Method for determining HLB value of asphaltene based on asphaltene structure

Abstract

The invention provides a method for determining an asphaltene HLB (hydrophile-lipophile balance) value based on an asphaltene structure. The method comprises the following steps: step 1, defining a relative ratio R of integral curve areas of hydrophilic protons; 2, further calculating an asphaltene HLB value based on the R value; 3, calculating an average structure parameter of the asphaltene sample by using an improved BL method; 4, performing single-factor fitting on the basis of the asphaltene HLB value and the selected related parameters; 5, further multi-factor fitting is carried out, and a linear formula for asphaltene HLB value calculation is obtained; and step 6, comparing a calculation result of the fitting formula with a nuclear magnetic method result, and finally determining an asphaltene HLB value calculation formula. According to the method, the calculation formula of the HLB value of the asphaltene is fitted based on the nuclear magnetic hydrogen spectrogram and the average structure parameter of the asphaltene, so that the effect of preliminarily screening the surfactant is achieved, and the time cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of petrochemical engineering, and particularly to a method for determining the HLB value of asphaltene based on the asphaltene structure. Background Art

[0002] As the most polar component in crude oil, asphaltene has certain surface activity, which can promote the formation of emulsions in the oil-water mixed system and affect the oil recovery rate of oilfields. In addition, during enhanced oil recovery, adding surfactants for oil displacement to improve the oil production efficiency of crude oil is currently the most economical and effective method. During this process, asphaltene in crude oil also has certain surface activity. Therefore, the presence and role of asphaltene often affect the action of surfactants, thereby changing the action effect of surfactants. Therefore, during enhanced oil recovery, it is often necessary to investigate the surface activity of asphaltene. When selecting a suitable surfactant, the most important parameter is the Hydrophile-Lipophile Balance (HLB value) of the surfactant. The HLB value is a powerful basis for judging the hydrophilic and lipophilic abilities of surfactants, determining the uses of surfactants, and selecting surfactants.

[0003] For a compound surfactant system, its HLB value can be calculated from the HLB values of the components of the compound system. Therefore, by measuring or calculating the HLB value of asphaltene, the HLB value under the combined action of asphaltene and added surfactants can be predicted, thus more effectively screening surfactants.

[0004] Common HLB value determination methods mainly include the conventional emulsification method, viscosity method, fluorescence method, water number method, and nuclear magnetic resonance hydrogen spectroscopy method. Among them, nuclear magnetic resonance hydrogen spectroscopy determines the chemical shifts of the protons in the lipophilic group and the hydrophilic group in the surfactant, respectively calculates the integral curve areas of the hydrophilic protons in the hydrophilic group and the lipophilic protons in the lipophilic group, then calculates the relative ratio R of the integral curve area of the hydrophilic protons, and finally calculates the HLB value after mixing two types of surfactants by the mass fraction summation method. As a natural surfactant, asphaltene has a complex and diverse structure, and its HLB value is not easily obtained.

[0005] In the Chinese patent application with the application number CN201010240645.4, it involves an asphalt emulsifier for anionic emulsified asphalt cement mortar, which contains sodium lignosulfonate, a non-ionic surfactant, and water; among them, the number-average molecular weight of the non-ionic surfactant is 600 - 5800; the content of sodium lignosulfonate is 10 - 50% by mass, the content of the non-ionic surfactant is 5 - 40% by mass, and the content of water is 10 - 85% by mass. The asphalt emulsifier for CRTS I type anionic emulsified asphalt cement mortar of this invention has a moderate HLB value, a slow demulsification rate, a moderate foaming ability, and a strong foam stability ability.

[0006] In the literature "Determination of the HLB Values of JY-2 Type and JY-3 Type Cationic Asphalt Emulsifiers" (Fujian Chemical Industry, 2005.3), it involves using rapeseed oil, Span-60, Tween-60, etc. as reagents, and conducting an emulsification experiment by the trial-and-error method under a constant temperature water bath at 35°C. The measured HLB values of JY-2 type and JY-3 type cationic asphalt emulsifiers are 10.13 and 12.11 respectively.

