阅读说明：本技术 高分子量芳族多元醇聚酯的组合物与合成 (Composition and synthesis of high molecular weight aromatic polyol polyesters ) 是由 T·V·阿朗索 C·M·艾尔斯 S·M·霍伊尔斯 于 2018-11-13 设计创作，主要内容包括：本发明提供聚酯脱乳剂和合成所述聚酯脱乳剂的方法,所述方法包含使多元醇和芳族二酸的混合物反应的步骤,所述芳族二酸在反应过程期间无需升华或降解而溶解于所述多元醇中。(The present invention provides polyester demulsifiers and methods of synthesizing the same, comprising the step of reacting a mixture of a polyol and an aromatic diacid that dissolves in the polyol without sublimation or degradation during the reaction process.)

1. A method of synthesizing a polyester demulsifier, the method comprising the steps of:

reacting a mixture of a polyol and an aromatic diacid;

wherein the aromatic diacid is dissolved in the polyol during the course of the reaction without sublimation or degradation.

2. The method of claim 1, wherein the polyol is a polyalkylene glycol.

3. The method of claim 2, wherein the wt.% of EO of the polyalkylene glycol is between 5 wt.% and 100 wt.% of the functional group, and the corresponding wt.% of PO of the polyalkylene glycol is 95 wt.% to 0 wt.% of the functional group.

4. The method of claim 1, wherein the step of reacting a mixture of a polyol and an aromatic diacid further comprises reacting the mixture with a catalyst.

5. The method of claim 4, wherein the catalyst is selected from the group consisting of: titanium acetylacetonate and butylstannoic acid.

6. The method of claim 2, wherein the polyalkylene glycol has a molecular weight of about 200 to 10,000 g/mol.

7. The method of claim 1, wherein the aromatic diacid is selected from the group consisting of: phthalic acid, isophthalic acid, terephthalic acid, diphenyldicarboxylic acid and 2, 6-naphthalenedicarboxylic acid.

8. The method of claim 2, wherein the aromatic diacid is isophthalic acid.

9. The method of claim 7, wherein the polyalkylene glycol and the isophthalic acid are reacted at a stoichiometric ratio of 2 moles of the polyalkylene glycol to 1 mole of the isophthalic acid.

10. The method of claim 7, wherein the polyalkylene glycol and the isophthalic acid are reacted at a stoichiometric ratio of 5 moles of the polyalkylene glycol to 1 mole of the isophthalic acid.

11. The method according to claim 1 or 4, further comprising the step of:

purging the mixture with a gaseous nitrogen bath;

heating the mixture to 120 ℃ for 60 minutes;

obtaining an acid value of the mixture;

heating the mixture to 235 ℃;

monitoring the acid number of the mixture; and

once the acid number of the mixture has decreased by about 89% to 97%, preferably about 94% to 97%, the mixture is removed from the heat.

12. A polyester demulsifier having the formula:

wherein R is₁Is EO, PO or mixtures thereof; r₂PO, EO or mixtures thereof; r₃Is a polyol having (x +1) functional groups; r₄Is an aromatic hydrocarbon; m is more than or equal to 1; n is more than or equal to 0; x is more than or equal to 0; and y is more than or equal to 1.

13. The polyester demulsifier of claim 12 wherein the polyester demulsifier has the formula:

wherein R is₁Is EO, PO or mixtures thereof; r₂PO, EO or mixtures thereof; m is more than or equal to 1; and n is not less than 0.

14. The polyester demulsifier of claim 13 wherein:

R₁is EO;

R₂is PO; and is

Wherein: the wt.% of EO of the polyalkylene glycol is between 5 wt.% and 100 wt.% of the functional group and the corresponding wt.% of PO of the polyalkylene glycol is 95 wt.% to 0 wt.% of the functional group.

15. The polyester demulsifier of claim 13 wherein the molecular weight of the demulsifier is between about 200g/mol to about 100,000 g/mol.

