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Vol. 4 Issue 2

Archives Journal Chemical Bulletin Vol. 4 Issue 2

PROSPECTS FOR THE USE OF SOSNOVSKY HOGWEED PROCESSING PRODUCTS IN CHEMICAL TECHNOLOGY

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 7-16 p.
Abstract
It is shown that restrictions on the spread of the invasive and dangerous for humans plant of Sosnovsky hogweed are carried out as needed. One of the restrictions on the spread of this plant can be the processing of Sosnovsky hogweed using chemical technology. It was determined that the optimal conditions from the standpoint of chemical technology are the processing of the fruits of this plant of waxy ripeness. Extraction processing of the fruits of wax ripeness with petroleum ether in a Soxhlet apparatus made it possible to obtain 2.9% of the mass. essential oil, which, according to chromatographic analysis using a gas chromatograph equipped with a flame ionization detector, an electronic integrator Crystallux 4000M, contained 56% of the mass. esters. The work shows that the essential oil in the composition of the compound with vaseline oil in a ratio of 1: 1 by volume can be used not only as a softener in the formulation of rubber compounds based on light crepe, but also as a plasticizer, imparting increased frost resistance to technical rubbers. With practically the same elastic strength characteristics of rubbers under tension with industrial oil I-12A and with essential oil, the increased frost resistance of rubbers with essential oil will allow them to be utilized into crumb rubber for the production of polymer-bitumen binders that reduce cracking of road surfaces.
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STUDY OF AGGREGATIVE STABILITY OF LIPID CONCENTRATE PRODUCTION MODEL WASTE WATER AND POSSIBILITY OF ITS PURIFICATION BY SORPTION METHOD

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 17-28 p.
Abstract
In the Belgorod region, work is underway to create the first high-tech large-scale production of lipid concentrate and animal protein from the larvae of the Black Soldier fly Hermetia illucens in Russia. The lipid concentrate emulsifies well in tap water, which indicates the presence of substances in it that do not belong to triglycerides of fatty acids. Obviously, it contains impurities of compounds present in the larval biomass - protein compounds and their decay products, phospholipids, etc., which can play the role of surfactants. This paper presents the results of studies on the possibility of fat-containing wastewater purification using a sorption material obtained by leaf litter of the horse chestnut genus (Aésculus hippocastanum L.) carbonization. It was found that the lipid concentrate is easily emulsified, both in pure form and in the presence of sodium lauryl sulfate. The resulting emulsions are highly resistant to degradation. It was found that the presence of the surfactant in an amount of 0.01 g/l improves the purification efficiency in the process of the model emulsion adsorption treatment. The addition of 0.6 g of the material allows to reach 92% purification, and with the addition of 1.5 g the efficiency is 98%. Similar amounts of sorbent in a pure emulsion make it possible to achieve values of only 35% and 88%, respectively. When finely dispersed particles of inorganic substances are added to an aqueous medium, the suspension effect is often observed, which manifests itself in the difference between the pH values of the suspension and the filtrate. The results of studies of the amount of added sorbent effect on pH changes in suspensions and filtrates showed that the complex «lipid micelle + sorbent» has a positive charge, and in the presence of the surfactant the charge retains a positive value, but is very close to neutral. An approach to the isoelectric point is observed.
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PALLADIUM NANOELECTROCATALYSTS ON COMBINED MATRIX-SUPPORTS FOR CHEMICAL POWER SOURCES

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 29-36 p.
Abstract
Fuel cells with direct oxidation of formic acid are promising converters of chemical reaction energy into electricity due to the high open-circuit potential, safe (non-flammable and non-toxic) fuel and higher energy characteristics compared to chemical current sources with direct oxidation of alcohols. The crossover effect with a low formic acid content allows the thin membrane application, as well as a high concentration of fuel (up to 20 M), which helps to increase the structure specific power parameters as a whole. Catalysts based on Pt or Pd are widely used in the electrooxidation reaction of formic acid. It has been known that catalysts based Pd are more effective than that Pt due to their resistance to carbon monoxide as the main reaction product. In this paper, the volt-ampere and watt-ampere characteristics of formic acid-based fuel cells and air under model operating conditions were studied. The tests were carried out on a certified laboratory stand of a fuel cell, to which a working model of the investigated membrane-electrode unit was connected. The optimal characteristics of the catalyst loading are established to achieve optimal parameters of current density and specific power. The creation of new catalysts and the modification of existing ones will help to increase the electrodes operation time, reduce the production cost, in-crease their efficiency by increasing efficiency, and also use as fuel not only hydrogen, but also other fuels such as formic acid.
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MODELING OF COMPLEX OF DENDRIMER WITH PEPTIDE