[0007] In the literature "Analysis, Determination and Calculation of the HLB Values of Surfactants" (Fine Petrochemical Industry, 2001.3), various analysis and testing methods of the HLB values of surfactants and relevant calculation formulas are introduced, including the emulsification method, cloud point method, water number method, critical micelle concentration method, distribution coefficient method, solubility method, heat of hydration method, nuclear magnetic resonance method, chromatography method, and the applicability of each method is analyzed.

[0008] The above existing technologies all have great differences from this invention and cannot solve the technical problems we want to solve. Therefore, we have invented a new method for determining the HLB value of asphaltene based on the asphaltene structure. Summary of the Invention

[0009] The purpose of this invention is to provide a method for determining the HLB value of asphaltene based on the asphaltene's nuclear magnetic resonance hydrogen spectrum and average structure parameters to fit the calculation formula of the HLB value of asphaltene, so as to achieve the effect of preliminarily screening surfactants and reducing the time cost.

[0010] The purpose of this invention can be achieved by the following technical measures: A method for determining the HLB value of asphaltene based on the asphaltene structure, which includes:

[0011] Step 1, define the relative ratio R of the area of the hydrophilic proton integration curve;

[0012] Step 2, further calculate the HLB value of asphaltene based on the R value;

[0013] Step 3, use the improved BL method to calculate the average structure parameters of the asphaltene sample;

[0014] Step 4: Perform single-factor fitting based on the HLB value of asphaltene and the selected relevant parameters;

[0015] Step 5: Perform further multi-factor fitting to obtain a linear formula for calculating the HLB value of asphaltene;

[0016] Step 6: Compare the calculation results of the fitting formula with the results of the NMR method to finally determine the calculation formula for the HLB value of asphaltene.

[0017] The object of the present invention can also be achieved by the following technical measures:

[0018] The method for determining the HLB value of asphaltene based on the asphaltene structure further includes, before step 1, in order to eliminate the contingency of the results, selecting multiple experimental samples with different structures for experiments.

[0019] In step 1, according to the nuclear magnetic resonance hydrogen spectrum, taking 2.5 as the midline, find the relative integral curve area ∑H of the hydrophilic protons in the hydrophilic group (W) and the relative integral curve area ∑H of the lipophilic protons in the lipophilic group (O) , and then find the relative ratio of the integral curve area of the hydrophilic protons.

[0020] In step 1, the calculation formula is:

[0021] R = ∑H (W) / (∑H (W) + ∑H (O) ).

[0022] In step 2, further calculate the HLB value of asphaltene based on the R value calculated from the nuclear magnetic resonance hydrogen spectrum. The calculation formula is:

[0023] HLB = 60R / (R + 2).

[0024] In step 3, use the improved BL method to calculate the average structure parameters of the asphaltene sample as shown in Table 1

[0025] Table 1 Calculation formulas for each parameter of the improved B-L method

[0026]

[0027]

[0028] Among them,

[0029] C T represents the total number of carbons in the molecule;

[0030] C A represents the number of aromatic carbons in the molecule;

[0031] C N Represents the number of cycloalkane carbons in the molecule;

[0032] C p Represents the number of alkyl carbons in the molecule;

[0033] C α Represents the carbon at the α position;

[0034] C AP Represents the number of peripheral carbons of the aromatic ring system;

[0035] H AU / C A Condensation degree parameter of the aromatic ring system;

[0036] H T Represents the total number of hydrogen atoms in the average molecule;

[0037] H A Represents the hydrogen atoms directly connected to the aromatic carbon;

[0038] H α Represents the hydrogen atoms directly connected to the α carbon of the aromatic ring;

[0039] H β Represents the hydrogen on the β carbon of the aromatic ring and the CH 2 and the hydrogen on the CH group beyond β;

[0040] Hydrogen atoms;

[0041] H γ Represents the γ position of the aromatic ring and the hydrogen atoms on the CH 3 group beyond the γ position.

