Multifunctional composition base 1,3-oxazinan-6-ones with corrosion inhibition and heavy organic compounds inhibition and dispersants and obtaining process

Abstract

Base compounds including 1,3-oxazinan-6-one derivatives of N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl propionic acids and paraformaldehyde, and their application as corrosion inhibitors with multifunctional properties serving as inhibitory/dispersant of asphaltene in production processes, transportation, refining and storage of crude oil and derivatives. The corrosion inhibitor with inhibitory/dispersant of asphaltenes properties comprises an active substance base of 1,3-oxaninan-6-ones and hydrocarbon solvents such as benzene, toluene, mixed xylenes, o-xylene, m-xylene and p-xylene, diesel, kerosene, jet fuel, alcohols, aliphatic branched and unbranched alcohols containing from 3 to 10 carbon atoms, such as isopropanol, butanol and pentanol, and mixtures of hydrocarbon solvents with aliphatic branched or unbranched liquid fuels. In addition, a process for obtaining 1,3-oxazinan-6-ones derivatives of N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl propionic acids and paraformaldehyde is described.

Claims

1. A process for obtaining 1,3-oxazinan-6-one by the following synthesis route: ##STR00006## and including two stages of reaction: I) a first stage of reacting an alkyl or alkenyl or cycloalkyl or aromatic amine of Formula I with an alpha-beta unsaturated carboxylic acid of formula II in the absence of a solvent to obtain the corresponding N-alkyl or N-alkenyl car N-cycloalkyl or N-aryl propionic acid of structural formula III, and II) a second stage of reacting said corresponding N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl propionic acids of structural formula III with paraformaldehyde of structural formula IV in the absence of a solvent or in the presence of an inert hydrocarbon selected from the group consisting of toluene, xylene, kerosene, and jet fuel to obtain the corresponding 1,3-oxazinan-6-ones of structural formula V, wherein R is a linear or branched alkyl chain of 6 to 18 carbons, a linear or branched chain alkenyl of 8 to 20 carbons or aromatic cycloalkyl having 5 to 12 carbons, R.sub.1 is a radical selected from the group consisting of H and CH.sub.3, and R.sub.2 is a radical selected from the group consisting of H and CH.sub.3.

2. The synthesis process of claim 1, wherein a molar ratio of said alkyl or alkenyl or cycloalkyl or aromatic amine of Formula I with respect to said alpha-beta unsaturated carboxylic acid of Formula II is in the range of 1:5 to 5:1 in the absence of solvents.

3. The synthesis process of claim 1, wherein a reaction time in said first stage is in the range of 1 to 24 hours.

4. The synthesis process of claim 1, wherein a reaction temperature of said first stage is in the range of 80 to 200 C.

5. The synthesis process of claim 1, wherein said alkyl or alkenyl or cycloalkyl or aromatic amine of Formula I is selected from the group consisting of hexylamine, heptylamine, octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine, oleylamine, linoleylamine, eurocylamine, behenylamine, taloylamine, cyclohexylamine, aniline, and benzylamine.

6. The synthesis process of claim 1, wherein said alpha-beta unsaturated carboxylic acid of formula II is selected from the group consisting of acrylic acid, methacrylic acid, crotonic acid and isocrotonic acid.

7. The synthesis process of claim 1, wherein a molar ratio of said N-alkyl, N-alkenyl, N-cycloalkyl or N-aryl propionic acid and said paraformaldehyde is 1:0.5 to 1:4.

8. The synthesis process of claim 1, wherein a reaction temperature of said second stage is in the range of 60 to 200 C. and a pressure in said second stage is in the range of 60 to 760 mmHg.

9. The synthesis process of claim 1, wherein a molar ratio of said N-alkyl, N-alkenyl, N-cycloalkyl or N-aryl propionic acid and said paraformaldehyde is 1:1 to 1:2, a reaction temperature of said second stage is 90-180 C. and a reaction pressure in the second stage is 400 to 555 mmHg.

