CC BY
59
Section 4. Technical sciences
https://doi.org/10.29013/AJT-20-5.6-26-31
Abdukarimov Mirzohid Muratovich, the senior researcher (basic doctor), Tashkent state technical university Yodgorov Normahmad, Doctor of Chemistry, professor," Tashkent state technical university Jalilov Abdulahad Turobovich, director of Tashkent chemical-technological research institute Doctor of Chemistry, professor, academic of science E-mail: [email protected]
SYNTHESIS OF NEW ANTICORROSION COATINGS BASED ON GOSSIPOL RESIN
Abastract. The article discusses the results of the study of the competitive anticorrosive coatings synthesis based on gossypol resin and phosphoric acid. The resistant modified anticorrosive coatings are presented as a result of the gossypol resin, 3-chloroxypropane, monoethanolamine and diethanolamine interaction. Synthesized anticorrosive compositions based on gossypol resin and 3-chloroxypropane, which mechanism is characterized not only by the barrier type of protection, but also by the acquisition of rust modifying properties with improved physical mechanical and technological indicators of high adhesive properties and aging resistance, as well as a wide temperature range of plasticity, increased heat and frost resistance have been obtained.
Keywords: gossypol resin, anticorrosion coatings, 3-chlor 1,2-oxypropane (ChOP), monoethanolamine (MEA), diethanolamine (DEA), urotropin, adhesion, range of plasticity, type of protection.
In connection with the need to improve produc- cal processing in order to obtain import-substituting,
tion efficiency, there is a necessity to develop new anticorrosive commodity products for the needs of
technologies that ensure the integrated use of raw the country is relevant.
materials and the disposal of industrial waste, which, This paper proposes devlopment of physico-
in turn, lead to preservation of raw materials and im- chemical and technological bases for the production
provement of the ecological situation. of anticorrosive materials from waste oil industry.
At present, the need of the Republic of Uzbeki- On the basis of the experimental studies carried
stan for anticorrosion materials is provided by im- out using modern chemical and physicochemical
port. Creating a technological basis for waste chemi- methods, the corrosion rate was determined by the
polarization resistance method on the corrosion rate meter R-5035.
It is established that as a result of the interaction of gossypol resin tnd 3-chloroxypropane (OCP), monoethanolamine (MEA) and diethanolamine (DEA) stable modified anti-corrosion coatings are formed.
Synthesized anticorrosive compositions based on gossypol resin and 3-chloroxypropane (OCP), which mechanism is characterized not only by the barrier type of protection, but also by acquiring the properties of corrosion modifiers, also have several advantages from the previous analogs:
- improved physical-mechanical and technological indicators;
- high adhesive properties and resistance to aging;
- wide temperature range of plasticity, high heat and cold resistance.
In the production of cottonseed oil and fatty acids, lots of secondary products and wastes such as gossypol resin and soap stock are generated. It is known that gossypol resin is an aromatic compound with phenolic, hydroxyl groups and a carbonyl group in ortho position to a hydroxyl group.
In the gossypol resin, 12% of nitrogen-containing compounds, 36% of gossypol conversion products, which retained naphthol hydroxyls and 52% of fatty and oxyfatty acids in the form of lactones, have been found [1].
The above mentioned resin exhibits acidic properties as well as properties of phenolic and aldehyde compounds. The presence of phenolic, carboxyl, carbonyl functional groups allows modification of gossypol resin and converts it to a water-soluble state [2; 3; 4; 5].
It is known that polyphenols, fatty acids, hydrocarbons, nitrogen- and phosphorus-containing compounds, as well as gossypol transformation products are present in the gossypol resin. The presence of naphthalene core compounds in its composition also makes the products of gossypol resin thermal, chemo- and radiation-resistant, and maket the pres-
ence of phenolic hydroxyls and aldehyde groups reactive with high complexing properties.
In many respects, it can successfully replace expensive anti-corrosion coatings, which deficit is felt every year. The preparation of anticorrosive materials on the basis of gossypol resin is associated with specific features and requires the search for certain conditions, as well as the use of non-traditional additives - modifiers [3].
In order to reduce costs and improve operational properties, an anti-corrosion coating technology based on gossypol resin has been developed and introduced into production. Based on the use of cheap and affordable raw materials, the production of anticorrosion coatings has a high level of organization of technological processes and relatively high economic efficiency.
One of the advantages of the obtained bitumen anticorrosive composite materials is their versatility. In particular, by selection of appropriate modifiers and solvents improved anti-corrosion coatings and paints can be obtained from them [4].
Today in domestic practice there are over 100 different compositions for inhibiting the corrosion of steel. The disadvantages of the existing anti-corrosion materials are their high cost and low accessibility, as well as the impossibility of use their to combat multicomponent salt and acid corrosion.
The use of readily-available gossypol resin and its modifications as the basis of the anti-corrosion coating is due to the fact that it contains phenol, hydroxyl and carboxyl groups that interact with corrosion products and bind iron ions into complex compounds of chelate structure [4].
