сорбція

INVESTIGATION OF SORPTION / DESORPTION PROCESSES OF MEDICAL SUBSTANCES BY COMBINED HYDROGELS

Modern hydrogel healing therapies for damaged human skin, must perform a number of functions which are inherent for the skin: 1) preservation of thermal and water balance; 2) ensuring of oxygen penetration; 3) providing transportation of substances necessary for the functioning of the organism; 4) protection from mechanical damage. When using hydrogel coatings on damaged areas of the skin, they must perform, an additional function - prolonged delivery to the wound of therapeutic agents of various nature.

Removal of Petroleum from Aqueous Systems by Poly(divinylbenzene) and Poly(methyl methacrylate-divinylbenzene) Resins: Isothermal and Kinetic Studies

In this study, the performance of two polymer resins was evaluated, one composed of methyl methacrylate-divinylbenzene (MMA-DVB) and the other of only divinylbenzene (DVB), for adsorption of oil in synthetic oily wastewater. The tests were carried out using two processes: (i) continuous flow, to assess the quantity of oily water that can be eluted until reaching the saturation point of resins; and (ii) batch, to obtain information about the best-fitting kinetic and isotherm models for the two resins.

Improvement of Adsorption-Ion-Exchange Processes for Waste and Mine Water Purification

The increase of ecological safety level of the hydrosphere as a result of the improvement of the adsorption processes for waste and mine water purification by using natural sorbents and desalting processes via electrodialysis has been investigated. The optimal parameters of improved sorption processes with natural sorbents have been established. The mechanism of diffusion was studied by the “kinetic memory” method. Effective coefficients of pore diffusion were determined during sorption of pollutants by natural sorbents.

Removal of Methylene Blue by Adsorption onto Activated Carbons Produced from Agricultural Wastes by Microwave Induced KOH Activation

The present study aims to describe new low cost activated carbons which were prepared from bean peel (BP), acorn peel (AP) and Pistacia lentiscus (PL) under microwave induced KOH chemical activation for the removal of methylene blue dye from aqueous solutions. Activated carbons were characterized using, thermogravimetric analysis, and scanning electron microscopy. The adsorption properties were examined considering several parameters including the effect of pH, contact time, adsorbent dosage and initial concentration.

Statics and Kinetics of Albumin Adsorption by Natural Zeolite

The statics and kinetics of albumin adsorption on natural zeolite of clinoptilolite structure have been investigated. The basic characteristics of zeolite have been determined. The method of albumin in a solution analysis was given. An isotherm of albumin adsorption was plotted and the Langmuir equation describing this isotherm was given. The presence of an external and pore diffusion adsorption mechanism has been experimentally established during the study of kinetics in a machine with mechanical stirring.

Aqueous Extracts of Opuntia Ficus-Indica as Green Corrosion Inhibitor of A283C Carbon Steel in 1N Sulfuric Acid Solution

The effect of concentration and temperature were studied to measure the inhibiting capacity of extract Opuntia ficus-indica by using polarization and electrochemical impedance spectroscopy. The adsorption of the studied extract on carbon steel surface obeys the Langmuir adsorption isotherm.

Lead Adsorption by Nano-Hydroxyapatite Granules in a Fixed-Bed Column

The sorption of Pb2+ ions was conducted in a fixed-bed column by using nano-hydroxyapatite granules. The breakthrough and exhaustion time decreased with increasing flow rate, decreasing bed depth and increasing influent lead concentration. The proposed mechanism is a partial dissolution of calcium followed by the precipitation of an apatite by the ion-exchange mechanism with the formula Ca10−xPbx(PO4)6(OH)2 and Pb10(PO4)6(OH)2.

Adsorption of Cadmium Ions from Aqueous Solutions on Modified Sorbents

Some new modified sorbents based on opoka from Astrakhan region were obtained. A comparative study of the sorption of cadmium ions on the surfaces of the sorbents was made. Also the static adsorption isotherm of substances from aqueous solutions was studied. The change of enthalpy, isobaric-isothermal potential and entropy of sorption and kinetics of cadmium ions sorption from water solutions were calculated. The results of the study can be used for the water purification from cadmium ions

Thermodynamics of (NH4+) Cation Adsorption Under Static Conditions

The adsorption of ammonium ions by natural zeolite and Al2O3 under static conditions has been investigated. The reason for changing the investigated solution pH during adsorption of ammonium ions on Al2O3 has been grounded. A phase diagram of the twocomponent system has been constructed and the composition of the adsorption system in the state of equilibrium has been determined. The thermodynamic calculations of the adsorption system Al2O3–NH4Cl–H2O have been carried out.

Surface characteristics of materials based on sodium liquid glass modified by polyvinyl alcohol and polyvinylpyrrolidone

The physicochemical properties of surface of the metal-containing polymer-silicate composites, which have been obtained due to compatible precipitation of water-soluble polymers and silicates under the influence of metal chlorides, such as specific surface area, the number of active centers, moisture absorption, sorption ability were studied.