10. A process for obtaining 1,3-oxazinan-6-one by the following synthesis route: ##STR00007## and including two stages of reaction: I) a first stage consisting of reacting an alkenyl amine of Formula I with an alpha-beta unsaturated carboxylic acid of formula II to obtain the corresponding N-alkenyl propionic acid of structural formula III in the absence of a solvent, and II) a second stage consisting of adding paraformaldehyde of structural formula IV to said N-alkenyl propionic acid of structural formula III, and reacting said corresponding N alkenyl propionic acids of structural formula III with said paraformaldehyde of structural formula IV to obtain said corresponding 1,3-oxazinan-6-ones of structural formula V, wherein R is a linear alkyl chain having 18 carbons, R.sub.1 is H, and R.sub.2 is H.

11. The process of claim 1, wherein the molar ratio of the said alkyl, alkenyl, cycloalkyl or aromatic amine of Formula I with respect to said alpha-beta unsaturated carboxylic acid of Formula II is in the range of 1:1 to 2:1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) It provides the following FIG. 1, in order to clearly understand the test of inhibition of corrosion of base compounds 1,3-oxazine-6-ones and their application as multifunctional corrosion inhibitors and inhibitor/dispersants of heavy organic compounds, and serving as a reference in the example application.

(2) FIG. 1 shows the inhibition test device consisting of a test specimen (A), a digitally controlled stirrer (B), a cover of poly (tetrafluoroethylene) (C), a glass (D) hydrocarbon-water mixture (E).

DESCRIPTION OF THE INVENTION

(3) New compounds were developed base 1,3-oxazinan-6-ones derivatives of N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl amino propionic acids and paraformaldehyde, and their application as multifunctional corrosion inhibitor with inhibitory and dispersant asphaltenes properties in production processes, transportation and oil refining, and transport and storage of hydrocarbons, with the following structural formula (4):

(4) ##STR00003##

(5) In the structural Formula (4), R is a linear or branched alkyl chain of 6 to 18 carbons or a linear or branched chain alkenyl of 8 to 20 carbons or aromatic cycloalkyl of 5 to 12 carbons, R.sub.1 is a radical that can be represented by the groupsH, or CH.sub.3 and R.sub.2 is a radical that can be H or CH.sub.3.

(6) The compounds of this invention were prepared according to the following scheme (5).

(7) ##STR00004##

(8) In the above reaction scheme, Reaction Product V corresponds to the compound of Formula (4). In the reaction scheme, R, R.sub.1 and R.sub.2 are as defined above.

(9) The first stage of the obtaining process is the reaction between an alkyl or alkenyl or cycloalkyl or aromatic amine of Formula I with an alpha-beta unsaturated carboxylic acid of formula II to obtain the corresponding N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl propionic acid of structural formula III. The molar ratio of amine alkyl or alkenyl or aromatic carboxylic acid with respect to alpha-beta unsaturated may vary in the range of 1:5 to 5:1, preferably in the range of 1:1 to 2:1 and the reaction is carried out in the absence of solvents. The reaction time and temperature depends on the structure of the alkyl or alkenyl or cycloalkyl or aromatic amine and alpha-beta unsaturated carboxylic acid, and the temperature at which the reaction is carried out. Usually the reaction time varies in the range of 1 to 24 hours and the reaction temperature varies in the range of 80 to 200 C.

(10) For alkyl amines can be selected from the following examples: hexylamine, heptylamine, octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine or a linear or branched alkenyl amine selected examples: oleylamine, linoleylamine, eurocylamine, behenylamine and taloylamine, or a cycloalkyl or aromatic amine derivative of the examples: cyclohexylamine, benzylamine, aniline, among others.

(11) With respect to acid alpha-beta unsaturated carboxylic preferred for this invention are: acrylic acid, methacrylic acid, crotonic acid and isocrotonic acid.