Technical Field

The present invention generally relates to the synthesis of demulsifiers for aromatic polyol polyesters. More particularly, the present invention relates to a method for synthesizing an aromatic polyol polyester demulsifier by reacting a high molecular weight, low hydroxyl number polyol with an acid source dissolved in the polyol without sublimation or degradation during the reaction process. Because the process minimizes sublimation or degradation of the polyol, the yield of aromatic polyol polyester demulsifier from the reaction is preferably greater than 80%, more preferably greater than 90%, and most preferably greater than 95%.

Background

Demulsifiers or emulsion breakers are a class of chemicals used to separate emulsions, such as water from oil. Demulsifiers are commonly used in the processing of crude oils, which are typically produced with large amounts of brine. The water (and salts) must be removed from the crude oil prior to refining. Without removing most of the water and salt, serious corrosion problems may occur during the refining process.

In crude oil applications, a demulsifier is added to the oil/water emulsion and moves to the oil/water interface where it breaks or weakens the rigid membrane and enhances coalescence of water droplets. Optimal emulsion breaking using demulsifiers requires the proper selection of the chemical for a given emulsion, a sufficient amount of the chemical, thorough mixing of the chemical in the emulsion, and a residence time in the separator sufficient to settle the water droplets. Additional steps may include adding heat, a power grid, and/or coalescing agents to facilitate or completely break down the emulsion.

Methods of de-emulsifying are known in the art. For example, WO 2006068702 a2 discloses a crude oil treatment method using a demulsifier synthesized by polycondensing poly (tetrahydrofuran) and polyalkylene glycol using adipic acid and p-toluenesulfonic acid as catalysts. The reaction was continuously purged with nitrogen at a temperature of about 170 ℃. The performance of the de-emulsification was evaluated by the jar test method and showed superior performance compared to the existing commercial products. Specifically, the disclosed demulsifier samples were found to have a sample grind residual emulsion value between 1.9-4.0 and a free water value of 5.0-36.0. The sample was also found to have a water drop value of 40ml over a period of 60 minutes.

In addition, the synthesis of aromatic polyol polyesters is known in the art. U.S. published patent application No. 2004/0059011a1 and U.S. patent No. 5,360,900 disclose a method of synthesizing an aromatic polyol polyester by a polyol precursor, which is divided into two steps. In the first step, the components are heated to a temperature of about 190 ℃. Heating was then stopped, at which time a minimum amount of water purification was observed. In the second step, vacuum is applied for 2 to 5 hours to remove all residual water from the system, which in turn increases the conversion of the reaction. Finally, a catalyst is added to the reaction to avoid hydrolysis.

US2013/0184366 a1 also discloses an alternative method of synthesizing aromatic polyol polyesters by utilizing a continuous flow of nitrogen without the need for vacuum. The nitrogen bath removes distillable by-products from the mixture, but it can also result in the loss of low molecular weight glycols such as MEG and DEG. The conversion was monitored during the reaction, mainly by sampling the reaction product and measuring the acid number. The acidic groups are continuously consumed during the reaction to form ester groups and low acidity is sought to improve the stability of the synthesized product over a longer period of time.

Despite the variety of methods for synthesizing demulsifiers in the art, there remains a need to synthesize demulsifiers that are less costly than known demulsifiers, yet provide excellent water droplet performance and minimize residual (or undecomposed) emulsion. Furthermore, there is a need for a method of synthesizing an aromatic polyol polyester demulsifier that does not result in sublimation or degradation of the reactants during the course of the reaction, particularly when the reaction is carried out at elevated temperatures.

Disclosure of Invention

The present invention discloses the synthesis of novel aromatic polyol polyester demulsifiers by the polycondensation reaction of an acid source such as an aromatic diacid with a pre-existing polyol block copolymer demulsifier. In certain preferred processes, a catalyst may also be used. Because the process minimizes sublimation or degradation of the polyol, the yield of demulsifier from the reaction is preferably greater than 80%, more preferably greater than 90%, and most preferably greater than 95%.