[0042] In step 4, use the following average structural parameters that are relatively easy to obtain and have a large correlation with the hydrophilic-lipophilic property of asphaltene as correlation parameters: aromatic carbon ratio f A That is, it reflects the number of aromatic rings, the peripheral hydrogen substitution rate σ of the aromatic ring system, the contents of heteroatoms N and O, which reflect the content of polar functional groups, and preliminarily explores the quantitative relationship between the hydrophilic-lipophilic property of asphaltene and its structure, in order to provide a reference for the exploration of subsequent HLB influencing factors and the research of surface activity.

[0043] In step 4, use the selected parameters as independent variables and the experimentally measured HLB values as dependent variables for data processing. Use the method of scatter plot drawing to make a graph, and use the method of adding a trend line to the scatter plot obtained to get a correlation equation, that is, obtain the single-factor analysis result.

[0044] In step 5, through fitting the single factors, it is found that all the selected parameters are linearly correlated with the HLB value. Due to the complexity of the asphaltene structure, further multi-factor fitting is selected to obtain a linear formula for calculating the HLB value of asphaltene.

[0045] In step 5, the HLB value measured by nuclear magnetic method is used as the dependent variable, and four structural parameters, namely the O content f O , the S content f S , the aromatic carbon ratio f A , and the hydrogen substitution rate σ of the periphery of the aromatic ring system are used as independent variables for linear fitting. Since most methods for calculating the HLB value are linear, the formula type mainly selects linear attempts, and finally a fitting formula is obtained.

[0046] In step 5, the HLB value of asphaltene is further calculated based on the R value calculated from the nuclear magnetic resonance hydrogen spectrum. The calculation formula is:

[0047] HLB = 60R / (R + 2)

[0048] The fitting formula for determining the HLB value of asphaltene is:

[0049] HLB = 5.85f A - 2.44σ + 0.08f S + 0.03f O + 1.04.

[0050] The method for determining the HLB value of asphaltene based on the asphaltene structure in the present invention performs single-factor and multi-factor fittings based on the basic structural parameters of asphaltene, proposes a calculation formula for the HLB value of asphaltene, and compares it with the nuclear magnetic resonance hydrogen spectrum method. The verification results show that: this formula has high precision, can more accurately and quickly screen surfactants, and effectively reduce the time cost. Based on the existing analysis means, the present invention fits the calculation formula for the HLB value of asphaltene based on the nuclear magnetic resonance hydrogen spectrum diagram and average structural parameters of asphaltene to achieve the effect of preliminary screening of surfactants and reduce the time cost. To sum up, the beneficial effects of adopting the above fitting method are reflected in:

[0051] Since it is based on nuclear magnetic data and there are actual data comparisons, the accuracy is higher.

[0052] The selected samples have diversity, avoiding the contingency of experimental results.

[0053] This fitting formula can quickly calculate the HLB value of asphaltene, and preliminarily screen out surfactants with strong adaptability at a relatively fast speed, which can greatly reduce the time and economic costs. Description of the Drawings

[0054] Figure 1 It is the nuclear magnetic resonance hydrogen spectrum diagram of a certain oil sample ASP in a specific embodiment of the present invention;

[0055] Figure 2 It is the schematic diagram of the fitting curve of the aromatic carbon ratio f A and the HLB value in a specific embodiment of the present invention;

[0056] Figure 3 The fitting curve graph of the hydrogen substitution rate σ around the aromatic ring system and the HLB value in a specific embodiment of the present invention;

[0057] Figure 4 The fitting curve graph of the S element content and the HLB value in a specific embodiment of the present invention;

[0058] Figure 5 The fitting curve graph of the O element content and the HLB value in a specific embodiment of the present invention;

[0059] Figure 6 The comparison graph of the HLB fitting value and the actual value of asphaltene in a specific embodiment of the present invention;

[0060] Figure 7 The flow chart of a specific embodiment of the method for determining the HLB value of asphaltene based on the asphaltene structure of the present invention. Specific Embodiments

[0061] It should be noted that the following detailed description is exemplary and is intended to provide further illustration of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0062] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, and / or combinations thereof.