In connection with the foregoing, gossypol resin is an effective material against corrosion, provided that the appropriate solvents are selected, and another synergistic enhancing inhibitor. To solve this problem, we have used hexamethylenetetramine (CH2)6N4, monoethanolamine (MEA) and diethanolamine (DEA), which is one of the most well-known representatives of acid corrosion inhibitors [5].
The fractionation study of gossypol resin, the of a complex nature. Table 1 shows the main param-
identification of physicochemical and mechanical eters of the influence of the molar ratio of reagents
characteristics have formed the basis for the devel- on the composition of the product upon receipt of a
opment of sustainable anticorrosion compositions polymeric anticorrosion inhibitor.
Table 1. - The influence of the molar ratio of reagents on the inhibitor composition of the oligomeric antioxidant GHOP. (T = 3380K, t = 2 h)
Molar ratio: Gossypol: HOP. Output^ Average mol.mass. (cryoscopic) Element analysis,%
Carbon Hydrogen
Calculated Found Calculated Found
3:1 72.3 2380 68.1 4.8
2:1 87.7 3450 67.9 5.2
1:1 98.8 4860 69.1 68.8 5.7 5.1
1:2 85.6 3820 69.3 4.9
1:3 79.2 3340 69.2 4.5
The inhibitory corrosion composition preparation method based on gossypol resin, 3-chloroxy-propane (OCP) and HMTA, monoethanolamine (MEA) and dietanolamine (DEA) (compositions Mir K-1, World K-2, World K-3 and World K-4), which solves the problem of eliminating the disadvantages. A distinctive feature is that the gossypol resin components are available, the preparation technology and it's use is simple an intermediate complex. The components can change the nature of the interaction of the metal surface with the surrounding corrosive medium individually or together and thereby, enhance the protective effect of the inhibitors. This technique is of particular relevance for the corrosion protection of metal structures in contact with multicomponent media and acid solutions.
Table 2. - Test samples for corn of anti-corrosion coating
The optimal ratio of the composition components is defined. The corrosion behavior of the metal has been evaluated by an electrochemical method in accordance with the standard СЭВ 4421-83 on samples made of carbon steel (St. 3) 40x40x160 mm in size, without corrosive lesions (standard), with corrosive lesions (thickness of corrosion products from 150 to 300 microns). The corrosion behavior of the samples has been evaluated by the nature of the anodic polarization curves. The obtained data have also been confirmed by the results of chemical analyzes. The rate of general corrosion has been estimated by weight loss per unit area per unit of time (g /m2xh10-3) (Table 2).
)sion resistance in the presence based on gossypol resin
Inhibitor HS, HOP, MEA. The difference in the sample mass, g (day). Corrosion rate, g / m2xx 10-3 (day). Protective ef-fect,% (day). The appearance of the sample after 90 days.
7 28 90 7 28 90 7 28 90
1 2 3 4 5 6 7 8 9 10 11
Without processing. 0.0105 0.0567 0.0696 44.4 56.16 22.08 - - - High corrosion.
91:2:0:2,0:4,5:0,5 0.0014 0.0067 0.0742 5.91 7.13 4.48 86.4 88.2 89.6 Medium corrosion.
90:2:2,0:5,5:0,5 0.0010 0.0089 0.0013 4.03 9.22 4.35 90.6 94.3 90.1 Traces of corrosion.
89:2:2,0:6,0:1,0 0.0001 0.0005 0.0009 0.41 0.46 0.29 99.0 99.2 98.2 Clean.
1 2 3 4 5 6 7 8 9 10 11
88:2:2,0:6,5:1,5 0.0007 0.0008 0.0014 3.47 5.27 1.64 98.2 98.1 97.2 Traces of Corrosion.
87:2:2,0:5,5:1,5 0.0014 0.0019 0.0025 5.1 7.35 3.19 97.2 96.5 95.5 Low Corrosion.
The test results show that the composition of the World K system has the properties of reliable protection at concentrations of components, masses.% property Evaluation of the composition as a rust converter modifier has been carried out on the basis of GOST-6992 visually, according to an eight-point scale. Coatings has been applied on unalloyed (a)
Table 3.- The stability of the protective
The rate of general corrosion has been estimated on a ten-point scale: corrosion rate <0.001 mm / year (perfectly resistant), 2 - from 0.001 to 0.003 mm / year, 3 - from 0.003 to 0.01 mm / year (very resistant), 4 - from 0.01 to 0.03 mm / year, 5 - from 0.03 to 0.1 mm / year (resistant), etc. (with each point, the corrosion rate increases by about 3 times). The 10th mark corresponds to a corrosion rate greater than 10 mm / year (non-resistant).