(12) The second stage of the production process consists of reacting the corresponding N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl propionic acids with paraformaldehyde in the structural formula IV to obtain the corresponding 1,3-oxazinan-6-ones derived of structural formula V. The molar ratio of N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl amino propionic and paraformaldehyde can vary in the range of 1:0.5 to 1:4 preferably in the range of 1:1 to 1:2 and reaction can be carried out in bulk or in the presence of an inert hydrocarbon solvent among which are preferably toluene, xylene mixtures, o-xylene, m-xylene, p-xylene, kerosene and jet fuel. The reaction time depends on the structure of N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl propionic acids, as well as temperature and pressure at which the reaction is carried out. Usually the reaction time varies in the range of 1 to 24 hours, the reaction temperature varies in the range of 60 to 200 C., preferably in the range of 90 to 180 C. and pressure which holds the reaction varies in the range of 60 to 760 mmHg, preferably in the range of 400 to 585 mm Hg. Paraformaldehyde is a condensation reaction product of formaldehyde having the formula

(13) ##STR00005##
having a typical degree of polymerization of 8-100.

(14) The compounds of the present invention and their formulations are useful as: Additives are added in crude oil and fuel oil as fuel without desulfurizing, fuel with low sulfur, diesel, methyl tertbutyl ether, alkylated gasoline, kerosene and jet fuel, to prevent and control corrosion in wells, pipelines and tanks storage. The additive concentration needed to control corrosion of ferrous metals depends on the type of oil or fuel oil derivative thereof, and the presence of other additives.

(15) Additives are added in crude oil and products derived from them to prevent and control the deposition of asphaltenes in wells, pipelines and refining plants. The additive concentration needed to control the deposition of asphaltenes depends on the type of crude oil or derivative thereof, and the presence of other fuel additives.

(16) In general, the concentration of the compounds of this invention varies in crude oil in the range 1 to 2000 parts per million (ppm), preferably from 1 to 1000 ppm.

(17) When another class of additives that control the deposition of organic compounds is present, a smaller amount of additive may be used, and in the case of fuel varies in the range of 1 to 50 parts per million (ppm), preferably from 1 to 20 ppm.

(18) The 1,3-oxazine-6-ones of the present invention can be formulated as a concentrate using inert organic solvent having a boiling point between 75 and 300 C., preferably hydrocarbon solvents such as benzene, toluene, mixed xylenes, o-xylene, m-xylene and p-xylene, diesel, kerosene, jet fuel, alcohols, aliphatic branched and unbranched containing in its structure from 3 to 10 carbon atoms, such as isopropanol, butanol and pentanol, and mixtures of hydrocarbon solvents with aliphatic branched and unbranched. The amount of active compound of Formula 4 in the formulation ranges from 10 to 90 wt %, preferably from 25 to 75 wt %.

(19) The 1,3-oxazine-6-ones of the present invention can be dosed from 5 to 2000 ppm, depending on conditions of operation of the well or the pipe containing the crude oil or liquid fuel.

EXAMPLES

(20) Here are some practical examples for better understanding of the present invention, without limiting its scope.

Example 1

(21) Process for obtaining 3-(octadec-9-enyl)-1,3-oxazine-6-one (Product 1). In a flask ball three-necked 500 ml equipped with a magnetic stirrer, a dropping funnel, a thermometer and a condenser were added 50 g (0.187 mol) of oleylamine at a temperature of 40 C. with vigorous stirring was slowly added to 13.48 g (0.187 mol) acrylic acid. The reaction is exothermic and the temperature under these conditions rises gradually to 90 C. The reaction mixture was stirred under these conditions for 2 hours and then increased to 100 C., thus obtaining a very viscous pale yellow, then to a temperature of 30 C. were added 2.8 g (0.094 mol) of paraformaldehyde, and temperature was increased to 93 C. at a pressure of 465 mmHg to remove water of reaction and finally obtained 65 g of Product 1, the spectroscopic features are:

(22) FTIR (cm.sup.1): 3004.9, 2921.6, 2852.1, 1656.1, 1463.5, 1376.9, 1305.4, 1106.1, 956.9, 721.2. .sup.1H NMR (CDCl.sub.3), 200 MHz, (ppm): 5.28, 3.91, 3.24, 2.84, 2.36, 1.94, 1.21, 0.82. .sup.13C NMR (CDCl.sub.3), 50 MHz, (ppm): 167.3, 129.7, 129.6, 68.4, 52.4, 48.1, 44.7, 32.5, 31.8, 29.4, 29.2, 27.0, 22.5 y 13.9.

