zeolite

The process of modification of natural clinoptilolite, pre-enriched by the main component, with manganese ions from nitrate solutions as precursors for obtaining manganese(IV) oxide was studied. The value of the sorption capacity of different fractions of clinoptilolite with respect to manganese ions at room temperature was determined, and the sorption rate and rate constants of this process were calculated. The influence of the concentration of manganese nitrate solution on the sorption capacity of certain fractions of zeolite was determined.

The article is dedicated to the problem of decarbonising industrial gas emissions using adsorption methods. The article examines promising approaches to reducing carbon dioxide (CO₂) emissions using adsorption materials with high selectivity and efficiency in capture processes. The purpose of the study is to determine the adsorption capacity of various types of adsorbents, including synthetic and natural materials, in particular, fly ash synthesised by the hydrothermal method, zeolite obtained by the sintering method, natural zeolite, and fly ash from thermal power plants.

The influence of dispersion on the structural and sorption properties of the Transcarpathian clinoptilolite of the Sokyrnytske deposit was investigated by the method of complex thermal analysis. For a sample with a grain size of 0.14 mm, the effect of heat treatment on the ability to sorb water vapor was investigated. Thermal activation of clinoptilolite was carried out at temperatures of 200°C, 300°C, 400°C.The sorption capacity of natural and thermally activated clinoptilolite samples with relative to water vapor was investigated by thermal analysis.

In detail, this study analysed the kinetics of ammonium ion adsorption under dynamic conditions in the "clinoptilolite -ammonium ion" system. The work includes constructing a mathematical model of this process, which allows us to estimate and predict its essential characteristics. Calculations of mass transfer coefficients revealed their dependence on the intensity of medium mixing. A significant result is that ion exchange occurs in externally diffusion and intradiffusion regions.

The paper presents the results of the study of the statics of adsorption of surface-active substances from model solutions by activated carbon and zeolite. The results of photometric determination of the concentration of anionic surfactants before and after adsorption are presented. The results of adsorption capacity calculations are presented. The experimental results using the program (Langmuir 1.03) were numerically calculated. Sorption isotherms of sodium dodecyl sulfate indicate the mechanism of monomolecular physical adsorption.

The article is devoted to the study of the prospects of using compost with sewage sludge in the raw material for the recultivation of disturbed lands. A special installation was used for bio-composting, which allowed controlling of the process parameters. The results of bio-indication of composts obtained under different conditions of compositions of the raw material mixture are given. Based on the analysis of the results of bio-indication, the optimal composition of the raw material mixture using "fresh" and "old" sewage sludge is established.

Batch experiments are applied to determine the effectiveness of zeolite addition on the characteristics of wastewater of the oil industry and operational factors. The concentrations of heavy metals were measured using an atomic absorption spectrophotometry. Results have shown that 2.5 g/L of zeolite at a speed of 270 rpm, 6.5 pH would result in about 99% removal efficiency.

The kinetics of adsorption of ammonium ions under dynamic conditions has been studied. A mathematical model of the process was built. The mass transfer coefficient was calculated depending on the intensity of the change of location. It was established that ion exchange occurs in external and internal diffusion regions. The rate constants of ion exchange for the region of external and internal diffusion were calculated.

This work reveals a method of complex thermal and chemical activation of natural clinoptilolite from Sokyrnytsky deposit. The chemical activation of a mineral was carried out by HCl solutions treatment at various ratios of liquid-to-solid phases. With the use of thermal and infrared (IR) spectroscopic analyses, the adsorption property of a natural and activated clinoptilolite has been examined for water vapor. The ability of complexly activated clinoptilolite to adsorb direct dyes from their aqua solutions has been investigated.