The paper provides information about phosphogypsum waste from various enterprises and how it can be used in the production of slow-release fertilizer mixtures. Such fertilizer mixes can potentially be used with different types of soil, including acidified soils. Experiments were conducted on phosphogypsum samples from the old and new dumpsites under the Taraz branch of Kazphosphate LLP. All representative samples underwent chemical, mineralogical, thermal gravimetric and differential thermal analyses, as well as Fourier-Transform Infrared (FTIR) spectroscopy and polarized optical microscopy (POM). No significant differences were found in the content of the samples. Phosphogypsum from the old dumpsite contained 87.93% gypsum (CaSO 4 • 2H 2 O), 9.10% quartz (SiO2), 17.55% calcium (Ca), 0.13% potassium (K), 0.35% phosphorus (P), and 0.80% phosphorus pentoxide (P2O5). Phosphogypsum from the new dumpsite contained 85.04% gypsum, 10.58% quartz (SiO2), 19.42% calcium (Ca), 0.14% potassium (K), 0.30% phosphorus (P), and 0.69% phosphorus pentoxide (P2O5). The current paper also offers a technological scheme for making a slow-release fertilizer mixture with phosphogypsum.

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This paper presents a technology for applying copper and silver films to cotton fabrics by combining photochemical and chemical methods for the reduction of the compounds of these metals. The resulting metal-containing films have inherent electrical conductivity of metals. All the main processes described in the work were carried out by means of the compounds being sorbed by the surface of the fabric when they were wetted in appropriate solutions. The aim of the work was to study the application of electrically conductive composite copper films on cotton fabrics. The tasks to achieve this aim were to perform scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction analysis to confirm that as a result of the experiment, CuCl with a semiconductor ability was formed on the surface of the sample. The driving force behind the photochemical reduction of copper and silver halides on cotton surfaces is that, as a result of the photooxidation of cellulose molecules in the fabric, copper monochloride is first formed on the cotton surface. Subsequently, the process of obtaining silver particles based on semiconductor silver chloride obtained as a result of the transformation of copper monochloride was carried out. The physicochemical and photochemical processes leading to the formation of monovalent copper chloride, which provides sufficient adhesion to the substrate, are considered. It is shown that in this case, the oxidation of monovalent copper also occurs with the formation of soluble salts that are easily removed by washing. Since the proposed technology does not require special equipment, and the chemical reagents used are not scarce, it can be used to apply bactericidal silver films to various household items and medical applications in ordinary laundries or at home. This article examines an affordable and simple technology for producing metal films on a cotton surface due to the presence of disadvantages (time duration, high temperature, scarce reagents, special installations, etc.) of a number of well-known methods in the production of chemical coatings.

Recovery of fat-and-oil production wastes will reduce the technogenic impact on the environment, as well as involve them in a new production cycle as a secondary material resource. As part of solving this problem, the possibilities of using fat-and-oil production wastes in the production of a tyre reclaim and a modified tyre reclaim are considered. In the course of the studies, the fat-and-oil industry wastes’ sorption characteristics are determined, and in relation to oils in static and dynamic conditions, the spent reagent reclamation ways are determined. The authors obtained a tyre reclaim and a modified tyre reclaim using the fat-and-oil industry wastes (soap stock, diatomite, bleaching clay, and fatty acids isolated from soap stock). In this work, the authors studied the possibility of using the fat-and-oil industry wastes in the formulations of a tyre reclaim and a modified tyre reclaim. Extended physical and mechanical tests of experimental rubbers led to the conclusion that it is most expedient to use the fat-and-oil industry wastes in the formulation of rubber compounds for production of sleeper pads for railroad tracks, since when using a tyre reclaim and a modified tyre reclaim, the indicators of rubber properties practically do not change and comply with control standards.