Example 2

(23) Process for obtaining the 3-octadecyl-1,3-oxazine-6-one (Product 2). In a flask ball three-necked 500 ml equipped with a magnetic stirrer, a dropping funnel, a thermometer and a condenser were added 50 g of octadecylamine and at a temperature of 40 C. with vigorous stirring was slowly added to 13.4 g of acrylic acid. The reaction is exothermic and the temperature under these conditions rises gradually to 90 C. The reaction mixture was stirred under these conditions for 2 hours and then increased to 100 C., thus obtaining a very viscous pale yellow, then at a temperature of 30 C. were added 2.8 g of paraformaldehyde, and increase temperature at 93 C. at a pressure of 465 mmHg to remove water of reaction and finally obtained 64 g of Product 2, the spectroscopic features are:

(24) FTIR (cm.sup.1): 2922.1, 2852.1, 1655.3, 1461.5, 1375.8, 1302.6, 1105.7, 956.5, 721.3. .sup.1H NMR (CDCl.sub.3), 200 MHz, (ppm): 3.93, 3.25, 2.86, 2.38, 1.20, 0.83. .sup.13C NMR (CDCl.sub.3), 50 MHz, (ppm): 167.4, 68.4, 52.5, 48.2, 44.8, 31.8, 29.6, 29.5, 22.6, 22.5 y 14.0.

Example 3

(25) Process for obtaining the 3-tetradecyl-1,3-oxazine-6-one (Product 3). In a flask ball three-necked 500 ml equipped with a magnetic stirrer, a dropping funnel, a thermometer and a condenser were added 50 g of tetradecylamine and at a temperature of 40 C. with vigorous stirring was slowly added to 16.7 g of acrylic acid. The reaction is exothermic and the temperature under these conditions rises gradually to 90 C. The reaction mixture was stirred under these conditions for 2 hours and then increased to 100 C., thus obtaining a very viscous pale yellow, then to a temperature of 30 C. were added 3.5 g of paraformaldehyde, and increase temperature at 93 C. at a pressure of 465 mmHg to remove water of reaction and finally obtained 69 g of Product 3, the spectroscopic features are:

(26) FTIR (cm.sup.1): 2921.4, 2853.4, 1657.1, 1462.3, 1375.3, 1304.5, 1108.2, 955.8, 722.4. .sup.1H NMR (CDCl.sub.3), 200 MHz, (ppm): 3.95, 3.21, 2.85, 2.33, 1.23, 0.86. .sup.13C NMR (CDCl.sub.3), 50 MHz, (ppm): 167.1, 68.6, 52.7, 48.1, 44.6, 31.9, 29.7, 29.6, 22.7, 22.5 y 14.0.

Example 4

(27) Process for obtaining the 3-dodecyl-1,3-oxazine-6-one (Product 4). In a flask ball three-necked 500 ml equipped with a magnetic stirrer, a dropping funnel, a thermometer and a condenser were added 50 g (0.187 mol) of dodecylamine and a temperature of 40 C. with vigorous stirring was slowly added to 19.4 g of acrylic acid. The reaction is exothermic and the temperature under these conditions rises gradually to 90 C. The reaction mixture was stirred under these conditions for 2 hours and then increased to 100 C., thus obtaining a very viscous pale yellow, then to a temperature of 30 C. were added 4.1 g of paraformaldehyde, and increase temperature at 93 C. at a pressure of 465 mmHg to remove water of reaction and finally obtained 72 g of Product 4, the spectroscopic features are:

(28) FTIR (cm.sup.1): 2921.6, 2852.4, 1654.1, 1461.9, 1373.4, 1303.6, 1109.5, 951.5, 723.2. .sup.1H NMR (CDCl.sub.3), 200 MHz, (ppm): 3.97, 3.26, 2.83, 2.37, 1.15, 0.79. .sup.13C NMR (CDCl.sub.3), 50 MHz, (ppm): 167.2, 68.4, 52.2, 48.2, 44.4, 31.7, 29.5, 29.4, 22.5 y 13.9.