A key feature of the process of the present invention is the discovery that the synthetic aromatic polyol polyester demulsifier exhibits enhanced crude oil demulsification performance when compared to the original polyethylene glycol from which it was synthesized. For example, it was determined that the claimed demulsifiers at concentrations of 300ppm and 400ppm each had a sampled milled residual emulsion value of about 0, and free water values of 6 and 4, which is superior to the methods known in the prior art. Furthermore, the sample was found to have a water drop value of 50ml over a period of 60 minutes, which is also superior to the methods known in the prior art. Aromatic polyol polyesters are also low cost.

Additionally, unlike processes known in the art, it has been found possible to make low hydroxyl number, high molecular weight polyols (e.g., DEMTRO L)^TMA series of demulsifiers) with a suitable aromatic diacid that is soluble in the polyol to synthesize an aromatic polyol polyester demulsifier such that minimal or no sublimation or degradation occurs during the course of the reaction. These results were observed even when the reaction was carried out at high temperature.

One preferred method of synthesizing the demulsifier of the present invention involves reacting an excess mole of polyethylene glycol relative to the aromatic diacid, most preferably 5 moles of polyethylene glycol relative to 1 mole of aromatic diacid. Preferred acidic components are carboxylic acids and carboxylic acid anhydrides, including phthalic anhydride, terephthalic acid and isophthalic acid, most preferably isophthalic acid. Metal-based catalysts may also be utilized, preferably catalysts such as titanium acetylacetonate (tradename Tyzor AA105) and butyl stannoic acid (tradename FASCAT 9100).

The kinetics of the disclosed reaction were evaluated by taking a sample from the reaction environment and measuring the acidity as a function of time by titration. As the reaction proceeds, the acid group reacts with the hydroxyl group and an ester bond is formed. As the acid groups are consumed, the reaction proceeds and acidity decreases at an exponential rate.

The process of the invention leads to the synthesis of demulsifiers which combine the characteristics of alkoxylated polymers with aromaticity, branching and high molecular weight distribution, which produce superior water droplet properties and minimize residual (or non-decomposed) emulsion compared to known demulsifiers.

Drawings

FIG. 1 depicts the synthesis reaction of the novel demulsifiers disclosed;

FIG. 2 depicts an apparatus for producing the novel demulsifiers disclosed; and

fig. 3 is a graph depicting water droplets over time for the novel demulsifier disclosed in comparison to the DEMTRO L1040 demulsifier.

Detailed Description

A method for synthesizing demulsifiers by reacting a high molecular weight, low hydroxyl number polyol with an aromatic diacid, wherein the aromatic diacid can be dissolved in the polyol during the course of the reaction without sublimation or degradation, even if the reaction is carried out at high temperatures (e.g., between 200 ℃ and 270 ℃). The process may also incorporate a catalyst. Because the process minimizes sublimation or degradation of the polyol, the yield of demulsifier from the reaction is preferably greater than 80%, more preferably greater than 90%, and most preferably greater than 95%.

Polyhydric alcohols

The first component of the reaction, polyol, is a polymer having a plurality of hydroxyl functional groups available for organic reactions. Monomeric polyols (such as glycerol, pentaerythritol, ethylene glycol and sucrose) are commonly used as starting points for polymeric polyols. These materials are typically reacted with propylene oxide or ethylene oxide to produce polymeric polyols.

The polymeric polyol is typically a polyether or polyester. Polyether polyols are prepared by reacting an epoxide such as ethylene oxide or propylene oxide with a multifunctional initiator in the presence of a catalyst, often a strong base such as potassium hydroxide or a double metal cyanide catalyst such as zinc hexacyanocobaltate-t-butanol complex. In contrast, polyesters are formed by condensation or step-growth polymerization of diols and dicarboxylic acids (or derivatives thereof), for example by reaction of diethylene glycol with phthalic acid.

