Mankind has been aware of zeolites since 1756, when the Swede, Axel Fredrik Cronstedt (1722–1765), observed the strange behavior of a certain natural mineral (probably stellerite with some amounts of stilbite) [...]
In this paper, the system of natural mineral alkali fluxes used in typical mineral industry technologies was analyzed. The main objective was to lower the melting temperature of the flux systems. The research has shown that the best melting parameters in the Ca–Mg– (Li,Na,K) system were characterized by the composition: A-eutectic 20% and wollastonite 80%, and it was reached at temperature 1140 °C; in addition, this set had the widest melting interval. Selected thermal parameters of mineral flux systems were also calculated. The technological properties of mineral composites such as shrinkage and brightness were also analyzed.
Prioritized drinking water contaminants found in water supply systems of the Russian Far East and their possible unfavorable influence on the population health have been reviewed. It is shown that drinking water natural mineral composition peculiarities have to be borne in mind when the level of somatic morbidity of the population is determined, which is essential due to intensified economic advancement of the region.
Abstract
The possibilities of recreational-oriented use of the coast are studied on the basis of the trend analysis in the development of the coasts and regional features of the exploitation of the coasts of Sakhalin Island and the Crimean Peninsula. It is shown that the loss of recreational capacity of coastal territories is the result of both man-made and natural components of development. The conclusion is made about the degradation of a significant part of the recreational resources of the coasts. The concept of a model of integrated use and sustainable development of natural mineral resources, hydrogeological and recreational resources is proposed.
Abstract
Degradation of organic pollutants by heterogeneous Fenton-based advanced oxidation processes has been proved to be an efficient method. The use of naturally occurring catalysts as H2O2 activators is of particular interest in environmental remediation. This work applied a low-cost and eco-friendly natural mineral under UV-light irradiation to degrade organic dye in water. To study the performance of the natural mineral in photo-Fenton oxidation, methylene blue (MB) was employed as a model dye pollutant. The morphology and chemical composition of the natural mineral were characterized using various techniques. The effects of different experimental conditions such as the initial pH of the solution, the amount of catalyst, and initial dye concentrations on the degradation efficiency were investigated. The degradation of methylene blue reached 91.3% at optimum reaction conditions; 0.1g catalyst and 100 mg L‒1 H2O2 concentrations for 10 mg L‒1 initial dye concentration after 180 min of treatment. The pseudo-first-order kinetic model exhibited a better correlation coefficient (R2 > 0.98) in explaining the degradation kinetics of MB. The applied natural mineral showed good catalytic activity and will open a door towards large-scale wastewater purification from dyes. Furthermore, the plausible mechanism of the heterogeneous photo-Fenton oxidation is discussed.
Catalysis in Zeolites and Zeotypes—Cornerstone of Chemical Industry and Permanent Subject of Research