Performance Testing

(29) To evaluate the efficiency of corrosion inhibition in an environment characteristic of pipes and tanks that transport and store crude oil, used the gravimetric technique known as dynamic testing of wheel and electrochemical technique known as linear polarization. The following describes each test procedures and results.

Determination of the Corrosion Inhibition Efficiency Through NACE 1D-182 Method

(30) Gravimetric test is commonly called dynamic wheel (Wheel test) that simulates the corrosive environment characteristic of oil production, is a dynamic procedure developed for fluids (oil, water and inhibitor).

(31) For this test using a specimen of 1010 carbon steel with dimensions 2,5401,270 cm0.025 cm, which is weighed and placed inside a bottle containing 180 ml of an emulsion or brine aggressive environments simulating acids characteristic of the oil industry, and a certain amount of corrosion inhibitor can vary from 0 to 500 ppm. The bottle is sealed and placed in a hole of a wheel of 58.4 cm in diameter that is within a range, then the oven temperature is increased to 70 C., while the wheel rotates at 30 rpm for about 46 hours. At the end of the test, specimen is removed from the bottle, washed consecutively with chloroform, acetone, water, a solution of diluted hydrochloric acid, a potassium bicarbonate solution with 5 in weight and water, clean with wire brushing, rinse with soap and water, dried in an oven at 60 C. and reweighed. Depending on weight loss and with reference to a target is calculated efficiency of corrosion inhibition, while for the evaluation of the corrosion rate reported in thousandths of an inch per year (mpy) are taken into account the following parameters the specimen: a) weight loss, b) area, c) density d) test time.

(32) Gravimetric test is commonly called dynamic wheel (Wheel test) that simulates the corrosive environment characteristic of oil production, is a dynamic procedure developed for fluids (oil, water and inhibitor).

Testing Equipment and Reagents

(33) a) Evaluating dynamic for corrosion inhibitors with temperature controller, stirrer speed of 30 rpm and capacity for 52 bottles of 180 ml.

(34) b) Bottles of 200 ml capacity.

(35) c) Coupon SAE 1010 carbon steel, dimension 2,5401,2700.025 cm (10.50.010).

(36) d) Glassware for the preparation of a corrosive environment. This consists of a glass reactor of 2 liter, equipped with a cooling bath, mechanical stirrer, bubbler for gas (nitrogen and hydrogen sulfide), has an outlet connected to two traps in series (the first with sodium hydroxide in pellet form and the second with another sodium hydroxide solution 20% in weight), so that hydrogen sulfide does not contaminate the environment.

(37) e) Potentiometer for measuring pH.

(38) The test conditions are shown in Table 1, while the composition of the brine used is shown in Table 2.

(39) TABLE-US-00001 TABLE 1 Test Conditions, NACE 1D-182 method Temperature 70 C. Aqueous medium Synthetic brine with 600 50 ppm de H.sub.2S Test time 46 hours Organic medium Kerosene Volume ratio 90/10 Synthetic brine/organic medium Test volume 180 ml pH 4 Metals coupons Steel SAE 1010

(40) TABLE-US-00002 TABLE 2 Brine composition used, 1D-182 NACE method. Amount Salts (g/l) NaCl 60.0 CaCl.sub.2H.sub.2O 6.0 MgCl.sub.26H.sub.2O 10.48 Na.sub.2SO.sub.4 3.5

Results

(41) The difference in weight of the coupons before and after being exposed to corrosive liquid for 46 hours, is a direct indication of metal lost due to corrosion.

