CC BY
25
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, Doctor of Chemistry, professor director of Tashkent chemical-technological research institute
Bozorov Jurabek Turanovich, Ph D., associate professor, department Tashkent state technical university, "Geology of oil and gas fields" Mukolyants Arsen Artemovich, associate professor, department"Hydraulics and hydropower"
Tashkent state technical university E-mail: [email protected]
SYNTHESIS OF NEW ANTICORROSION COATINGS BASED ON GOSSIPOL RESIN
Abstract. 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 production ef- It is established that as a result of the interaction of gos-
ficiency, there is a necessity to develop new technologies that sypol resin and 3-chloroxypropane (ChOP), monoethanol-
ensure the integrated use of raw materials and the disposal of amine (MEA) and diethanolamine (DEA) stable modified
industrial waste, which, in turn, leads to preservation of raw anti-corrosion coatings are formed.
materials and improvement of the ecological situation. Synthesized anticorrosive compositions based on gossy-
At present, the need of the Republic of Uzbekistan for pol resin and 3-chloroxypropane (ChOP), which mechanism
anticorrosion materials is provided by import. Creating a tech- is characterized not only by the barrier type of protection, but
nological basis for waste chemical processing in order to ob- also by acquiring the properties of corrosion modifiers, also
tain import-substituting, anticorrosive commodity products have several advantages from the previous analogs:
for the needs of the country is relevant. - improved physical-mechanical and technological in-
This paper proposes development of physicochemical dicators;
and technological bases for the production of anticorrosive - high adhesive properties and resistance to aging;
materials from waste oil industry. - wide temperature range of plasticity, high heat and cold
On the basis of the experimental studies carried out us- resistance.
ing modern chemical and physicochemical methods, the In the production of cottonseed oil and fatty acids, lots
corrosion rate was determined by the polarization resistance of secondary products and wastes such as gossypol resin and
method on the corrosion rate meter P-5035. soapstock 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].
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 makes the presence 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 anticorrosion coating technology based on gossypol resin has been developed and introduced into production. Based on the use of cheap and affordable raw materials, the
zation 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 anticorrosion 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 anticorrosion materials are their high cost and low accessibility, as well as the impossibility of their use to combat multi component salt and acid corrosion.
The use of readily-available gossypol resin and its modifications as the basis of the anticorrosion 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 [3].
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 hexamethy-lenetetramine (CH2)6N4, monoethanolamine (MEA) and di-ethanolamine (DEA), which is one of the most well known representatives of acid corrosion inhibitors [4].
The fractionation study of gossypol resin, the identification of physical-chemical and mechanical characteristics have formed the basis for the development of sustainable anticorrosion compositions of a complex nature. Tablel shows the main parameters of the influence of the molar ratio of reagents on the composition of the product upon receipt of a polymeric anticorrosion inhibitor.
production of anticorrosion coatings has a high level of organi-
Table 1. - The influence of the molar ratio of reagents on the inhibitor composition of the oligomer antioxidant ChOP (T = 338°K, t = 2 h)
Molar ratio: Gossypol: ChOP. Output,% Average mol.mass. (cryoscopic) Element analysis,%
Car bon 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-chloroxypropane (ChOP) and HMTA, monoethanolamine (MEA) and diethanolamine (DEA) (compositions Mir K-1, Mir K-2, Mir K-3 and Mir 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 its 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 multi component media and acid solutions.
The optimal ratio of the composition components is defined. The corrosion behavior of the metal has been evalu-
ated by an electrochemical method in accordance with the standard СЭВ 4421-83 on samples made of carbon steel (St. 3) 40 x 40 x 160 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/m2 x h10-3) (Table 2).
Table 2.- Test samples for corrosion resistance in the presence of anticorrosion coating based on gossypol resin
Inhibitor GS, ChOP, MEA The d samp ifference in the e mass, g (day) Corrosion rate, g/m2^ 10-3 (day) Protective effect,% (day) The appearance of the sample after 90 days
7 28 90 7 28 90 7 28 90
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
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 Mir K system has the properties of reliable protection at concentrations of components, mass.%. Property evaluation of the composition as a rust converter modifier has been carried out based on GOST 6992-68 (Method for determination of weather-resistance of coatings) visually, according to an eight-
Table 3.- The stability of the protective
point scale. Coatings has been applied on unalloyed (a) and rusted (b) steel surfaces, about 1.0mm thick, resistance to the effects of distilled water and 3% solution № S.1 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
№ The name of the test Time, day Coatings
1 2 3 4 5
а б а б а б а б а б
3 1 2 2 1 2 1 1 2 3 2
1. Resistance of coatings to static exposure 5 2 1 2 1 2 1 2 1 2 3
to water at T=20 ± 2 °C 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 static effects of a № S1 solution T=20± 2 °C 3 5 7 10 1 1 1 2 2 1 2 2 2 2 2 2 2 2 2 2 1 1 2 2 2 2 2 2 2 1 3 2 2 2 2 2 3 3 4 3 4 4 4 4
182 1 1 2 2 1 2 1 2 3 4
3. Resistance of coatings to atmospheric 365 1 1 2 2 1 2 1 2 4 4
influences in the city 547 2 2 2 2 2 1 3 2 3 4
730 2 1 2 2 3 2 3 3 4 4
The rate of general corrosion has been estimated on a ten-point scale: the first type 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 No. S1 to 10 days, and weather resistance up to two years. For coating No. 5, salt resistance 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, it is possible to
Table 4.- Physical and mechanical properties
apply paintwork material, which is the main positive feature of the coating as a rust modifier.
The physical-mechanical indicators of anticorrosion coatings based on gossypol resin, calcium oxide, zinc oxide, phosphoric acid and hexamethylenetetramine are shown in (table 4).
of anticorrosion 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. Flashpoint, °C 315, without solvent
On with "Nefras" solvent
5. The adhesion strength metal shear (adhesion), MPa, not less 4.0
6. Impact resistance, N-m, not less 1.9
7. Bend, mm, not more 7.0
S. 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 resin with other inhibitors can form a thin, stable anticorrosive the obtained coatings meet the requirements for anticorro- coating with the carbon steel surface. sion coatings by their basic indicators. For example, fast dry- Thus, on the basis of the multi-tonnage waste of the fating time, impact strength, bending elasticity, high adhesion, and-oil industry - gossypol resin can be easily used as new and the possibility of applying a paint and varnish material raw material for the production of anticorrosive polymer on these coatings. composite materials. Coatings have been tested with a posi-Resumed on the foregoing, it can be considered that, due tive result in conditions of high salinity at "Mubarekneftegaz" to its specific property, the interaction products of gossypol's LLC.
References:
1. Алибеков Р. С. Антикоррозионные покрытия на основе госсиполовой смолы со свойствами модификаторов ржавчины: Автореф... дис. канд. хим. наук.- Т.: 2002.- 23 с.
2. Жуманиязов М. Ж., Курамбаев Ш. Р., Жуманиязова Д. М. Антикоррозионный состав для модификации ржавчины металлов // Журн. «Композицион материаллар»,- Ташкент. 2015.- № 4.- С. 47-49.
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. 1923.
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 г.- № 2.- С. 143-48.
