Chemical Safety Science

Current issues of the efficacy and safety of quaternary ammonium compounds when used in antiseptic and disinfectant agents ‒ a review

Vadim M. Vasilkevich — 2025-06-23

The publication summarizes and analyzes current data from various literary sources on the issue of the effectiveness and safety of using quaternary ammonium compounds in biocidal agents. Using ionic liquids and quaternary phosphonium compounds as examples, important aspects of the development and synthesis of new antimicrobial compositions as alternative chemical agents with high target efficiency and a lower degree of potential toxicity are discussed. The information presented in the article indicates the need to reconsider the practice of widespread use of QACs in biocidal products, closer attention from regulatory authorities during testing and registration of new disinfectants and antiseptics based on QACs, and the importance of additional targeted research for an objective assessment of the problem.

Toxicological evaluation with determination of hazard classes of laureth-4-phosphate-based adjuvant using experimental and computational methods

Svetlana Yu. Petrova — 2025-06-23

A preparation based on ethoxylated alcohol, widely used in agricultural production as an adjuvant (surfactant) together with pesticides of chemical synthesis, was chosen as an object of study of toxicity parameters. The paper presents original data of toxicological studies, carried out by experimental and calculated method, to determine the hazardous properties of adjuvant based on laureth-4-phosphate, used in the agricultural sector of the country together with pesticides of chemical synthesis. Also the paper reflects information on the classification of hazards of the studied chemical products for human health, obtained as a result of application of two different methods - calculated and experimental, for assessment by parameters of acute intragastric toxicity and acute toxicity when applied to the skin, assessment by parameters of allergy hazard.

One of the main criteria in selecting an approach for toxicological studies of chemical products is the completeness of available data on the hazardous properties of its components (toxicological profile). the use of a combined approach in complex toxicological studies of chemical products (using experimental and computational methods of establishing hazard classes) not only allows to obtain the most complete and comprehensive assessment of preparations in terms of hazardous properties for human health, but also provides a harmonious and comprehensive assessment of their properties.

Sorption treatment of phenol-containing wastewater with silicon and carbon-containing materials

Sergey V. Dovgan — 2025-06-23

The paper was studied phenol sorption from aqueous solutions by silicon- and carbon-containing materials obtained from rice husk and straw under different conditions.. It is shown that the phenol sorption activity for samples obtained by pyrolysis of rice husk under industrial conditions was 39%. Silicon- and carbon-containing materials synthesized by oxidative roasting under laboratory conditions do not absorb phenol. The pyrolysis products have a complex structure and are in an amorphous and amorphous-crystalline state. Kinetic studies have shown that phenol sorption is limited by two stages: on the one hand, by internal and external diffusion, and on the other hand, by chemical interaction with surface active groups of samples. Thermodynamic parameters indicate that the process is spontaneous (ΔG298 < 0) and exothermic (ΔH < 0), the mobility of the phenol molecule decreases during adsorption (ΔS < 0). Processing of phenol adsorption isotherms using Freundlich, Dubinin-Astakhov, Langmuir and BET models showed that sorption is determined by non-covalent adsorbate-adsorbent interactions. It was found that with increasing pH, the absorption capacity decreases, which is due to the form of phenol (as a molecule or phenolate ion). The low degree of phenol desorption by distilled water and sodium hydroxide solution confirms the strong interaction of phenol with the surface of materials, which depends on the contact time and the solution environment.

Research of the sorption properties of a sorbent based on nano-sized carbon in relation to La(III) ions and optimization of the conditions for its sorption using mathematical modeling

Rimma R. Ilyasova — 2025-06-23

This research describes the sorption of lanthanum(III) ions by nanosized carbon particles with a particle size of 10 - 100 nm with a maximum of 30 nm. The sorption properties of nano-sized carbon in relation to lanthanum (III) ions were researched. It has been established that the sorption of lanthanum(III) ions by nanosized carbon particles is described by the Langmuir model. Optimization of sorption conditions made it possible to achieve a high sorption activity of nanocarbon towards lanthanum(III) ions of 87 %. A high sorption efficiency of nano-sized carbon was revealed in comparison with literature data. A mathematical model of the sorption process, calculated using OpenFOAM software, is presented, with the maximum concentration of lanthanum(III) ions observed on the surface of the sorbent.

