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Vol. 6 Issue 3

Archives Journal Chemical Bulletin Vol. 6 Issue 3

Investigation of the features of sunflower oil emulsions and the effect of the emulsifier on the efficiency of sorption purification

 5-13 p.
Abstract
The emulsifying ability of surfactants is determined by the presence of hydrophobic and hydrophilic functional groups. The properties of the emulsifier affect the dispersed phase average size. Edible refined sunflower oil was used to prepare the emulsions. In the composition of oils, even after refining, small amounts of accompanying components are found after the plant tissues destruction. This allows the vegetable oil to be emulsified without surfactants addition. The article examined emulsions without the addition of surfactants and with sodium lauryl sulfate, as one of the most common components of detergents in the Russian Federation.
The purpose of the research was to study the colloidal chemical characteristics of vegetable oil emulsions in water and the influence of their properties on the efficiency of sorption purification. It has been shown that sodium lauryl sulfate in an amount of 0.05 mg/dm3 in the sunflower oil-water system leads to a decrease in the average diameter of oil droplets, as well as to a change in the ζ – potential of the oil micelle, from a weakly positive one it goes into a weakly negative region with an increase in charge as the emulsifier concentration increases. In the presence of an emulsifier, the efficiency of extraction of vegetable oils from aqueous media using the OSP600 sorp-tion material decreases.
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Analysis of physical and chemical processes of sulfur removal during agglomeration of ore raw materials

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 14-27 p.
Abstract
This paper analyzes the physical and chemical processes of sulfur removal during agglomeration of iron ore mineral raw materials to build a technologically efficient processing model. Thermodynamic aspects of the formation of sulfates are considered, taking into account the features of desulfurization of calcined ore materials in the presence of alkali-earth metal compounds in the charge of agglomerates, when sulfur dioxide is partially captured by them. It was found that the addition of limestone to concentrate and pure pyrite has no noticeable ef-fect on the removal of sulfur from the charge in the temperature range of 600-900 ° C during short-term firing due to the weak absorption of calcium carbonate by sulfur dioxide. Analysis of the agglomeration processes of sulfu-rous iron ore materials found that free lime absorbs sulfur well, since an intermediate stage is necessary for lime-stone absorption – dissociation of calcium carbonate. The factors contributing to decarbonization, which lead to a more complete removal of sulfide sulfur from oxidized iron ore materials, have been investigated. The thermody-namic analysis carried out by the authors allowed us to scientifically substantiate the experimentally observed in-tensification of the dissociation reaction of sulfates with an increase in temperature, a decrease in the partial pres-sure of oxygen in the furnace atmosphere during the processing of iron ore agglomerate. The data obtained in the study show that in oxidizing and slightly oxidizing conditions, sulfates decompose with increasing temperature if their contact with silicon and iron or aluminum oxides is ensured, and the formation of a melt accelerates mass exchange and promotes desulfurization. It is revealed that at the same time, liquid-phase sintering intensifies, in-hibiting the release of gases. In the conditions of the agglomeration process as a whole, the atmosphere is oxidiz-ing, although in some micro-volumes near the burning coke particles, the reducing potential of the gas phase is possible. Therefore, it makes sense to consider a uniform ratio between sulfate and sulfide sulfur in various gaseous environments.
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Overview of surfactant flooding as a method of increasing oil recovery and the applicability of microcapsulation technology to improve the efficiency of surfactant flooding

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 28-47 p.
Abstract
The problem of increasing the degree of oil recovery from reservoir formations has remained relevant over the past few decades.
Currently, there is a rapid increase in interest in chemical methods of increasing oil recovery to intensify oil production, in particular, flooding with surfactants (surfactants).
This article describes the factors affecting the efficiency of self-winding and the effect of adsorption on the eco-nomic component of the technology. To solve the problem of adsorption, preventing the large-scale introduction of surfactant, it is proposed to use the technology of microencapsulation of surfactants in a solid shell.
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Effect of nanostructure and surface morphology on Al2O3 coatings carried out during thermochemical treatment

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 48-64 p.
Abstract
The influence of thermochemical treatment of Al2O3 layers on their chemical composition, nanostructure, micromechanical and sclerometric properties, and surface morphology is presented. By anodizing in a three-component direct current electrolyte, oxide layers were obtained by means of an aluminum alloy EN AW-5251 (AlMg2). Thermochemical treatment was carried out directly in aqueous solutions of Na2SO4·10H2O and Na2Cr2O7·2H2O, as well as in water purified from mineral salts. A thermochemical treatment method is presented that transforms the surface structure of the layers (formation of a sublayer of Na2Cr2O7·2H2O and Na2SO4·10H2O) and significantly changes the thickness of the layers by 0.37 and 1.77 microns, respectively. It was revealed that thermochemical treatment in water led to the formation of a sublayer 0.63 microns thick. Micro-mechanical tests have shown an increase in the surface microhardness of layers in the case of their thermochemical treatment in water and Na2SO4·10H2O, as well as a decrease in layers modified in Na2Cr2O7·2H2O solution. The layer modified in Na2SO4·10H2O solution has the highest microhardness (7.1 GPa). Scratch tests indicate that thermochemically treated layers have better adhesive properties than the control layer. The optimal constancy with respect to scratches was demonstrated by the layer as a result of thermochemical treatment using a solution of 10H2O · Na2SO4 (the highest values for almost most critical loads), relates it to sliding contacts, which is provided with high load capacity and insignificant roughness.
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