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Sapronova Zh.A.

Doctor of Engineering Sciences (Advanced Doctor), Professor, Belgorod State Technological University named after V.G. Shukhov

Kinetics and mechanism of adsorption of methylene blue dye by crushed sunflower biomass

https://doi.org/10.58224/2619-0575-2024-7-3-78-92
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 78 – 92 p.
Abstract
Objectives: to study the kinetics and mechanism of dye adsorption by cellulose raw materials. Methods. As a sorbent, waste from crop production was used – ground sunflower stalks, initial and modified with 10% NaOH alkali, with a particle size from 1 to 2 mm. Methylene blue dye was selected as an adsorbate by preliminary tests. Adsorption isotherms were constructed to determine the maximum sorption capacity. Kinetic models of sorption of the pseudo-first and pseudo-second order are constructed. In order to determine the mechanism of the process, thermodynamic constants were determined: sorption energy (E), Gibbs energy (ΔG) and Bio coefficient (Bi).
Results. The maximum sorption capacity of the crushed biomass of sunflower stalks in relation to the dye is 0.52 mmol/g for the alkali-modified material, which is 48% higher than the initial content (0.35 mmol/g). Thus, the SP(NaOH) material showed improved sorption properties, and it was selected for further kinetic studies. The sorp-tion energy is 5.82 kJ/mol, which may indicate physical adsorption. The Gibbs energy is -6.3742 kJ/mol, less than zero, which indicates the spontaneity of this process. The adsorption equilibrium for the MG dye occurs after 120 minutes, the kinetic curve has a smooth character. The Bio coefficient is 1.812, therefore, the adsorption process is limited by mixed diffusion.
Conclusions. The analysis of the data obtained made it possible to determine the Bio coefficient reflecting the course of MG adsorption by a mixed–diffusion mechanism over the entire time range of adsorption. This indicates the complex character of the MG adsorption process and confirms the importance of taking into account various factors influencing this process when developing methods for cleaning aquatic environments from organic pollu-tants.
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NICKEL IONS ADSORPTION BY THERMOMODIFIED FALLEN LEAVES OF CHESTNUT

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 48-59 p.
Abstract
In recent years, the attention of researchers has been attracted by industrial and agricultural waste, which can be used as sorption materials. A special group is made up of lignocellulose-containing components of woody biomass (leaves, bark, needles, fruits, etc.) and wood processing products (sawdust, shavings, chips, etc.). Advantages of using the latter as reagents for wastewater treatment include simple technique, small processing, good adsorption capacity, selective adsorption of heavy metal ions, low cost, free availability and easy regeneration. Trees foliage attracts attention аmong the components of the woody biomass, it has a large specific surface area and falls annually under the conditions of the Russian Federation, which facilitates its collection and use.
Nickel ions are one of the most toxic pollutants that enter water bodies with industrial wastewater. The infor-mation on the nickel compounds toxic effect on living organisms is briefly presented. In this work, we studied the sorption properties of chestnut fallen leaves (CFL) in relation to nickel ions. The sorption capacity maximum value of the thermally modified CFL at a temperature of 250° C (CFL250) is 1.3 mmol / g for nickel ions. By processing the obtained isotherm within the framework of the Langmuir, Freundlich, BET, Dubinin-Radushkevich sorption models, it was found that the adsorption process is most accurately described by the Langmuir model (R2 = 0.9912). The calculated Gibbs energy is equal to -7.86 kJ / mol, it indicates the occurrence of spontaneous physical adsorption of Ni2 + ions on the CFL250 surface.
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REMEDIATION OF SOILS CONTAMINATED WITH Cd2+ IONS BY ZOO COMPOST AFTER CULTIVATION OF HERMETIA ILLUCENS FLY LARVAE

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 34-45 p.
Abstract
One of the most toxic substances entering the soil due to anthropogenic impact is cadmium (Cd). When growing agricultural plants on soils contaminated with cadmium, it is possible for cadmium to enter the human body through food chains, which can cause numerous disturbances in the work of various body systems. In order to reduce the adverse effects of heavy metals on environmental objects, soil remediation is necessary. One of the types of remediation is a decrease in the mobility of pollutants and a decrease in their activity. In this paper, the possibil-ity of reducing the mobility of Cd2+ ions by adding zoo compost to contaminated soils after cultivating larvae of the “Black Soldier” fly (Hermetia illucens) was investigated. It was found that the content of Cd2+ ions in the mobile form in soils with the addition of zookompost significantly decreases compared to the control (up to 73.3% with a zookompost content of 2.5%). The sorption capacity of the zoo compost with respect to Cd2+ ions was determined, which is 0.12 mmol/g. The resulting sorption isotherm was processed within the framework of the monomolecular sorption models of Langmuir, Freundlich, Dubinin-Radushkevich. The values of sorption energy and Gibbs energy are calculated, the values of which indicate the course of spontaneous physical adsorption with chemisorption ele-ments.
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INTENSIFICATION OF THE COAGULATING SUSPENSION EFFECT ON THE EMULSION OF LIPID CONCENTRATE IN WATER