One subclass of polyethers is known as polyglycols. The polyglycols are polyether diols and include polyethylene glycol, polypropylene glycol, poly (tetramethylene ether) glycol, and polyalkylene glycol. Of these, polyalkylene glycol (PAG) is used for the requirementsThe protected inventive polyols are preferred because they are inexpensive and have multiple functional groups that promote crosslinking. PAG is usually prepared by reacting, for example, glycerol, monopropylene glycol, and monoethylene glycol or a compound of the formula R (OH)₂With ethylene oxide and/or propylene oxide. Butylene oxide may also be incorporated, as well as a catalyst.

An exemplary chemical structure of a PAG is shown below:

wherein R is₁Is an Ethylene Oxide (EO) group having the formula:

R₂is a Propylene Oxide (PO) group having the formula:

m is the amount of EO and n is the amount of PO. As indicated above, the exemplary PAG has three functional groups.

Since the amount of EO and PO can vary in PAG synthesis reactions, the structure of the synthesized PAG product also varies. Common variations of PAGs include homopolymers of EO, homopolymers of PO, block copolymers of EO/PO, and reverse block copolymers of EO/PO. The PAG may also be linear or branched. The branching can be created by using polyglycols initiated by sorbitol, sucrose and other initiators with high hydroxyl functionality. Given these varying structures, PAGs can be designed for a wide range of molecular weights, viscosities, and functional properties.

For the disclosed invention, the preferred wt.% of EO is between 5 wt.% and 100 wt.% of the functional group, and the corresponding wt.% of PO is between 95 wt.% and 0 wt.% of the functional group. More preferably, the wt.% of EO is between 10 wt.% and 90 wt.% of the functional group, and the corresponding wt.% of PO is between 90 wt.% and 10 wt.% of the functional group. Finally, the wt.% of EO is between 20 wt.% and 80 wt.% of the functional group, and the corresponding wt.% of PO is between 80 wt.% and 20 wt.% of the functional group. The molecular weight of the PAG should be in the range of 200g/mol to 10,000g/mol, preferably about 1,000g/mol to 5,000g/mol, and most preferably 1,500g/mol to 2,500 g/mol.

In addition to PAGs, other polymeric polyols that produce polyethers having 2, 3, or more functional groups can also be used in the synthesis of the novel demulsifiers disclosed.

Aromatic diacids

The aromatic diacid includes two acidic functional groups and at least one aromatic hydrocarbon. It has been determined that aromatic diacids suitable for use in the claimed invention should contain at least 2 carboxylic acid or organic anhydride groups attached to at least one benzene ring. In addition, aromatic carboxylic acids having a functionality greater than or equal to 3 functional groups are preferred.

One class of diacids that meets these requirements is known as aromatic dicarboxylic acids. Members of this class include phthalic acid, isophthalic acid, terephthalic acid, diphenyldicarboxylic acid, and 2, 6-naphthalenedicarboxylic acid. Of these, isophthalic acid is the preferred aromatic diacid of the disclosed invention because it exhibits excellent solubility through polyalkylene glycol dissolution and faster kinetics for esterification. The chemical structure of isophthalic acid is as follows:

catalyst and process for preparing same

As noted above, the disclosed invention may also include a catalyst. The catalyst accelerates the reaction rate of the chemical reaction by changing the reaction mechanism. Typically, the catalyst is regenerable and/or is not itself affected by the reaction. It was determined that metal-based catalysts were most effective in the disclosed invention, with titanium acetylacetonate (trade name) being preferredAA105), and butylstannoic acid (trade name)9100) And most preferably9100。AA105 has the following chemical structure:

while9100 has the following chemical structure:

synthesis of demulsifiers

Demulsifiers are typically synthesized from the reaction of acid-catalyzed phenolic resins, base-catalyzed phenolic resins, epoxy resins, polyethyleneimines, polyamines, diepoxides, polyols, and/or dendrimers. Demulsifiers are typically formulated with polymeric chains of ethylene oxide and polypropylene oxides of alcohols, ethoxylated phenols, ethoxylated alcohols and amines, ethoxylated resins, ethoxylated nonylphenols, polyols and sulfonates. In particular, the addition of ethylene oxide increases water solubility, while the addition of propylene oxide decreases water solubility.

