COMPOSITION FOR PURIFYING RESERVOIRS OF CYANOBACTERIA AND GREEN ALGAE

Abstract

COMPOSITION FOR PURIFYING WATER FROM CYANOBACTERIA AND GREEN ALGAE. The invention relates to the field of disinfection and purification of reservoirs contaminated with cyanobacteria and green algae.The composition for purifying water from cyanobacteria and green algae, comprising copper sulfate powder and a binding agent, i.e., a hydrophobizing agent, according to the invention, comprises, as a binding agent, a hydrophobizing melt in the form of a high-melting-point triglyceride fraction to provide the formation of a superhydrophobic coating with a contact angle of 155 to 165°, by adding the hydrophobizing melt to copper sulfate powder heated to a temperature of 60 to 70 °C, with the following component ratio, % by weight: copper sulfate: 85 to 97; hydrophobizing melt in the form of high-melting-point triglyceride fractions - the remainder, followed by uniform mixing, incubating at a temperature of 65 °C for no more than 5 minutes, cooling to room temperature, and grinding the resulting mixture to a dispersed state with a particle size of 50 to 250 µg. microns.

Description

[001] The invention relates to the field of disinfection and purification of reservoirs of cyanobacteria and green algae.

[002] A composition for purifying a reservoir comprising copper sulfate and excipients is known (CN104556477 (A), cl. C02F 1 / 28, 2015).

[003] A composite for the bactericidal treatment of reservoirs is additionally known (CN107473344 (A), cl. C02F 43 / 36, 2017) comprising copper sulfate and excipients.

[004] A common disadvantage of known technical solutions is the complexity, high costs and difficult preparation process of the composition, as well as insufficient efficiency in purifying vast reservoirs of cyanobacteria and green algae as a result of insufficient residence time on the water surface until the active substance is completely dissolved.

[005] A technical solution comprising embodiments of diffuse and suspended compositions for water purification from cyanobacteria and green algae is known (Union Patent No. 2687929, cl. C02F 103 / 04, 2019), one embodiment being the closest in terms of technical essence to the present one, comprising an active substance in the form of copper sulfate powder, a floating agent of saturated hydrocarbons, resinous materials, wax, natural or synthetic latex and combinations thereof, for example, in the form of sawdust or pitch, etc., a binding agent, i.e., a hydrophobizing agent, to form the coating of the active substance and a swelling agent.

[006] The process for preparing the composition includes the following steps: - Mix all the ingredients carefully; - then feed the resulting mixture to a granulator press of Petition 870220111445, dated 11 / 30 / 2022, pp. 75 / 88 2 / 12 mm in diameter, which produces spheres with a thickness of approximately 7 mm and a mass of approximately 500 mg; Next, incubate the spheres in an oven at 115°C for 3 minutes, remove from the oven, cool, and grind.

[007] The advantage of the known technical solution is that all forms of the compositions are suspended formulations of various bleaching agents that reduce the number of cyanobacteria populations in the treated water.

[008] However, the disadvantages of the known technical solution are: - use, as an active substance, of chlorine-containing agents that exhibit toxic properties when applied in large quantities as a result of a short dissolution period; - Use of a floating agent made of saturated hydrocarbons, resinous materials, wax, natural or synthetic latex, and combinations thereof, which partially or completely do not dissolve in water, polluting the reservoir after the active substance is no longer active; - use of a small amount of the active substance, which dissolves in 15 hours, as a result, the water must be treated several times, and which does not eliminate the residual toxicity of cyanobacteria and green algae; - complexity, which increases the cost of the composition.

[009] The objective of the invention is to provide a composition with an active substance content of at least 70%, which can remain on the surface of the water for a long time while maintaining solubility, with minimal toxic properties and contamination.