[0063] As Figure 7 shown, Figure 7 The flow chart of the method for determining the HLB value of asphaltene based on the asphaltene structure of the present invention. The method for determining the HLB value of asphaltene based on the asphaltene structure includes:

[0064] S101: In order to eliminate the contingency of the results, multiple experimental samples with different structures are selected for.

[0065] S102: Define the relative ratio R of the integral curve area of hydrophilic protons. According to the nuclear magnetic resonance hydrogen spectrum, taking 2.5 as the midline, find the relative integral curve area ∑H(W) of hydrophilic protons in hydrophilic groups and the relative integral curve area ∑H(O) of lipophilic protons in lipophilic groups, and then find the relative ratio of the integral curve area of hydrophilic protons. The calculation formula is:

[0066] R = ∑H (W) / (∑H(W) +∑H (O) )。

[0067] S103: Calculate the HLB value of asphaltene further based on the R value calculated from the nuclear magnetic resonance hydrogen spectrum. The calculation formula is:

[0068] HLB = 60R / (R + 2)

[0069] S104: Use the improved BL method to calculate the average structural parameters of the asphaltene sample.

[0070] S105: Conduct a single - factor fitting on the HLB value of asphaltene calculated by nuclear magnetic resonance and the selected relevant parameters.

[0071] S106: It is found through the fitting of single - factors that all the selected parameters are linearly correlated with the HLB value. Due to the complexity of the asphaltene structure, further multi - factor fitting is selected to obtain the linear formula for calculating the HLB value of asphaltene.

[0072] Among them, the specific method is to use the HLB value measured by the nuclear magnetic resonance method as the dependent variable, and four structural parameters (f O , f S represents the O and S contents; f A represents the aromatic carbon ratio, and σ represents the hydrogen substitution rate on the periphery of the aromatic ring system.) as the independent variables for linear fitting. Since most methods for calculating the HLB value are linear, the formula type mainly selects linear attempts. Finally, the fitting formula is obtained.

[0073] Calculate the HLB value of asphaltene further based on the R value calculated from the nuclear magnetic resonance hydrogen spectrum. The calculation formula is:

[0074] HLB = 60R / (R + 2).

[0075] Determine the fitting formula for the HLB value of asphaltene as:

[0076] HLB = 5.85f A - 2.44σ + 0.08f S + 0.03f O + 1.04

[0077] The following are several specific embodiments of applying the present invention

[0078] Embodiment 1

[0079] In a specific Embodiment 1 of applying the present invention, the method for determining the HLB value of asphaltene based on the asphaltene structure includes:

[0080] In step 1, according to the nuclear magnetic resonance hydrogen spectrum, with 2.5 as the mid - line, find out the relative integral curve area ∑H of the hydrophilic protons in the hydrophilic groups (W)The relative integral curve area ∑H of lipophilic protons in the lipophilic group (O) , and then the relative ratio R of the integral curve area of hydrophilic protons is obtained.

[0081] The formula for calculating the relative ratio R of the integral curve area of hydrophilic protons is:

[0082] R = ∑H (W) / (∑H (W) + ∑H (O) ).

[0083] In step 2, based on the R value calculated from the nuclear magnetic resonance hydrogen spectrum, the HLB value of asphaltene is further calculated. The calculation formula is:

[0084] HLB = 60R / (R + 2).

[0085] In step 3, the improved BL method is used to calculate the average structural parameters of the asphaltene sample, as shown in Table 1:

[0086] Table 1 Calculation formulas for each parameter of the improved B-L method

[0087]

[0088]

[0089] Among them,

[0090] C T represents the total number of carbon atoms in the molecule

[0091] C A represents the number of aromatic carbon atoms in the molecule

[0092] C N represents the number of naphthenic carbon atoms in the molecule

[0093] C p represents the number of alkyl carbon atoms in the molecule

[0094] C α represents αwei carbon

[0095] C AP represents the peripheral carbon atoms of the aromatic ring system

[0096] H AU / C A Aromatic ring system condensation degree parameter

[0097] H T represents the total number of hydrogen atoms in the average molecule

[0098] H A represents the hydrogen atoms directly connected to the aromatic carbon;