Factors that affect the performance of demulsifiers in crude oils include temperature, pH/acidity, the type of crude oil being demulsified, the composition of the brine/brine, and the size and distribution of the droplets. The increase in temperature leads to a decrease in emulsion stability and therefore requires lower doses of demulsifier. The pH also affects the performance of the demulsifier. Typically, a basic pH will promote an oil-in-water emulsion, while an acidic pH will produce a water-in-oil emulsion. Thus, a higher pH helps to destabilize the water-in-oil emulsion.

The required hold between PAG and isophthalic acid is depicted in FIG. 1Examples of reaction schemes wherein R₁Is EO, R₂Is PO, m is the amount of EO, and n is the amount of PO. The preferred stoichiometric ratio for this reaction is 2 moles of polyalkylene glycol to 1 mole of isophthalic acid. However, it was found that the most preferred ratio for the optimum dissolution of isophthalic acid with polyalkylene glycol is 5 moles of polyalkylene glycol to 1 mole of isophthalic acid. Depending on the composition of the PAG precursor, the resulting demulsifier can have EO/PO blocks, including homopolymers of EO, homopolymers of PO, block copolymers of EO/PO, reverse block copolymers of EO/PO, or mixtures of block types. The EO/PO blocks of the demulsifier may also be linear or branched, and are preferably branched. The molecular weight of the resulting demulsifier is in the range of from about 200g/mol to about 100,000 g/mol.

In addition, and as described above, the reagents used in the aromatic polyol polyester reaction may be polymeric polyols other than PAGs and aromatic diacids other than isophthalic acid. The general chemical formula of the demulsifier for aromatic polyol polyesters synthesized by this reaction is as follows:

wherein R is₁Is EO, PO or mixtures thereof; r₂PO, EO or mixtures thereof; r₃Is a polyol having (x +1) functional groups; r₄Is an aromatic hydrocarbon; m is more than or equal to 1; n is more than or equal to 0; x is more than or equal to 0; and y is more than or equal to 1.

A reaction system for producing an exemplary aromatic polyol polyester demulsifier is depicted in fig. 2. In the first step, isophthalic acid and PAG are loaded together into reactor 5 and heated to about 100 deg.C to 150 deg.C, preferably about 120 deg.C. The temperature in the reactor 5 is controlled by a temperature controller 11. In addition, the over-temperature controller 16 may be used to provide redundancy in the event of a failure of the temperature controller 11. While heating, isophthalic acid and PAG are stirred in reactor 5 by mixer 4. Once the desired temperature is reached in reactor 5, the catalyst (preferably) is addedAA105 or9100) Added to reactor 5 and stirred further through mixer 4. The concentration of the catalyst is preferably about 0.01 wt.% to 0.1 wt.%, more preferably 0.03 wt.% of the initial mixture of isophthalic acid and PAG.

After the addition of the catalyst is complete, the mixture is maintained at about 100 ℃ to 150 ℃, preferably about 120 ℃, and stirred for about 45 to 75 minutes, preferably about 60 minutes, to allow the components to be fully miscible. Once completed, the temperature in reactor 5 is raised to about 200 ℃ to 235 ℃, preferably about 235 ℃. The progress of the reaction was monitored by measuring the acid value by an autotitrator. When the conversion of the limiting reactant (i.e., aromatic diacid) is greater than about 90%, preferably greater than about 95%, the reaction is considered complete, resulting in a reduction in acid number (mg KOH/g) of greater than about 89%, preferably greater than about 94%.