(42) The efficiency of corrosion inhibition is obtained by comparing the reference coupon wear with the wear of the coupons with corrosion inhibitor at different concentrations, using the following formula:
%E=(VoV/V100
Where:

(43) Vo=Corrosion velocity of reference coupon

(44) V=Corrosion velocity of coupon with corrosion inhibitor

(45) Table 3 shows the results of the Products 1 to 6 at different concentrations.

(46) TABLE-US-00003 TABLE 3 Concentration Corrosion velocity, Efficiency, Example (ppm) (mpy's)* (%) Reference 0 41.6 0 Product 1 10 2.2 94.9 25 3.5 91.9 50 2.4 94.5 75 2.0 95.2 Product 2 10 5.8 86.4 25 4.2 90.1 50 2.8 91.4 75 0.6 98.5 Product 3 10 4.6 89.3 25 1.4 96.7 50 1.4 96.7 75 1.6 95.9 Product 4 10 32.4 24.3 25 26.4 38.2 50 5.2 87.9 75 2.9 93.0 *mpy's: thousandths of an inch per year

Determination of the Efficiency of Corrosion Inhibition by the Method NACE-0172

Test Description

(47) Test Method NACE-0172 is to determine the corrosive properties of gasoline, jet fuel and distillate fuels that found in pipelines and storage tanks. Also includes information on metal specimen preparations, equipment and a system for ranking the test samples with corrosion inhibitor.

Testing Equipment and Apparatus

(48) The apparatus consists of: A temperature measuring device, and One bathroom. Should be used a thermally controlled bath of mineral oil capable of maintaining a temperature in the test sample 381 C. The bathroom must have a cover with holes to accommodate the test glass and the temperature measuring device.

(49) The test device used by the NACE-0172 method to determine the efficiency of corrosion inhibition posed by gemini surfactants of the present invention, illustrated by FIG. 1, consists of a test specimen (A), a digitally controlled stirrer (B), a cover of poly (tetrafluoroethylene) (C), a glass (D), and hydrocarbon-water mixture (E).

(50) The sample must be a steel yarn 81.012.7 mm, the steel shall conform to UNS*G10150 (Grade 1015), UNS G10180 (1018), UNS G10200 (1020) or UNS G10250 (1025) ASTM A108, used with a plastic handle of poly(tetrafluoroethylene) (PTFE). (*Unified Numbering System).

Test Procedure

(51) Add 300 ml of fuel to the test vessel and dispensed corrosion inhibitor to the desired concentration, the glass is placed in an oil bath at a temperature of 381 C. after 30 minutes of continuous stirring add 30 ml of distilled water, and agitation continued for three hours. Subsequently the sample is removed, and left to drain and washed with toluene or xylene followed by acetone.

Sample Qualification

(52) The rating should be based solely on the portion of the sample that remained in the test fluid. The corrosion products formed during the test have had limited opportunity to darken, and all deposits of solids not removed by washing of toluene and acetone should be considered as products of corrosion. Marks on the circle can occur during polishing and should not be interpreted as corrosion, classification is based according to Table 4.

(53) TABLE-US-00004 TABLE 4 Samples qualification NACE TM-0172 method. Qualification Percentage of corroded surface A 0 B++ Less than 0.1 (2 or 3 spots of no more than 1 mm in diameter). B+ Less than 5 B 5-25 C 25-50 D 50-75 E 75-100

(54) Table 5 shows the results of Product 1 with a variety of liquid fuels.

(55) Table 6 shows the results of the Products 2 to 6 on gasoline with low sulfur content at different concentrations.