[010] The technical result of the claimed technical solution is to obtain a synergistic effect when cleaning vast reservoirs, due to the ability to remain on the water surface for a long time while maintaining solubility, the Petition 870220111445, dated 11 / 30 / 2022, pp. 76 / 88 3 / 12 less toxic properties and contamination, in addition to reducing costs and expanding the range of compositions for water purification from cyanobacteria and green algae.

[011] The technical result is achieved by the fact that the composition for purifying water from cyanobacteria and green algae comprising copper sulfate powder and a binding agent, i.e., a hydrophobizing agent, according to the invention comprises, as a binding agent, a hydrophobizing melt in the form of a high-melting-point triglyceride fraction to provide the formation thereof of a superhydrophobic coating with a contact angle of 155 to 165°, by adding the hydrophobizing melt to copper sulfate powder heated to a temperature of 60 to 70 °C, with the following component ratio, % by weight: Copper sulfate: 85 to 97 melted hydrophobizing agent in the form of high melting point triglyceride fractions - the remainder, followed by uniform mixing, incubating at a temperature of 65 °C for no more than 5 minutes, cooling to room temperature and grinding the resulting mixture to a dispersed state with a particle size of 50 to 250 microns.

[012] The novelty of the claimed composition is that, to achieve the technical result, a hydrophobic melt in the form of a high melting point triglyceride fraction is used as a binding agent to form a superhydrophobic coating based on the same with a contact angle of 155 to 165°, by means of surface crystallization under certain thermal conditions and qualitative states of the components that make up the composition.

[013] The scientific, technical and patent literature does not provide a set Petition 870220111445, dated 11 / 30 / 2022, pp. 77 / 88 4 / 12 of the features to solve a problem that previously could not be solved by known technical solutions. The state of the art does not provide inventions that have features that coincide with the distinctive features of the composition in question, which indicates that the composition meets the patentability criterion of inventive activity.

[014] The industrial applicability of what is claimed is due to the fact that the preparation of the composition is technically feasible and can be used to clean reservoirs of cyanobacteria and green algae.

[015] The essence of the invention is explained by drawings, where Fig. 1 (a) schematically shows the arrangement of the copper sulfate powder treated by the hydrophobic melt in relation to the fluid; (b) is a view of A; Fig. 2 shows a drop of water on the surface of the copper sulfate powder treated by the hydrophobic melt; Figs. 3.1 and 3.2 show the micrograph of copper sulfate powder particles treated by the hydrophobic melt (sample no. 4); Fig. 4 shows the test of sample no. 4 in water; Fig. 5 shows a micrograph of the crushed sample no. 4; Figs. 6.1 and 6.2 show the water treated by the composition on day 12 after treatment.

[016] The provisional title of the composition for purifying reservoirs of cyanobacteria and green algae is Vodagrad C.

[017] To obtain the composition, the following components were used: Active substance (AS): copper sulfate (cupric sulfate, blue copper), which is an inorganic compound, a copper salt in sulfuric acid with the chemical formula CuSO4. Non-volatile and odorless substance. A white powder, a very hygroscopic substance in its anhydrous form. Transparent and non-hygroscopic crystals of various shades of blue in the form of a crystalline hydrate. Copper(II) sulfate is highly soluble in water. Blue CuSO4-5H2O pentahydrate, i.e., blue copper, is crystallized from aqueous solutions. Petition 870220111445, dated 11 / 30 / 2022, pp. 78 / 88 5 / 12 It has disinfectant, antiseptic, and astringent properties. A hydrophobizing melt in the form of a high-melting-point triglyceride fraction was used as a binding agent. The hydrophobizing melt refers to the liquid state of the melt at a temperature between the critical melting point and the boiling point. [ 018] The choice of a hydrophobic agent for the preparation of the composition was made taking into account the following criteria: - The selected water-repellent agent, or more specifically a water-repellent-based coating, must have a contact angle of no less than 90°; - The hydrophobic agent must have a melting point of at least 25 °C, because at this temperature many fats (triglycerides) in the solid state exhibit good hydrophobization; - low cost of the hydrophobic agent; The hydrophobic agent must be safe.