During the course of the reaction, the water which is discharged is purged from the system by means of nitrogen supplied from a nitrogen source 17, which flows over the reactor 5 and a nitrogen source 18 bubbled into the reactor 5, the flow of which is controlled by a pressure regulator 1. The waste nitrogen is then transferred to a condenser 13 which is cooled by a cooler 12 and the effluent water and/or contaminants are collected in a purge collector vessel 14. By monitoring N₂The bubbler 15 confirms the continuous flow of nitrogen.

Application method

After the reaction is completed, the demulsifier may be used as a crude oil emulsion decomposer. In one embodiment of the claimed method, crude oil is extracted from a well and transferred to a dewatering facility. Depending on the extraction method (e.g. water flooding), the crude oil may be mixed with brine. Alternatively, the crude oil may naturally contain water. In either case, the water must be removed from the crude before further processing can take place.

As the crude oil progresses through the dewatering equipment, it is exposed to an aromatic polyol polyester demulsifier, preferably in a dissolved state and preferably at elevated temperatures. The amount of demulsifier used is from 0.0001% to 5% (1-50,000ppm), preferably from 0.0005% to 2% (5-20,000ppm), more preferably from 0.0008% to 1% (8-10,000ppm), and most preferably from 0.001 to 0.1 wt.% polymer (10-1000ppm), depending on the oil fraction of the emulsion used. Once the de-emulsification is complete, the separated dry oil is removed from the dewatering equipment and can be passed on for further refining.

The efficacy of the demulsifier can be determined by exposing a crude oil sample to the demulsifier in a reaction chamber such as a demulsified glass. After about 60 minutes, the treated crude oil will separate into a bottom water layer, an intermediate emulsion layer (i.e., oil/water interface), and a top oil layer. A sample of the emulsion layer (referred to as a "sample fraction") is removed, placed in a centrifuge tube (preferably an ASTM approved conical centrifuge tube) and treated with a starting solvent such as kerosene. After shaking the tube to evenly distribute the starting solvent, the tube was centrifuged for about 10 minutes. Once centrifugation is complete, the separated water is removed and measured (hereinafter referred to as "free water", "W", or "water 1"). Once this was done, a drop of drops (Tetrolite F46) was added to the remaining emulsion and the emulsion was centrifuged a second time. After the second centrifugation is completed, the volume of water separated for the second time (hereinafter referred to as "water 2") is removed.

Using the "water 1" and "water 2" measurements, the bottom sediment (B.S.), i.e., the undecomposed emulsion, was calculated according to the following equation:

b.s. ═ (water 2-water 1) x2

In addition to the "sampled fraction", the efficacy of the demulsifier can also be measured by obtaining a "complex fraction" which can be obtained by treating the crude oil again with the demulsifier for 60 minutes and then manually removing all of the separated water from the demulsified glass article. Samples of the crude oil were then removed and centrifuged according to the same procedure as the fractions sampled, to obtain b.s. and W measurements.

By measuring crude oil treated with the claimed demulsifier, it was determined that the claimed demulsifier provided excellent water droplet performance and minimized residual (or undecomposed) emulsion.

Working examples

The following examples illustrate various representative attributes of the invention, but are in no way to be construed as limiting.

875.12 grams of a polyalkylene glycol EO/PO copolymer (with 40% by weight EO in the composition, tradename DEMTRO L) was used^TM1040) 11.64 g of isophthalic acid and 0.27 g ofAA105 to prepare high molecular weight aromatic polyol polyesters. Mixing the acid and the polyalkylene glycol together at room temperature and carrying out N₂Bubbling was performed to remove all air in the reaction flask. The temperature was increased to 120 ℃ and the catalyst was added to the reactor using a funnel. After addition of the catalyst, N is increased₂Flowing to avoid further oxidation. After 30 minutes of homogenization, the temperature was set to 235 ℃. When the temperature reached the desired level, some water was observed at the condenser. When the temperature was stabilized at 235 ℃, 5ml samples were collected per hour. After cooling the sample, acid number measurements were made according to DOWM 100387-TE 95A. It is desirable to reduce the initial acidity by about 95% to achieve the desired conversion.