(56) TABLE-US-00005 TABLE 5 Concentration, Test medium, Qualification, Product (ppm) (fuel) (NACE TM-0172) Reference 0 All fuels E 1 10 Primary gasoline B++ (without desulfurization) 10 Magna gasoline A 10 Premium gasoline A 10 Diesel B++ 10 MTBE A 10 Alkylated gasoline A 10 Magna gasoline/ A Ethanol (50:50)

(57) TABLE-US-00006 TABLE 6 Concentration, Qualification, Product (ppm) (NACE TM-0172) Reference 0 E 2 10 B++ 25 A 3 10 B+ 25 A 4 10 B+ 25 B++

Determination of the Efficiency of Corrosion Inhibition by Electrochemical Techniques

Equipment Used

(58) It used a glass electrochemical cell, reference electrode, working electrode, counter electrode, ph meter, multimeter, potentiostat/galvanostat Autolab PGSTAT 30 71410. Was also held for the preparation of the bitter brine of pH 4, and the dissolution of chemicals in isopropanol in order to prepare a solution of 1,000 ppm in 100 mL.

Test Procedure

(59) A specimen of carbon steel 1010 with area of 0.5 cm.sup.2 is grinding with #600 sandpaper. The bitter brine is the same as was used for the gravimetric technique. Polarization curves were generated linear open-circuit potential 25 mV. When the test is obtained polarization curve, which is analyzed to determine the corresponding corrosion rate. To make a new experiment is necessary to perform the roughing electrode is placed in the cell and generate another curve. This procedure is repeated until there is a coincidence of at least two curves. The experiments were performed at room temperature with magnetic stirring and bitter brine adjusted to pH 4.01. The corrosion rate (mpy) is determined through manipulation of the curve using the program of the potentiostat.

(60) Table 7 shows the results for Products 1 to 4 at different concentrations:

(61) TABLE-US-00007 TABLE 7 Corrosion Concentration, velocity, Efficiency, Product (ppm) (mpy's) (%) Reference 0 72 0 1 25 18 75 50 12 83 2 25 21 71 50 18 73

(62) Performance evaluation as inhibitors of precipitation or deposition of asphaltenes and asphaltene aggregates as dispersing the compounds of the present invention is carried out through two different tests:

(63) I) Test measuring the mass deposited on metal surface through an electrostatic field and,

(64) II) Measurement test asphaltenes dispersed in heptane-crude oil through UV-Visible spectroscopy. Measuring the dispersion of asphaltenes in crude oil-heptane mixtures.

I) Test Measuring the Mass Deposited on Metal Surface Through an Electrostatic Field

(65) This test consists of inducing the deposition of organic material on a metallic surface by means of applying an electrostatic field. The asphaltenic aggregates suspended in crude oil, in spite of not possessing a net electrical charge, due to their electronic density, are sensitive to electrostatic fields having certain intensity, which generates an electrostatic charge in them that induces their deposition on the plate connected to the positive pole of the potentiometer. A Teflon array, having two parallel metallic stainless steel plates separated by 5 mm, is introduced to each cell; the system is balanced at the test temperature, and the electric field is applied during 24 h, by the end of which, the plates (previously weighted) are removed from the cells and left to drain for 8 h, to afterwards be weighted and the quantity of deposited material to be determined. The efficiency of the compound is determined relative to the difference between the mass deposited on the plate from the sample without inhibitor, the reference, and the mass deposited from a crude sample with inhibitor.

(66) $\mathrm{Efficiency}=\frac{\mathrm{Reference}\mathrm{mass}\mathrm{deposition}-\mathrm{Inhibitor}\mathrm{mass}\mathrm{deposition}}{\mathrm{Reference}\mathrm{mass}\mathrm{deposition}}$

(67) Test conditions: Temperature: 50 C. Pressure: 0.0774 MPa (ambient) Crude petroleum sample volume: 500 cm.sup.3 Voltage: 800 V Amperage: 3000 mA Inhibitor dosage: 1000 ppm (mg/L) Oil (sample A)

(68) Below are shown in Table 8, the characteristics of the oil (Sample A) used in the tests I and II.