Utilization of Brines Using Liquid Glass

Victor V. Mironov — 2025-06-23

Highly concentrated salt solutions (brines) formed during mining, seawater desalination and industrial processes pose a serious environmental problem. Traditional disposal methods, such as discharge into water bodies or injection into underground formations, are expensive and environmentally unsafe. In this regard, the search for alternative methods of processing brines to obtain useful products is becoming relevant. The paper examines the possibility of utilizing brines using liquid glass (sodium and potassium silicates) and studying the properties of the resulting reaction products. Liquid glass solutions with different moduli were used for the experiments. The brine was passed through a layer of liquid glass, which led to the formation of gel-like flakes. The solid phase was separated from the liquid, after which its composition was analyzed using X-ray diffraction analysis (XRD), X-ray phase analysis and electron microscopy. The processes of hydrolysis, polymerization and formation of porous structures were also studied. It has been established that the interaction of liquid glass with brines results in the formation of poorly soluble silicate materials with a developed porous structure. These materials demonstrate high adsorption capacity with respect to NaCl ions and other impurities. It has been shown that the properties of the resulting products depend on the type of silicate (sodium or potassium), its concentration and reaction conditions. The resulting solid phases can be used in the construction industry. The study confirms the scientific novelty of the proposed method for the utilization of brines, which allows not only to reduce the environmental load, but also to obtain useful materials. The results of the work open up prospects for the practical application of silicate products formed as a result of brine treatment with liquid glass in industry.

Modernization of chemical cleaning of waste from the production of varnish collodions

Alexander V. Supyrev — 2025-06-23

A study was conducted of the process of chemical purification of waste from the production of varnish collodions, namely, the so-called trap collodion (TCL). It was found that the maximum effect of removing iron compounds and hardness salts sorbed by TCL fiber is achieved with the combined presence of nitric and phosphoric acids in the cooking solution. Based on the conducted studies, a process for cleaning nitrate cellulose return waste was developed. It was shown that the cost of collodion made from TCL, depending on the degree of TCL contamination, is 20-40% lower than the cost of collodion obtained by processing cellulose.

Prospects for the application of microwave radiation for the pyrolysis of various plastic waste type

Natalia Yu. Kovaleva — 2025-06-23

The use of microwave radiation for pyrolysis is one of the most promising technologies for recycling plastic waste and biomass into valuable organic products. In the review microwave pyrolysis as an alternative to traditional pyrolysis due to its advantage in providing fast and efficient heating has been discussed in detail. In this article, the key parameters affecting the yield and composition of pyrolysis products: a type of plastic and absorbent, temperature, microwave power, residence time and catalysts have been reviewed also. The main problems and limitations of this process have been discussed. Examples of energy balance assessment and technical and economic analysis of the microwave pyrolysis process are given. The possibilities of using microwave pyrolysis on an industrial scale have been analyzed.

Trends in innovative solutions to reduce risks hydrogen transportation using – а review

Rugiya A. Ismayilova — 2025-06-23

Today, hydrogen obtained from renewable resources is not only a promising energy source that reduces dependence on fossil fuels, but also an important factor in the fight against global warming, reducing harmful emissions into the atmosphere. The success of large-scale use of hydrogen depends on its delivery to consumers, the priority type of which is pipeline transport. The proposed article is an analytical review of innovative solutions aimed at ensuring the safety of hydrogen transportation by pipeline. The mechanism of hydrogen embrittlement of metals is given, which is a key factor, deteriorating their mechanical properties, leading to hydrogen leakage in steel pipelines. The created technical solutions capable of ensuring safe transportation of hydrogen are considered, including new functional materials for the production of steel and polymer pipelines. The possibility of transporting hydrogen together with natural gas using both steel and polymer pipelines is shown. Attention is paid to the issue of monitoring leakage and accumulation of hydrogen during operation of the main pipeline.

La(III), Cu(II) and their combinations effect on the unicellular alga Scenedesmus quadricauda (Turp.) Breb

Maria A. Sysolyatina — 2025-06-23

Metals enter the environment together. The aim of the work was to evaluate the effect of La(III), Cu(II) and their combination (1:1) on the unicellular alga Scenedesmus quadricauda (Turp.) Breb at low concentrations of metals in the aquatic environment. CuSO₄·5H₂O and La₂(SO₄)₃·8H₂O salts were added to drinking water to achieve concentrations of 0.000008‒0.0016 mmol/l calculated per metal ion or their sum (1:1). Biotesting was carried out using the method of accounting for the number of algae cells after 72 hours of exposure. The effect of Cu(II) had a slight stimulating effect: the number of cells increased maximally in solutions with 0.0008 and 0.0016 mmol/l of metal (1.2‒1.3 relative to control). La(III) significantly stimulated increasing amount of algae cells (4.2‒11.1 times) for the entire range of tested concentrations. With the combined effect of Cu(II) and La(III), the hormesis was of medium intensity compared to the effects of the metals separately (1.8‒2.9 times of the control). Thus, it was shown for the first time that vital concentrations of Cu(II), La(III) and their combinations in the aquatic environment lead to an increase in the reproduction of green algae. The effects of La(III) exceed the essential effect of Cu(II). Consequently, even a minor influx of metals into aquatic ecosystems can lead to their eutrophication.