The reaction was monitored by acid number titration. The observed results are detailed in table I below.

TABLE I

The acidity decreased by 96.3%, indicating the optimum conversion of isophthalic acid (limiting reagent).

The resulting material can be finally characterized using Gel Permeation Chromatography (GPC) in combination with Ultraviolet (UV), Refractive Index (RI) detectors and fourier transform infrared spectroscopy (FTIR). The distribution of molecular weights shows the 3 peaks formed. The first and highest molecular weight peaks show a composition of 5.3% of the final product, with Mn equal to 15334Da and Mw equal to 15830 Da. The second peak was determined to be 23.6% of the final composition, with Mn equal to 9092Da and Mw equal to 9284 Da. The last peak of low molecular weight is unreacted polyethylene glycol, having a final composition of 71.1%, with Mn equal to 3767Da and Mw equal to 4314 Da. Because the polyethylene glycol is in excess in this system, it produces a system with 30% polyol polyester and 70% unreacted polyethylene glycol in the final mixture. The inclusion of isophthalic acid in the polymeric backbone can be identified by using UV absorption at 240 nm.

The efficacy of the aromatic polyol polyester was determined by measuring the amount of water separated from the crude oil emulsion and the amount of oil discharged over time to this end, 100m L crude oil emulsion was filled into de-emulsified glass articles (conical, graduated glass bottles), the water content of the emulsion was 50%, in each glass article a defined amount of de-emulsifying agent was added slightly below the surface of the oil emulsion with a micropipette, the de-emulsifying agent was mixed into the emulsion by vigorous shaking after which the de-emulsified glass articles were placed in a bath at a moderate temperature of 80 ℃ and the water separation was observed.

After 60 minutes of emulsion decomposition, a sample of oil (sample fraction) was taken from the oil/water interface of the de-emulsified glass article and the water content was determined according to ASTM D96. First, the samples were diluted in kerosene and centrifuged for 10 minutes using an approved ASTM conical centrifuge tube. After centrifugation is complete, the volume of separated water is removed and the free water or "water 1" is measured. Next, a drop of drops (Tetrolite F46) was added and the sample was centrifuged for 10 minutes, after which the separated water volume was removed and "water 2" was measured.

Bottom sediment (B.S.) was calculated according to the following equation:

b.s. ═ (water 2-water 1) x2

Separately, a sample of de-emulsifiable concentrate was also obtained and centrifuged, in which the water was first manually drained (complex fraction). B.s. and W values were also obtained from these samples.

The novel demulsifiers from aromatic polyol polyester at doses ranging from 100ppm to 400ppm (hereinafter referred to as "DEMTRO L1040 polyester 1040") were compared to a standard demulsifier at the same dose (DEMTRO L1040 in this example) the water droplets of each demulsifier were measured as a function of time and are depicted in Table II and FIG. 3.

TABLE II

In addition, BS and W values for various demulsifiers sampled and co-milled were measured and are described in table III.

TABLE III

As shown in the above tables and figures, with conventional DEMTRO L^TM1040 compared to the novel demulsifier (DEMTRO L)^TM1040) showed faster water dripping in all doses evaluated. The residual emulsion of the novel demulsifier was almost zero at 300ppm and 400ppm and the level of free water present after the treatment was also minimized, compared to the conventional art.

Although the present invention has been described with reference to the preferred embodiments disclosed in the above description and drawings, further embodiments of the invention are possible without departing from the invention. Accordingly, the scope of the invention should be limited only by the attached claims.