[0099] Hα represents a hydrogen atom directly connected to the α-carbon of an aromatic ring;

[0100] H β represents a hydrogen atom on the β-carbon of an aromatic ring and CH further away from the β-carbon 2 and on the

[0101] CH group;

[0102] H γ represents a hydrogen atom on the γ-position of an aromatic ring and on the CH 3 group further away from the γ-position. In step 4, the following average structural parameters, which are relatively easy to obtain and have a large correlation with the hydrophilic-lipophilic property of asphaltene, are used as correlation parameters: aromatic carbon ratio f A That is, it reflects the number of aromatic rings, the hydrogen substitution rate σ on the periphery of the aromatic ring system, the contents of heteroatoms N and O, which reflect the content of polar functional groups, and preliminarily explores the quantitative relationship between the hydrophilic-lipophilic property of asphaltene and its structure, in order to provide a reference for the exploration of subsequent HLB influencing factors and the research of surface activity.

[0103] Taking the selected parameters as independent variables and the experimentally measured HLB values as dependent variables for data processing, a scatter plot is made by the method of scatter plotting, and the correlation equation is obtained by adding a trend line to the scatter plot made, that is, the single-factor analysis result is obtained.

[0104] In step 5, it is found through fitting of single factors that all the selected parameters are linearly correlated with the HLB value. Due to the complexity of the asphaltene structure, further multi-factor fitting is selected, and the linear formula for calculating the HLB value of asphaltene is obtained as:

[0105] HLB = 5.85f A -2.44σ + 0.08f S + 0.03f O + 1.04

[0106] where: f O and f S represent the contents of O and S; f A represents the aromatic carbon ratio, and σ represents the hydrogen substitution rate on the periphery of the aromatic ring system.

[0107] Example 2

[0108] In a specific Example 2 of applying the present invention, taking a certain asphaltene sample as an example, the fitting formula is:

[0109] HLB = 5.85f A -2.44σ + 0.08f S + 0.03f O + 1.04

[0110] Step 1: Select multiple asphaltene samples and calculate the average structural parameters. The structure is shown in Table 2:

[0111] Table 2: Table of average structural parameters of samples

[0112] Asphaltene source <![CDATA[f A > σ <![CDATA[H AU / C A > <![CDATA[f N > <![CDATA[f P > <![CDATA[R A > <![CDATA[R N > <![CDATA[R T > <![CDATA[n C / n H > Oil sample No. 1 0.45 0.5 0.78 0.23 0.5 0.5 6.61 23.45 0.84 Oil sample No. 2 0.46 0.64 0.94 0.16 0.55 0.55 0.20 39.30 0.79 Oil sample No. 3 0.46 0.42 0.9 0.15 0.57 0.57 1.47 26.38 0.8 Oil sample No. 4 0.49 0.11 0.86 0.18 0.5 0.5 0 33.89 0.82 Oil sample No. 5 0.49 0.66 0.7 0.2 0.44 0.44 16.56 51.19 0.95 Oil sample No. 6 0.52 0.57 0.81 0.18 0.49 0.49 12.07 42.11 0.96 Oil sample No. 7 0.43 0.42 0.81 0.18 0.51 0.51 1.21 58.15 0.77 Oil sample No. 8 0.49 0.65 0.78 0.18 0.48 0.48 13.87 45.42 0.93 Oil sample No. 9 0.49 0.53 0.83 0.16 0.52 0.52 12.12 43.14 0.91 Oil sample No. 10 0.38 0.68 0.8 0.18 0.51 0.51 12.25 38.35 0.78 Oil sample No. 11 0.51 0.52 0.83 0.19 0.51 0.51 13.29 50.01 0.94 Oil sample No. 12 0.47 0.07 0.29 0.07 0.46 0.46 7.41 58.4 0.85 Oil sample No. 13 0.5 0.11 0.32 0.06 0.44 0.44 6.22 56.4 0.88 Oil sample No. 14 0.46 0.2 0.39 0.03 0.51 0.51 4.42 68.56 0.81 Oil sample No. 15 0.47 0.2 0.45 0 0.53 0.53 0.01 63.9 0.79 Oil sample No. 16 0.58 0.06 0.3 0.06 0.36 0.36 10.59 115 1 Oil sample No. 17 0.52 0.11 0.39 0 0.48 0.48 0.00 83.3 0.87 Oil sample No. 18 0.59 0.22 0.43 0.01 0.4 0.4 2.20 110 0.99