[019] Research has shown that these requirements are met by palm oil-based emulsifiers for the food industry produced by Palsgaard® (https: / / www.palsgaard.ru / sustainable-emulsifiers / emulsifieroverview / ).

[020] These emulsifiers are high melting point triglyceride fractions.

[021] The composition for purifying reservoirs of cyanobacteria and green algae is prepared as follows.

[022] When copper sulfate powder is introduced into water, it slowly or rapidly, depending on the particle size, settles to the bottom, followed by its dissolution. To give the powder the ability to remain on the surface of the water, it is necessary to create superhydrophobic coatings characterized by contact angles of θe >150°. Thanks to these Petition 870220111445, dated 11 / 30 / 2022, pp. 79 / 88 6 / 12 coatings, an air layer 1 is created between the surface of the powder 2 and the liquid 3, which causes the material to be pushed to the surface of the water-air interface (Fig. 1), thanks to which a long residence time on the water surface is possible.

[023] Two main conditions must be met to create superhydrophobic coatings: 1. To create a dispersed (rough) surface structure, including the nanoscale level, through crystallization of the coating from the melt. 2. Hydrophobicize the surface so that the contact angles are greater than 90°.

[024] To create a superhydrophobic coating, 85 to 97 g of copper sulfate powder (blue copper) were taken per 100 g of the composition, uniformly heated to a temperature of 60 to 70 °C, and the melt of hydrophobic agent (palm oil-based food emulsifier) ​​was taken in an amount - the remainder up to 100 g at a temperature not exceeding 65 °C, which corresponds to an intermediate value between the critical melting point and the boiling point, and added by uniformly spraying the heated powder onto the surface using a spraying device, while uniformly mixing and incubating the same for not more than 5 minutes to crystallize the surface of the powder at a temperature not lower than the melting point (55 °C) of the palm oil-based food emulsifier (hydrophobic agent), followed by cooling to room temperature. The resulting mixture was then ground to a dispersed state with a particle size of 50 to 250 microns.The heating temperature of the copper sulfate powder (60 to 70 °C), melting of the hydrophobic agent (65 °C), as well as stirring and aging for no more than 5 min at a temperature below the melting point (55 °C) of the palm oil-based food emulsifier is conditioned by the fact that. Petition 870220111445, dated 11 / 30 / 2022, pages 80 / 88 7 / 12 This temperature combination provides uniform crystallization of the active agent powder surface.

[025] The composition was prepared using the following equipment: an overhead mechanical stirrer (https: / / www.ika.com / ru / Products-LabEq / Overhead-Stirrers-Agitator-Blender-Lab-mixer-csp-187 / ), an induction cooker, a stainless steel tank (10 L capacity), and a temperature sensor. A hammer mill was selected to be used as a dispersion device (https: / / infelko.ru / drobilki / drobilki-molotkovye-molot-200-400.html). The grinding parameters (motor power: 1.5 kW, material feed rate for grinding: not more than 200 g / min, internal grids with a pore size of 2 mm) were selected in order to obtain, at the output, a powder with a particle size ranging from 50 to 250 microns. The composition obtained in this way had a superhydrophobic effect characterized by a contact angle with water of 155 to 165°, as determined by the sliding of a drop over the resulting coating (Fig. 2).If water droplets roll across the surface of the copper sulfate powder coating and are not absorbed into it, the coating formation process is considered uniform.

[026] To determine the ideal amount of components to be included in the composition, 5 samples were created with different contents of the active substance and the hydrophobic melt, and experiments were conducted to determine the water contact angle of the superhydrophobic coating and the dissolution time of the composition by means of tests that were carried out simply by introducing the composition into water.