All obtained coatings are characterized by 1-2 points with water resistance up to 14 days, resistance to 3% solution NaC1 to 10 days, and weather resistance up to two years. For coating No. 5, salt re-
and rusted (b) steel surfaces, about 1.0 mm thick, resistance to the effects of distilled water and 3% solution NaC1 has been determined (Table 3). Weathering resistance has been measured in the atmosphere of the Aral Sea region, which has been considered to be a medium aggressive environment for two years.
properties of coatings in time in points
sistance is characterized by at least 120 hours, but water resistance up to 14 days and salt resistance up to 7 days have been practically observed.
In all cases, the coating durability was studied when applied to a rusty surface. At the same time, it should be noted that on samples of coatings deposited on rusty surfaces and tested in atmospheric conditions in accordance with the allotted time of the experiments, no partial rust clearing has been observed.
Probably, there was a modification of rust, due to the formation of carbon compounds, due to which, on a rusty surface, pre-treated with developed coatings,
№ The name of the test Time, Day Coverage.
1 2 3 5
1 Resistance of coatings to static a b a b a b a b a b
exposure to water at T = 20 ± 3 1 2 2 1 2 1 1 2 3 2
2 °C. 5 2 1 2 1 2 1 2 1 2 3
7 2 1 2 1 2 1 2 1 3 2
10 1 2 2 1 2 1 2 2 3 3
14 1 1 1 1 1 1 2 1 3 3
2 The resistance of coatings to the 3 1 2 2 2 1 2 2 2 3 4
static effects of a NaC1 solution 5 1 1 2 2 1 2 1 2 3 4
T = 20 ± 2 °C. 7 1 2 2 2 2 2 3 2 4 4
10 2 2 2 2 2 2 2 2 3 4
3 Resistance of coatings to atmo- 182 1 1 2 2 1 2 1 2 3 4
spheric influences in the city. 365 1 1 2 2 1 2 1 2 4 4
547 2 2 2 2 2 1 3 2 3 4
730 2 1 2 2 3 2 3 3 4 4
it is possible to apply paintwork material, which is the zinc oxide, phosphoric acid, and hex methylene tetmain positive feature of the coating as a rust modifier. ramine are shown in (Table 4).
The physical-mechanical indicators of anti-corrosion coatings based on gossypol resin, calcium oxide,
Table 4.- Physical and mechanical properties of anti-corrosion coatings based gossypol resin
№ The name of indicators Norm of indicators
1 Colour From light brown to brown
2 Appearance. Tar-like.
3 Smell Specific
4 Flash point, °C 315, without solvent
ON with Nefras solvent
5 The adhesion strength metal shear (adhesion), MPa, not less 4,0
6 Impact strength, p / gp, not less 1.9
7 Bend, tgp, no more 7.0
8 The interval of ambient temperature during application, °C 4-45
9 Hydrogen ion index (pH) 5.6-6.1
10 Crystallization temperature, °C Minus 40
11 Hiding power, g/m2, not more 100.0
12 Water absorption,%, not more 0.1
13 Drying time, h, not more 24
14 Expected protection period, days, in atmospheric conditions, not less 1000.0
15 Time of complete formation of the protective layer, days, not more 4-5
Based on the analysis of data (table 4) it can be stated that the obtained coatings meet the requirements for anti-corrosion coatings by their basic indicators. For example, fast drying time, impact strength, bending elasticity, high adhesion, and the possibility of applying a paint and varnish material on these coatings.
Based on the foregoing, it can be considered that, due to its specific property, the interaction products
of gossypol's resin with other inhibitors can form a thin, stable anticorrosive coating with the carbon steel surface.
Thus, on the basis of the multi-tonnage waste of the fat-and-oil industry - gossypol resin can be easily used as new raw material for the production of an-ticorrosive polymer composite materials. Coatings have been tested with a positive result in conditions of high salinity at «Mubarekneftegaz» LLC.
Список литературы:
1. Алибеков Р. С. Антикоррозионные покрытия на основе госсиполовой смолы со свойствами модификаторов ржавчины: Автореф... дис. канд. хим. наук.- Т.: 2002 г.,-23 с.
2. Юлдашев Н. Х., Жуманиязов М. Ж., Дюсебеков Б. Д., Ходжаев О. Ф., Курамбаев Ш. Р. Разработка антикоррозионного покрытия на основе госсиполовой смолы для защиты оборудования йо-до-бромной промышленности // Тез. докл. Межд. науч. конф. «Инновация-2003», - Т.: 2003. -С. 110-111.
3. Специальный технический регламент «Требования безопасности смолы госсиполовой» утвержден и введен в действие постановлением Узбекского Агентства стандартизации, метрологии и сертификации от 31.12.10 г. - № 1. - С. 19-23.
4. Алибеков Р. С., Дюсебеков Б. Д., Усенова С. О. Стандартизация физико-химического метода антикоррозионной устойчивости покрытия на основе госсиполовой смолы // Вестник Казанского технологического университета, 2013. - № 2. - С. 143-148.
5. Жуманиязов М. Ж., Курамбаев Ш. Р., Жуманиязова Д. М. Антикоррозионный состав для модификации ржавчины металлов // Журн. «Композицион материаллар», 2015. - № 4. - Ташкент. - С. 47-49.