[0113] Step 2: Determine the elemental content of the asphaltene samples. The results are shown in Table 3:

[0114] Table 3: Table of elemental analysis of samples

[0115] Oil sample H / wt% C / wt% S / wt% N / wt% O / wt% <![CDATA[M / (g·mol -1 )]]> μ Oil sample No. 1 7.77 78.76 7.31 1.30 4.86 1835 12.6 Oil sample No. 2 8.81 83.86 2.55 1.84 2.94 3780 12.9 Oil sample No. 3 8.68 83.24 2.72 1.87 3.49 2461 11.9 Oil sample No. 4 8.53 84.01 1.27 1.95 4.24 3148 17.8 Oil sample No. 5 7.31 83.11 1.43 2.12 6.03 3156 20.8 Oil sample No. 6 7.24 83.31 1.57 2.04 5.84 2631 21.6 Oil sample No. 7 9.11 84.26 2.50 1.94 2.19 5777 22.1 Oil sample No. 8 7.54 83.80 1.75 2.11 4.8 2891 19.7 Oil sample No. 9 7.66 83.87 1.77 2.07 4.63 2843 18.9 Oil sample No. 10 9.02 84.19 2.5 1.96 2.33 3089 18.2 Oil sample No. 11 7.46 83.80 3.0 2.0 3.74 3232 19.5 Oil sample No. 12 8.05 81.35 2.00 1.31 7.29 4883 26.21 Oil sample No. 13 7.92 82.69 1.18 1.28 6.93 4488 24.99 Oil sample No. 14 8.71 84.37 0.67 1.78 4.47 6130 25.00 Oil sample No. 15 8.35 78.79 1.83 1.09 9.94 6387 37.29 Oil sample No. 16 6.98 83.56 6.18 0.74 2.54 7818 2.83 Oil sample No. 17 7.99 82.79 2.03 1.35 5.84 7143 31.66 Oil sample No. 18 6.79 79.84 6.52 0.71 6.14 8322 3.14

[0116] Step 3: Calculate the HLB value of asphaltene using nuclear magnetic resonance hydrogen spectroscopy:

[0117] According to Figure 1 the nuclear magnetic resonance hydrogen spectrum, with a chemical shift of 2.5 as the midline, find the relative integral curve area ∑H of the hydrophilic protons in the hydrophilic group (W) and the relative integral curve area ∑H of the lipophilic protons in the lipophilic group (O) , and then find the relative ratio R of the integral curve area of the hydrophilic protons,

[0118] R = ∑H (W) / (∑H (W) +∑H (O) ).

[0119] According to the formula calculate the HLB value of asphaltene to obtain the calculation formula of the HLB value by nuclear magnetic resonance method.

[0120] HLB = 60R / (R + 2)

[0121] Similarly, the HLB values of each asphaltene can be calculated as shown in Table 4:

[0122] Table 4: HLB values calculated by nuclear magnetic resonance method for samples:

[0123] Sample source HLB Oil sample No. 1 2.03 Oil sample No. 2 2.46 Oil sample No. 3 4.32 Oil sample No. 4 2.24 Oil sample No. 5 1.88 Oil sample No. 6 2.01 Oil sample No. 7 2.47 Oil sample No. 8 2.33 Oil sample No. 9 4.24 Oil sample No. 10 2.58 Oil sample No. 11 3.00 Oil sample No. 12 3.66 Oil sample No. 13 3.88 Oil sample No. 14 4.00 Oil sample No. 15 4.26 Oil sample No. 16 4.57 Oil sample No. 17 4.68 Oil sample No. 18 5.79