[027] The results are shown in Table 1. Table 1. Results of experiments to determine the water contact angle of the superhydrophobic coating and the dissolution time of the Petition 870220111445, dated 11 / 30 / 2022, pages 81 / 88 8 / 12 composition Sample No. Components Contact angle, θ,° Dissolution time, days Copper sulfate, % by weight Hydrophobic agent melt, % by weight 1 80 Remaining 145 3 2 85 Remaining 153 3.5 3 90 Remaining 157 5 4 97 Remaining 163 7 5 99 Remaining 175 —

[028] According to the data in the table, the longest dissolution and surface retention periods were observed in sample no. 4, with 97% copper sulfate content and 3% hydrophobic melt content. As sample no. 4 was the most effective, only this sample is shown in the graphic material. Fig. 4 shows that a small fraction of the material in sample no. 4, which apparently has a large particle size, settled to the bottom as a result of gravity prevailing over Archimedes' force. Furthermore, the solubility in water was not very high and the sample was completely dissolved in 7 days.

[029] Additionally, micrographs of the particles from sample no. 4 were analyzed to show that a discrete coating was formed, with a thickness of 100 to 200 nm (Figs. 3.1 and 3.2).

[030] After analyzing the dispersion of the initial blue copper and sample no. 4, it was determined that the particle size was in the range of 200 to 3000 microns. This size, according to the authors, negatively affects the suspensibility and solubility of the material and, therefore, sample no. 4 was ground to a degree of dispersion in the range of 50 to 250 microns, this size Petition 870220111445, dated 11 / 30 / 2022, pages 82 / 88 A particle size of 9 / 12 was the most effective. Particle size was controlled using the Klin grinding meter (http: / / www.defectoscop.ru / product84.html). The optical image of the ground sample #4 is shown in Figure 5.

[031] To prove the efficiency of the composition in question, pilot tests were conducted.

[032] The tests were conducted at the facilities of the All-Russian Research Institute of Biological Plant Protection (Krasnodar), at the tomato genetic collection laboratory.

[033] According to the work procedure, water samples from Lake Abrau were collected with a plankton grid (cloth no. 78) during the bloom of blue-green algae (cyanobacteria and green algae) in the water. To collect the biomass, the top 1-meter layer was filtered. Two weeks after cultivation, the water containing blue-green algae was poured into 20-liter cuvettes and the composition was added at the consumption rate, according to Table 2, to assess the impact on cyanobacteria.

[034] The experiment lasted 4 to 8 weeks.

[035] After applying the composition, the algae cells formed colonies on the surface and settled after some time. The water itself took on a bright blue color, which disappeared as the product settled. It was further observed that, when high doses are introduced, a portion of the product sediments and another portion remains on the surface. The color of the algae changed from bright green to grayish brown. 12 days after the introduction of the composition in the highest quantity (20 kg / ha), no formation of new colonies was observed on the bottom and walls of the container, the water remained clear, but with a yellowish tint (Figs. 6.1 and 6.2). Table 2. Doses of the composition in model reservoirs using biological material from Lake Abrau. Petition 870220111445, dated 11 / 30 / 2022, pages 83 / 88 10 / 12 Variant | Quantity of composition on the surface of the reservoir, kg / ha | Formation of new cyanobacteria colonies, 12 days after treatment | 1 | 2.25 | The bottom of the container is completely covered by cyanobacteria colonies | 2 | 4.25 | The bottom of the container is partially (70%) covered by cyanobacteria colonies | 3 | 6.25 | The bottom of the container is partially (40%) covered by cyanobacteria colonies | 4 | 10 | The bottom of the container is partially (20%) covered by cyanobacteria colonies | 5 | 20 | The bottom of the container is clean

[036] To evaluate the toxicity of the treated water, a garden cress (Lepidium sativum L.) bioassay was used.

