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Vol. 8 Issue 1

Archives Journal Chemical Bulletin Vol. 8 Issue 1

Thermal decomposition of low-density polyethylene: kinetic study using TGA and DTG data

https://doi.org/10.58224/2619-0575-2025-8-1-1
Abstract
Pyrolysis of low-density polyethylene (LDPE) waste is considered as a highly efficient and promising recycling method. The aim of this work is to investigate the pyrolysis kinetics using three model-free methods (Friedman, Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS)) and two model-fitting methods (Arrhenius and Coates-Redfern). Thermogravimetric (TGA) and differential thermogravimetric (DTG) thermograms at 5, 10, 20 and 40 K min−1 showed a linear curve, which implies the first-order reactions. The kinetic parameter values (E_A and A) of LDPE were calculated at different conversions by three model-free methods, and the average values of activation energies obtained were in good agreement and ranged from 190.23 to 191.89 kJ/mol. These kinetic parameters were additionally calculated at different heating rates using the Arrhenius and Coates-Redfern methods.
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The Review of corrosion protection by nanotubes TiO2 and BTA/TiO2 nanotubes dispersed in Epoxy and proposed method for preparation of anti-corrosion coating from this material assisted by ultrasound

https://doi.org/10.58224/2619-0575-2025-8-1-2
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Abstract
This review presents the corrosion resistance of epoxy coatings containing TiO2 nanotubes and BTA (benzotriazole)-modified TiO2 nanotubes. The purpose of the study is to examine how effectively these materials protect against corrosion on metal surfaces in various environments. The synthesis of TiO2 nanotubes and BTA/TiO2 nanotubes in epoxy coatings offers a promising approach to significantly enhance corrosion resistance while also opening considerable potential for applications in industries requiring high durability and material protection.
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The effect of the complexing components of the washing system on the hydrophilizing properties of the composition

https://doi.org/10.58224/2619-0575-2025-8-1-3
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Abstract
The development of effective and effective formulations of detergents has been an urgent task for a long period. The washing composition includes a large number of various raw materials components that perform certain functions. Today, the market of chemical raw materials has a wide range, which makes it possible to select the necessary components, depending on the required properties and characteristics of the products. Surfactants, which no composition can do without, as well as complexing additives, which not only serve to bind hardness ions during the cleaning process, but also enhance the washing ability of the entire system, are important and mandatory elements of the washing system. Currently, the most popular chelating agents are sodium tripolyphosphate, eth-ylenediaminetetraacetic acid, hydroxyethylenediphosphonic acid, etc. However, based on recent scientific research, it can be concluded that trip. Taking into account this information, such complexes as oxy-ethylene diphosphonic and ethylenediaminetetraacetic acids are beginning to gain great popularity, since they have the necessary set of properties and characteristics for use in detergent formulations, are affordable and simple in the process of technological application. The article describes the influence of the nature of the complexing components that make up detergents on enhancing the cleansing effect and increasing the effectiveness of compositions. For this study, the sedimentation volume method was chosen, which made it possible to evaluate the hydrophilizing effect on the carbon surface in systems with various types of complexing agents. Based on the results obtained, conclusions were drawn about the most effective and suitable chelating agent for this washing system, and the most optimal concentration of the complexing agent was selected.
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Atomic refraction by oxygen as a method for assessing the activity of oxygenates for internal combustion engines

https://doi.org/10.58224/2619-0575-2025-8-1-4
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Abstract
Relevance: it is proposed to evaluate the efficiency or activity of oxygenate compounds by the value of oxygen atomic refraction. This will allow developing new components and additives for the production of motor fuels based on available domestic raw materials.
Objective. Comparison of the efficiency of oxygenate additives and supplements using simple calculation meth-ods.
Methods: a calculation method for determining the molecular and atomic diffraction of oxygenates was used.
Results and conclusions: all oxygenate compounds contain oxygen and the lower the atomic refraction, the more active the vibrations of atoms and electrons in the molecules of oxygenate compounds. Thus, the lower the atomic refraction of oxygen, the higher the activity of the oxygenate. Both molecular and atomic refractions of the main oxygenates have been determined, which made it possible to compare the oxygenates in use and those with potential. An important point is the specific refraction per 1 gram of substance. It is also possible to compare the activity of oxygenates, but in the reverse order: the higher the specific refraction, the more effective the compound is for a spark-ignition engine. For diesel engines, it is desirable to have higher atomic refraction and lower specific refraction per 1 gram of substance, i.e. in the reverse order.
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