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 77-85 p.
Abstract
The coagulation treatment method is widely used for the effluents of various origins treatment. Substances-coagulants disrupt colloidal formations and contribute to the small particles aggregation, which leads to their precipitation and, as a consequence, a decrease in the organic substances content and the solution turbidity. The most widely used for this purpose are coagulants based on iron and aluminum. The Hermetia illucens insect is increasingly used to obtain chemical raw materials and valuable feed products for the poultry and fish cultivation. Production processes generate effluents contaminated with biodegradable substances, including components of larval fat. In this work, it was studied the coagulation purification possibility of fat-containing effluents from the production of lipid concentrate from the Hermetia illucens fly larvae by a coagulating suspension obtained from the electric arc steel-making furnaces dust, together with a co-coagulant – chestnut leaves carbonized at 400° C, which were used to increase the number of coagulation centers in the system.
The use of a coagulating suspension in the purification of model emulsions gives a low clarification effect (49% with the addition of 0.2 cm3 per 100 cm3 of the emulsion). It was found that the addition of finely dispersed carbon-ized leaves can significantly increase the cleaning efficiency. The best result was obtained by adding the carbonized chestnut leaves in an amount of 0.3 g together with 0.2 cm3 of suspension per 100 cm3 of liquid, while the clarification efficiency of the lipid concentrate model emulsion was 98%, at a pH of 8.
The main stage of coagulation occurs in the first 40 minutes of interaction, after which no changes are observed in the state of the system under study.
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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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THE USAGE OF VEGETABLE SORBENT FOR REMOVING CONGO RED DYE FROM TEST SOLUTIONS

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 44-55 p.
Abstract
The research findings of sorption purification of test water environment, containing Congo red dye, by using this crop farming waste as a sorption material have indicated that the maximum sorption capacity of its biomass amounts to 0.37 mmol/g. The electronic microscopy data and the research findings of physical-chemical and sorp-tion properties of a new vegetable sorption material, obtained from sunflower (Heliánthus ánnuus) stalks, are presented. The processing of the data demonstrated that the obtained adsorption isotherm of Congo red belongs to Type V isotherms according to classification by Brunauer-Deming-Deming-Teller (BDDT) or to the S-type, according to Giles’ classification. With that, adsorption process is the most accurately described by the Freundlich model, and the process proceeds on the heterogeneous surface of the sorption material.
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SORPTION PROPERTIES OF SYCAMORE LEAF LITTER IN RELATION TO METHYLENE BLUE DYE

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 5-13 p.
Abstract
Dyes are one of the widespread and hazardous contaminants that enter water bodies with wastewater. Reagent precipitation, ion exchange, coagulation, flotation, and other methods are used to remove dyes from aqueous environment. At the same time, sorption treatment is one of the most effective. The authors proposed to use sycamore leaves biomass for the dye "Methylene blue" extraction from aqueous environment. To investigate the process of adsorption of methylene blue by the leaves biomass, the sorption capacity of the material has been es-tablished; it is shown that the adsorption process is best described by the Freundlich model with a correlation co-efficient R2 = 0.9537.
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PURIFICATION OF STARCH-CONTAINING WASTEWATER

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 14-20 p.
Abstract
The paper considers the possibility of purification of starch-containing wastewater by thermally modified waste of sugar production – saturation sediment. Starchy wastewaters with a large amount of organic compounds quickly rot, create a favorable environment for the development of microorganisms, so these waters should be subjected to deep purification. Thermo-modified saturation residue (TMSR) is a fine black powder, the main component of which is CaCO3, formed during the chemical reaction between Ca (OH)2 and CO2 in saturation columns in the process of diffusion beet juicetreatment in sugar production. CaCO3 acts as a basis for the carbon layer, which covers the surface of the particles and formed during the calcination of TMSR through carbonization of organic substances contained in the original saturation sediment. The authors investigated the effect of some technological factors on the purification efficiency. It was established that 40 minutes at a temperature of the reaction medium of 20-30°C is sufficient for flow of the process. The purification efficiency of starchy wastewater systems reaches 88%.
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STUDYING THE PROCESS OF OIL-CONTAINING EMULSION PURIFICATION BY MEANS OF EXPERIMENT PLANNING METHOD

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 19-30 p.
Abstract
The process of oil-containing emulsion purification with chestnut tree waste (CTW) is considered. The factors influencing the process of purification with the application of a full factorial experiment are established. The mathematical model obtained under carrying out a full factorial experiment has the form of a linear equation. The results of the calculation are comparable with the results of the experiment. The data obtained allow conducting a process of water purification at optimal values of technological parameters.
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THE USE OF PEANUT PROCESSING WASTE AS A SORPTION MATERIAL

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 40-49 p.
Abstract
The paper presents the results of the study of the possibility of using peanuts waste processing as a sorption material. The literature data on the use of numerous materials as sorbents are given. Physico-chemical and structural-morphological features of peanut shells were investigated. The object of the study was methylene blue dye as a widely known and used substance, and the sorption capacity for methylene blue is an important characteristic of industrial sorbents. The adsorption capacity of the material is calculated and the adsorption isotherm is constructed. The sorption capacity of the original peanut shell by methylene blue was 0.22 mmol/g.
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