Dependence of megacity aerosol pollution estimates based on the atmospheric electric field strength on the unperturbed conductivity profile

Alexey V. Krasheninnikov — 2025-06-23

Ultrafine particles are very harmful to human health, so it is extremely important to develop indirect methods for estimating the concentration of aerosol particles with sizes up to 0.1 µm in diameter in atmosphere. Aerosol particles and the atmospheric electric field strength are tightly related with each other what allows the electric field usage for such estimates. The impossibility of in situ measurements of altitude dependencies, especially for the conductivity function, necessitates a study on the dependence of the results obtained on the specific profile taken. In this study, numerical estimates of the parameters of the model for estimating aerosol concentration in the air on the basis of electric field strength values for three conductivity profiles proposed from literature sources are used: a profile consisting of a single exponent, a profile consisting of three exponents, and a profile that well reflects the characteristics affecting the electric field of the surface layer atmosphere. It is shown that the use of two close profiles reflecting the altitudinal inhomogeneity of the conductivity profile gives almost indistinguishable results, however, a very different profile strongly changes the obtained estimates (the particle concentration in a megacity changes by almost an order of magnitude).

Peculiarities of calculation of individual risk taking into account seasonal factor

Vladislav S. Gasilov — 2025-06-23

Seasonal fluctuations and factors have a significant impact on various spheres of activity of a modern enterprise. Understanding these factors allows for a more accurate assessment of production risks and making informed decisions. Seasonal factors in Russia, given its size and diversity of climatic zones, have a significant impact on the operations of hazardous production facilities (hereinafter - HPF), and in the context of global climate change and economic instability, they are becoming increasingly significant in the operation of HPF. In this regard, a more flexible adaptive approach to risk assessment is required, which creates a need for research and implementation of new calculation methodologies. In recent years there has been a growing interest in integrating the seasonal factor into risk management. This creates an opportunity for further research and exchange of experience, so the study of the peculiarities of calculating individual risk taking into account the seasonal factor is relevant for both theoretical understanding and practical application in various industries. The article discusses the key aspects and methodological approaches to the calculation of individual risk taking into account seasonal temperature fluctuations. The authors analyse existing approaches to calculate individual (potential-territorial) risk and note that these methods are valid for technological processes, which are carried out at temperatures above the maximum air temperature in the corresponding climatic zone, and for industries, the technological process of which is carried out at ambient temperature, such an approach gives highly overestimated results, which leads to unnecessary material costs in the design and new construction of GRO. Therefore, it is proposed to calculate the individual (potential-territorial) risk taking into account the seasonal factor for production facilities, the technological process of which is carried out at ambient temperature. Such integration of the seasonal factor impact analysis into the risk management system will increase the efficiency of decision-making and allow more accurate forecasting of potential threats.

Monitoring of new binary systems for caffeine extraction from natural raw materials

Alexander S. Melnikov — 2025-06-23

The article summarizes the results of monitoring new binary systems for caffeine extraction (dispersion method) from natural raw materials using Camellia sinesis L. leaves and Coffea arabica L. beans as an example. Tea (Camellia sinesis L.) in the Russian Federation is grown in the Krasnodar region, so modification of methods of caffeine maceration from this raw material will certainly increase the potential of Russian production of this alkaloid. In turn, such methods, as more environmentally friendly, will eventually be able to replace the existing methods of condensation of cyanide-containing reagents and amides with urea (Traube method). Binary combinations of "ethyl acetate/aliphatic alcohol" in various ratios were used as the organic phase of the new, more economically advantageous systems, and the classical chloroform extraction method was chosen as the comparison method. In this research, the aliphatic acyclic saturated alcohols in different structural forms were analyzed as the second component of the organic phase of the extraction system. As a result, it has been proven that new extraction systems allow for a more complete extraction of caffeine from natural components. Modification of the extraction process will produce pure and environmentally friendly caffeine from natural raw materials, and will provide an economically suitable caffeine production process for the domestic producer.