few minutes. The oiling of the carbon fabric is reduced to a minimum. For the first time, by an order of magnitude, finer discontinuities, which can behave as stable cluster origination centers, are observed on the surface of micron-sized oil drops.

We consider the hydrodynamic heteroadagulation method for water purification from microdrops of organic liquids with a size of 0.8–10 μm and concentration of 0.02–2.0%. A mathematical model of the process is proposed. The role of material for heteroadagulation, the rotation frequency of dispenser rotors and heteroadagulator mixer, and the pH level were discussed. Purification from microdrops is ascertained to be ∼93–99% fulfilled over 5–25 min. We reveal and interpret the reason for aliasing of kinetic curves of heterodynamic heteroadagulation and its appreciable acceleration or deceleration upon the introduction of a second set of drops larger than the first by a factor of 300–500.

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

Reaction kinetics of ozone destruction in water in the presence of an anion and a cation impurity has been examined. Cromates and, possibly, a complex anion of iron with a valence of three have the strongest catalytic property among all tested anions. Cations do not influence the reaction rate of ozone destruction.

Coalescence of KHA-30 compressor oil microdroplets on a carbon fabric, aimed to remove them from air and water streams used for compressor cooling, was examined.

The kinetics of the spreading of polymolecular films are studied. It is shown that they move slower than monomolecular films with the polar liquid Midel 7131 moving especially slowly. The cause of the considerably slower motion of surfactants is explained.

The linearization of kinetic curves of the decoloration of direct green and methylene blue dyes and humic acids is performed. It is shown that the kinetic curves can be linearized in the time-square root of the negative logarithm of reduced optical light absorption or ozone concentration coordinates. This provides a simple way of modeling and optimizing ozonation processes.

The problem of purifying water from microscopic oil drops without using reagent heating has been solved using the technique of a directed motion of drops, i.e., the method of heterogeneous hydrodynamic coagulation. The efficiency of water purification from microscopic oil drops, including those of the petroleum origin, is equal to 95–99% per one stage. The purification process lasts 10–30 min.

This study continues an earlier work devoted to simulation of mass transfer in liquid-liquid systems taking into account mass transfer across fractal interfacial structures. Earlier, using methods of nonequilibrium thermodynamics, we obtained an expression for the generalized thermodynamic force taking into account colloidal chemical phenomena in the interfacial region, such as the formation of disperse interfacial layers and films. Here, using a differential equation with a fractional-order derivative, we estimate the diffusion coefficient of the extractable substance in the interfacial film and the porosity of this film, which is its structural characteristic.

A mass transfer model in which the generalized thermodynamic force accounting for colloidal and chemical phenomena in the interfacial zone, such as the formation of disperse interfacial layers and films, is taken to be the driving force is considered. A method for calculating the difference between the pressures in the film and in the phase, the interfacial-film thicknesses, and mass transfer coefficients is proposed. It is found that the resistance to mass transfer in porous films varies with time, passing through a maximum.

The kinetics of heterogeneous hydrodynamic coagulation and coalescence of motor oil droplets 0.4–1.5 μm in size with a concentration of 0.15–0.5 vol % is investigated in a convoluted tube, a centrifugal pump, and their combination. Kinetic parameters of the coagulation-coalescence process, which proceeds hundreds times faster than sedimentation, are determined.

The mechanism of purification of an aqueous phase from droplets of Midel 7131 transformer oil with the use of heterogeneous hydrodynamic coagulation in the presence of a second organic solvent is considered. Models of heterogeneous hydrodynamic coagulation are proposed, and the simplest and most probable model variants are chosen.

A setup is designed to study the kinetics of heterogeneous hydrodynamic coagulation in the presence of a second organic solvent, which significantly accelerates the coagulation. Without coagulants, 5–20 min is sufficient to remove 80% of suspended transformer oil drops 2–10 μm in size. Addition of aluminum salts or ferrous salts to a concentration of 10−5–10−4 M increases the treatment rate by about an order of magnitude.

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.

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.

The kinetics of migration of monomolecular layers of surface-active extractants on water is studied. The problem is important in the context of radioactive contamination of the surface of water reservoirs and watercourses. The migration velocities of eight extractants used in the radiochemical industry and 37 systems containing these reagents are determined.

The migration velocities of surfactants on the surface of tap water are measured by the tracer method. The results are well reproducible, although the surfactants and the water are used without special purification. A decrease in the surfactant migration velocity with time was observed. It is found that the main cause of the decrease is an increase in the weight of the water adjacent to the surface film. The radial migration after a very short time is characterized by uniform surfactant motion.

The influence of surfactants and temperature on the intensity of interphase mass transfer in back extraction under conditions of forced Marangoni flows was studied.

Experimental evidence was obtained in favor of the existence of the fine structure of the interface region in the liquid-liquid system far from equilibrium. The predominant interface phenomenon in the liquid-liquid system proved to be the formation of dispersed layers, whose occurrence and evolution determine the mass and momentum transfer through the interface.

The hydrodynamics and kinetics of CO2 absorption by water when the interface is disturbed by partially immersed disks that execute torsional oscillations or uniform unidirectional motion (rotation) was studied. It is shown that interface disturbance and generated surface flows enhance mass transfer by a factor of 2.5 and lead to extremum dependences of the mass transfer coefficient on the area and thickness of the insoluble film covering the water surface. The surface flows generated by disks at the gas-liquid interface were examined. Two types of surface flows that differ by their direction and the nature of driving forces are revealed. The role of these flows in enhancing mass transfer at small Re numbers was elucidated.

Oil-in-water emulsions at concentrations of 0.001‐ 1 vol % are very important objects because they are involved in fine water treatment to remove oil microdrops and in the formation of cruds, which cause a nuclear hazard in radiochemical extraction processes. In this work, a method was proposed for studying the coalescence of microdrops of organic liquids on the surface of solids and cloths. It was shown that the determining step is a second-order process occurring on the collision of microdrops coming from the bulk with drops of surface clusters. Once the microdrop size has become smaller than a certain value, the process rate constant significantly decreases. It was found that the decisive role in the microdrop coalescence is played by the pH of the oil-in-water emulsion and the specific surface area of solids. The proposed mechanism accelerates the separation of oil drops from water by a factor of hundreds or thousands.

The principal interphase phenomena accompanying the transfer of a substance through liquid membranes (chemical reactions, the formation of supersaturation and microheterogeneity zones, spontaneous interphase convection), which are related to many important characteristics of the kinetics of ion transport, have been examined. By influencing these processes it is possible to control the rate of trans-boundary transfer. The bibliography contains 61 references.