(69) TABLE-US-00008 TABLE 8 Characteristics of the oil (Sample A) used in performance tests I and II. A Properties Density to 25 C. and 585 mm Hg 0.852 Composition (% w) Crystallizable paraffins 6.13 Saturated hydrocarbon fraction 54.80 Aromatic hydrocarbon fraction 23.57 Polar hydrocarbon fraction (resins) 21.21 Asphaltenes 0.41

(70) The test results are shown in Table 9

(71) TABLE-US-00009 TABLE 9 Test results Mass deposited Efficiency, Product (mg) (%) Oil crude 758.2 0 1 10.3 98.6 Commercial 1 68.2 95.0 (Polyalkenyl succinimides)

II) Measurement Test Asphaltenes Dispersed in Heptane-Crude Oil Through UV-Visible Spectroscopy. Measuring the Dispersion of Asphaltenes in Crude Oil-Heptane Mixtures

(72) The test is based in the fact that asphaltenes are soluble in aromatic hydrocarbons, but insoluble in aliphatic hydrocarbons such as n-heptane. The dispersing capacity of a compound can be evaluated dissolving a small amount of crude oil in aromatic solvent and then adding the aliphatic hydrocarbon to provoke asphaltene precipitation. Given that asphaltenes absorb energy at UV-Visible region of electromagnetic spectrum, it is possible to have a proportional estimation of the amount of precipitated asphaltene by measuring the absorbance of an aliquot of the resulting supernatant liquid at a suitable wavelength within the UV-Visible region. Variants of this methodology have been used to determine the remnant concentration of asphaltene in solution, as a measure of the dispersing efficiency of chemical additives. Among the more representative documents are U.S. Pat. No. 6,313,367 and U.S. Patent Publication No. 2004/0039125.

(73) During the development of the present invention it was determine that the optimum wavelength to quantify the asphaltene dispersion is 510 nm.

(74) The procedure that has been design for this test consists of:

(75) Preparing a concentrate solution of 10,000 ppm of additive in toluene. Then 9.5 ml of n-heptane and 0.5 ml of concentrated additive to reach additive concentration of 100, 250, 1000 and 500 (mg/L) were added to a test tube, and then the mixture was vigorously agitated for 30 seconds and leave in repose for 24 hours. Afterwards a heptane reference was prepare, 9.5 ml of n-heptane and 0.5 ml of toluene were added to a test tube, immediately afterwards 0.1 ml of light crude oil or 0.1 ml of a 15% solution of heavy crude oil in toluene were also added, then the test tube was vigorously agitated for 30 seconds and leave in repose for 24 hours.

(76) After rest time, take 3 mL of the supernatant of the dispersion, taking care not to disturb the sediment, filter through a 0.45 mm syringe and transfer to the cell of UV-Visible spectrophotometer.

(77) Measuring the maximum absorbance wavelength of 510 nm selected. Calculate the scattering efficiency using the following equation to establish the efficiency percentage of dispersant:

(78) $\%\mathrm{Efficiency}=\frac{\mathrm{Test}\mathrm{tube}\mathrm{absorbance}-\mathrm{Reference}\mathrm{absorbance}}{\mathrm{Reference}\mathrm{absorbance}}100$

(79) The test results are shown in Table 10.

(80) TABLE-US-00010 TABLE 10 Test Results of dispersant efficiency determination through UV-Visible spectroscopy, samples of crude oil A. Dosage Absorbance Efficiency, Product (ppm) (U.A.) (%) White 0.4025 1 100 0.7745 92 250 0.7824 94 500 0.7964 98 2 500 0.6528 62 Commercial 1 500 0.7256 91 (Polyalkenyl succinimides)

(81) Table 10 shows the comparison between the efficiencies for Product 1 and the commercial Product 1 (derived from polyalkenyl succinimide), it is important to mention that the Product 1, the object of this invention, and present a good efficiency (98.6%). On the electrodeposition test and 98% in testing the dispersion of organic compounds by UV oil has the technical advantage of running as well as a corrosion inhibitor, which was confirmed in the evaluation tests-1D-182 NACE, NACE-0172 and linearly polarized electrochemical technique earlier in the present invention.