[0124] Step 4: Select the structural parameters with a correlation degree with the HLB value for fitting to obtain a single-factor fitting formula:

[0125] The correlation fitting between the HLB value and the aromatic carbon ratio f A is as shown in Figure 2 , and the fitting formula is obtained:

[0126] HLB = 12.101f A -2.5335

[0127] The correlation fitting between the HLB value and the hydrogen substitution rate σ of the aromatic ring system is as shown in Figure 3, the fitting formula is obtained:

[0128] HLB = -3.1114σ + 4.5085

[0129] The correlation fitting between the HLB value and the S element content is as Figure 4 , the fitting formula is obtained:

[0130] HLB = 14.201f S +2.9707

[0131] The correlation fitting between the HLB value and the O element content is as Figure 5 , the fitting formula is obtained:

[0132] HLB = 0.1546f O +2.5976

[0133] Step Five: Multi-factor fitting.

[0134] The aromatic carbon ratio f A , the hydrogen substitution rate σ on the periphery of the aromatic ring system, and the S and O contents are selected for fitting, and the formula is obtained:

[0135] HLB = 5.85f A -2.44σ + 0.08f S +0.03f O +1.04

[0136] Step Six: Compare the results of the NMR method with the fitting formula to determine the final fitting formula:

[0137] HLB = 5.85f A -2.44σ + 0.08f S +0.03f O +1.04

[0138] From Figure 6 it can be seen that there is a high accuracy between the fitting formula obtained by this method and the true value.

[0139] Example 3

[0140] In a specific Example 3 of applying the present invention, 18 groups of oil samples were collected for experiments, and the asphaltenes were distinguished according to the molecular weight of the asphaltenes. Each type of asphaltene was distinguished according to a type of example.

[0141] Example Class One

[0142] The molecular weight of the asphaltenes is between 1000 - 3000 g / mol. It includes oil samples No. 1, 3, 6, 8, and 9.

[0143] Example Class Two

[0144] The molecular weight of asphaltene is between 3000 - 6000 g / mol. It includes oil samples of No. 2, No. 4, No. 5, No. 10, No. 11, No. 12, and No. 13.

[0145] Implementation Category Three

[0146] The molecular weight of asphaltene is between 6000 - 9000 g / mol. It includes oil samples of No. 7, No. 14, No. 15, No. 16, No. 17, and No. 18.

[0147] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

[0148] Except for the technical features described in the specification, the rest are well-known technologies to those skilled in the art.

Claims

1. A method for determining the HLB value of asphaltene based on asphaltene structure, characterized in that: The method for determining the HLB value of asphaltene based on the asphaltene structure includes: Step 1, defining the relative ratio R of the integrated curve area of ​​hydrophilic protons; Step 2, further calculating the HLB value of asphaltene based on the R value; Step 3, using the improved BL method to calculate the average structural parameters of the asphaltene sample; Step 4, performing single factor fitting based on the asphaltene HLB value and the selected related parameters; Step 5, further multi-factor fitting is performed to obtain a linear formula for calculating the HLB value of asphaltene; Step 6, compare the calculation results of the fitting formula with the results of the nuclear magnetic resonance method, and finally determine the calculation formula for the HLB value of asphaltene.

2. The method for determining the HLB value of asphaltene based on asphaltene structure according to claim 1, characterized in that: The method for determining the HLB value of asphaltene based on the asphaltene structure also includes, before step 1, selecting a plurality of experimental samples with different structures to conduct experiments in order to eliminate the randomness of the results.

3. The method for determining the HLB value of asphaltene based on asphaltene structure according to claim 1, characterized in that: In step 1, according to the H NMR spectrum, with 2.5 as the center line, calculate the relative integral curve area ∑H of the hydrophilic protons in the hydrophilic group. (W) The relative integrated curve area of ​​lipophilic protons in the lipophilic group ∑H (O) , and then calculate the relative ratio R of the integrated curve area of ​​hydrophilic protons.