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 37-47 p.
Abstract
Biocompatible branched polymers can be used in many biomedical applications, including drug and gene delivery. In previous articles, we applied a computational approach to study complexes of positively charged lysine branched polymers and their complexes with some negatively charged regulatory oligopeptides. The goal of this article is to test the possibility of complex formation between peptide dendrimer and therapeutic oligopeptide molecules. A system consisting of one dendrimer, 16 oligopeptide molecules and counterions in water was studied by the molecular dynamics method. For this purpose, the Gromacs molecular modeling software package and the Amber force field were used. First of all, the process of complexation was studied and it was shown that negatively charged oligopeptide molecules are attracted by the dendrimer and quickly form a stable complex with it. After reaching a plateau of all characteristics of the complex, its average equilibrium dimensions, shape anisotropy, and internal structure were calculated. They turned out to be similar to the characteristics of the complexes formed by other branched lysine molecules with similar molecular weights and charges.
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SORPTION PROPERTIES OF BLACK SOLDIER FLY (HERMETIA ILLUCENS) MAGGOTS VERMICULTURING ZOOCOMPOST TO «METHYL ORANGE» DYE

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 48-57 p.
Abstract
The paper considers the issues, concerned with possible release as part of sewage waters of an organo-mineral pollutant ‒ methyl orange dye – to the environment. This dye has become widely used in textile industry, food industry, and in building materials production. High concentrations of this dyestuff are toxic and can cause damage to skin and eyes. Getting into the body system, the dye can form even more toxic aromatic amines in course of metabolic processes. The toxic effect can occur even at 5% concentration of the dye.
To reduce the toxic influence of wastewaters, containing dyestuffs such as methyl orange, various purification methods are used, including sorption. To increase the cost-effectiveness of the process, the sorbents, based of various industrial wastes, have found application lately. In the present research the material, based on black soldier fly (Hermetia Illucens) maggots’ vermiculture, was used.
According to experimental findings and the adsorption isotherm, the type of the sorption material’s pores and the type of sorption were determined. It has been demonstrated that the sorption material belongs to transition-porous sorbents, which is essential for extracting large molecules of the dye. According to the isotherm, the dye molecules sorption proceeds in stages: at first, a monolayer is formed, which is indicated by the first plateau in the isotherm. At the second stage, a multilayer in the form of dye molecules’ chains or clusters – the second plateau in the isotherm – is formed. The sorption mechanism is predetermined by the specific composition of zoocompost particles. Zoocompost is rich in humic compounds with such functional groups as ‒NH, ‒OH, ‒C=O. The presence of these groups makes it possible to adsorb anionic dyes, including methyl orange dye, due to electrostatic interactions or hydrogen bonding.
The influence of the sorbent’s weight, particles size, reaction mix temperature, duration of sorption process on methyl orange dye removal degree was studied. The sufficient efficiency of the process up to 90% was demonstrated.
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PHYSICO-CHEMICAL FEATURES OF THE PALLADIUM NANOCATALYSTS FORMATION ON COMBINED MATRICES-CARRIER FOR FUEL CELLS

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 58-66 p.
Abstract
The development of modern nanotechnological methods and approaches to the synthesis and formation of nanostructures allows us to create new materials that combine various functional properties and unique physical and chemical characteristics. Such structures include composite materials consisting of a structured matrix modified with various fillers. Currently, composites are of particular interest to researchers, in which nanoscale particles play the role of filler, which makes it possible to obtain catalysts with increased activity and stability. Commercial perfluorinated proton exchange membranes of the Nafion type and carbon-containing carriers (carbon nanotubes, graphene, fullerenes) are promising carrier matrices for chemical energy sources – fuel cells. Nanoparticles based on platinum, palladium, or their alloys are excellent materials for the reactions of electrocatalytic oxidation of hydrogen and oxygen reduction that occur in fuel cells. The elements based on the direct oxidation of formic acid mainly use bimetallic nanoparticles based on palladium, which exhibit higher catalytic properties. In this work, new effective polymer-carbon composites modified with palladium nanoparticles were synthesized. Single- and multi-wall carbon nanotubes were chosen as substrates. Physicochemical studies of the obtained materials were carried out using electron microscopy and small-angle X-ray light scattering. The sizes of nanoparticles in the composition of functional carrier matrices are determined. It was found that the carbon filler contributes to the better stabilization of small nanoparticles in the composition of the composite. The data on the influence of the conditions for the formation of metal nanoparticles on their size, shape and distribution over the matrix surface are obtained. The stability of samples with variable palladium loading on various carrier matrices was studied by chronoamperometry. The prospects of using the formed materials for fuel cell electrodes with direct oxidation of formic acid are proved.
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