[037] The bioassay was conducted in Petri dishes in triplicate for each sample. Filter paper discs were placed at the bottom of a Petri dish. In each dish, 30 garden cress seeds were placed on the surface of the substrate. The same filter paper discs were placed on top. The filter paper in all dishes was moistened with water from the test samples according to the variants of the experiment. One of the samples with distilled water is a control that was used in a comparative analysis with the phytotest indicators of the other samples in question. Seed germination was carried out in a thermostatic cabinet at a temperature of 20 to 25 °C for 7 to 10 days. At the end of the experiment, the phytotest parameters were measured: seedling length, average dry mass, germinability, germination power. The results are shown in Table 3. Table 3. Measured parameters of Lepidium sativum L. formed under the influence of the samples in question from Lake Abrau. Petition 870220111445, dated 11 / 30 / 2022, pages 84 / 88 11 / 12 Experiment variant Phytotest parameters (after the second introduction) Seedling length (mm) Dry weight (mg) Germinability on day 5 (%) Germination power (%) 1 112 1.22 90.7 80.5 2 125 1.38 93.0 82.5 3 143 1.54 95.3 88.8 4 152 1.60 95.5 92.0 5 162 1.64 96.2 92.0 control 164 1.76 96.6 94.2

[038] The studies conducted show an acute residual toxicity of the samples after cyanobacteria in variants with a minimum dose of the composition and show a decrease in the residual toxic properties of the samples after cyanobacteria with an increase in the dose of the composition.

[039] To confirm the conformity of the claimed technical solution with the patentability criteria, comparative analyses were conducted to determine the novelty of the features relating to the prototype (Table 4) and essential features of the composition that allow achieving the technical result (Table 5). Table 4. Examination of characteristics for novelty. Prototype Composition in question Water disinfection agents: chlorine-containing agents and copper sulfate powder Copper sulfate powder Floating (suspended) agent consisting of saturated hydrocarbons, resinous materials, wax, sawdust, natural or synthetic latex and combinations thereof, which are partially or completely insoluble in water. Not present The binding agent is hydrophobic glyceryl stearate which does not provide formation of a superhydrophobic coating based on it Hydrophobic melt in the form of a high melting point triglyceride fraction to ensure the formation of a superhydrophobic coating based on it Swelling agent Not present Petition 870220111445, dated 11 / 30 / 2022, pages 85 / 88 12 / 12 Table 5. Examination of the essential characteristics of the technical solution in question. Essential characteristics of the solution in question. New properties acquired as a result of using the characteristics. Positive effect achieved. The hydrophobic melt in the form of a high-melting-point triglyceride fraction forms a dispersed (rough) surface structure, including the nanoscale level, crystallizing the melt coating and hydrophobicizing the surface to ensure the formation of a superhydrophobic coating with a contact angle of 155 to 165°. 1. Obtain a synergistic effect due to a long residence time on the water surface with the preservation of solubility and less toxic and contamination properties of a reservoir. 2. Reduce costs. 3. Expand the range of compositions for water purification. Add the hydrophobic melt to copper sulfate powder heated to a temperature of 60 to 70 °C. Component ratio, % by weight: copper sulfate: 85 to 97%; hydrophobic melt: remainder.

[040] Thus, the results obtained from the pilot tests (Tables 1, 2, 3), as well as the examination of characteristics (Tables 4, 5) allow us to conclude that the composition in question showed high efficiency in purifying reservoirs of cyanobacteria and green algae.

Claims

1. Composition for purifying water from cyanobacteria and green algae, characterized by comprising copper sulfate powder and a binding agent, i.e., a hydrophobizing agent, which has the characteristic of comprising, as a binding agent, a hydrophobizing melt in the form of a palm oil-based food emulsifier to provide the formation of a superhydrophobic coating with a contact angle of 155 to 165°, by adding the hydrophobizing melt to copper sulfate powder heated to a temperature of 60 to 70 °C, with the following component ratio, % by weight: Copper sulfate: 85 to 97 melted hydrophobizing agent in the form of palm oil-based food emulsifier - the remainder, followed by uniform mixing, incubating at a temperature of 65 °C for no more than 5 minutes, cooling to room temperature and grinding the resulting mixture to a dispersed state with a particle size of 50 to 250 microns.

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