4. The method for determining the HLB value of asphaltene based on asphaltene structure according to claim 3, characterized in that: In step 1, the formula for calculating the relative ratio R of the integrated curve area of ​​hydrophilic protons is: R=∑H (W) / (∑H (W) +∑H (O) )。 5. The method for determining the HLB value of asphaltene based on asphaltene structure according to claim 1, characterized in that: In step 2, the HLB value of asphaltene is further calculated based on the R value calculated by the nuclear magnetic resonance hydrogen spectrum, and the calculation formula is: HLB = 60R / (R+2).

6. The method for determining the HLB value of asphaltene based on asphaltene structure according to claim 1, characterized in that: In step 3, the average structural parameters of the asphaltene samples were calculated using the modified BL method, as shown in Table 1: Table 1 Calculation formulas of parameters of the improved BL method in, C T Indicates the total number of carbons in a molecule; C A Indicates the number of aromatic carbons in the molecule; C N It indicates the number of cycloalkane carbons in the molecule; C p Indicates the number of alkyl carbons in the molecule; C α represents the α-position carbon; C AP Indicates the number of peripheral carbon atoms in the aromatic ring system; H AU / C A Aromatic ring system condensation degree parameter; H T It represents the total number of hydrogen atoms in the average molecule; H A represents a hydrogen atom directly attached to an aromatic carbon; H α represents a hydrogen atom directly attached to the alpha carbon of an aromatic ring; H β It represents the hydrogen on the β-carbon of the aromatic ring and the hydrogen atoms on the CH2 and CH groups beyond β; H γ It represents the hydrogen atoms at the γ position of the aromatic ring and the CH3 group beyond the γ position.

7. The method for determining the HLB value of asphaltene based on asphaltene structure according to claim 1, characterized in that: In step 4, the following average structural parameters that are easy to obtain and have a greater correlation with the hydrophilicity and lipophilicity of asphaltene are used as correlation parameters: aromatic carbon ratio f A That is, it reflects the number of aromatic rings, the hydrogen substitution rate σ around the aromatic ring system, and the heteroatom N and O content, that is, it reflects the content of polar functional groups. It preliminarily explores the quantitative relationship between the hydrophilicity and lipophilicity of asphaltene and its structure, in order to provide a reference for the subsequent exploration of HLB influencing factors and the study of surface activity.

8. The method for determining the HLB value of asphaltene based on asphaltene structure according to claim 7, characterized in that: In step 4, the selected parameters are used as independent variables, and the HLB values ​​measured in the experiment are used as dependent variables for data processing. The scatter plot method is used for plotting. The scatter plot is plotted by adding trend lines to obtain the correlation equation, that is, the single factor analysis result is obtained.

9. The method for determining the HLB value of asphaltene based on asphaltene structure according to claim 1, characterized in that: In step 5, by fitting single factors, it is found that the selected parameters are linearly correlated with the HLB value. Due to the complexity of the asphaltene structure, further multi-factor fitting is selected to obtain the linear formula for calculating the HLB value of asphaltene.

10. The method for determining the HLB value of asphaltene based on asphaltene structure according to claim 9, characterized in that: In step 5, the HLB value measured by NMR is used as the dependent variable, and the four structural parameters, namely, O content, f O 、S content S , aromatic carbon rate f A , the hydrogen substitution rate σ around the aromatic ring system is used as the independent variable for linear fitting. Since most methods for calculating HLB values ​​are linear, the formula type mainly selects linear attempts to finally obtain the fitting formula.

11. The method for determining the HLB value of asphaltene based on asphaltene structure according to claim 10, characterized in that: In step 5, the HLB value of asphaltene is further calculated based on the R value calculated by the nuclear magnetic resonance hydrogen spectrum, and the calculation formula is: HLB=60R / (R+2) The fitting formula for determining the HLB value of asphaltene is: HLB=5.85f A -2.44σ+0.08f S +0.03f O +1.04。

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