阅读说明：本技术 一种木质素基双子表面活性剂及其制备方法 (Lignin-based gemini surfactant and preparation method thereof ) 是由 陈淑艳 李学良 陈本寿 周洵平 蔡国星 于 2021-01-28 设计创作，主要内容包括：本发明属于用作驱油剂的木质素衍生物技术领域,具体涉及一种木质素基双子表面活性剂。所述表面活性剂,具有式(I)所示结构式：式中,R为烷基或苯基。本发明的表面活性剂抗盐性能优异,表面活性和界面活性优异,能够满足含钙镁离子较多的油田环境的应用需求。(The invention belongs to the technical field of lignin derivatives used as oil displacement agents, and particularly relates to a lignin-based gemini surfactant. The surfactant has a structural formula shown in a formula (I): wherein R is alkyl or phenyl. The surfactant disclosed by the invention is excellent in salt resistance, surface activity and interfacial activity, and can meet the application requirements of an oil field environment containing more calcium and magnesium ions.)

1. A lignin-based gemini surfactant having the structural formula shown in formula (I):

wherein R is alkyl or phenyl.

2. The method for preparing the surfactant according to claim 1, wherein the lignin-based tertiary amine and 1, 2-dichloroethane are reacted in a solvent at 40 to 80 ℃ for 8 to 14 hours, followed by distillation under reduced pressure, washing, suction filtration and drying.

3. The method of claim 2, wherein the solvent comprises an isopropyl alcohol-water solvent system.

4. The method of claim 3, wherein the concentration of isopropanol in the solvent system is 40 wt% to 80 wt%.

5. The method according to any one of claims 2 to 4, wherein the molar ratio of the lignin-based tertiary amine to 1, 2-dichloroethane is 2:1 to 3.5: 1.

6. The method for preparing a polymer according to any one of claims 2 to 5, wherein the washing is carried out using anhydrous ethanol.

7. The method for preparing a composite material according to any one of claims 2 to 4, comprising the steps of:

the method comprises the steps of carrying out sulfonation reaction on lignin serving as a raw material to obtain lignosulfonate, carrying out epoxy-amination reaction to obtain lignin-based tertiary amine, reacting the lignin-based tertiary amine and 1, 2-dichloroethane in a solvent system at 40-80 ℃ for 8-14h, and then carrying out reduced pressure distillation, washing, suction filtration and drying.

8. The method according to claim 7, wherein the step of performing sulfonation reaction on lignin as a raw material to obtain lignosulfonate comprises the following steps: dissolving lignin in water, adding alkali to completely dissolve the lignin, adding anhydrous sodium sulfite, heating to 130-200 ℃, stirring for reaction for 0.5-3h, and drying the reaction product to obtain lignosulfonate.

9. The method according to claim 8, wherein the mass ratio of the lignin to the anhydrous sodium sulfite is 3:1 to 10: 1.

10. The process according to any one of claims 7 to 9, wherein the epoxy-amination reaction to obtain the lignin-based tertiary amine comprises in particular the following steps: dissolving lignosulfonate in water, adding epoxy chloropropane, and reacting at 30-90 deg.C for 3-10 hr to obtain epoxy lignin; and then mixing the epoxy lignin with organic amine, and reacting for 4-8 hours at 90-160 ℃ to obtain the lignin-based tertiary amine.

Technical Field

The invention belongs to the technical field of lignin derivatives used as oil displacement agents, and particularly relates to a lignin-based gemini surfactant and a preparation method thereof.

Background

At present, oil fields in China are basically produced by adopting a water injection development mode, most of the oil fields enter the later stage of water injection development, and oil reservoirs after water flooding contain more than 50% of residual oil. The residual oil mainly stays in an oil layer in the form of film, column, cluster and the like, and the capillary force, adhesion force and cohesion force borne by the residual oil cannot be overcome by water drive alone, so that the oil is difficult to drive out. After a proper surfactant (namely tertiary oil recovery) is added into the injected water, the interfacial tension between the injected water and the bottom residual oil can be greatly reduced, the residual oil is displaced, and the recovery ratio is improved (the research progress of the surfactant for oil displacement, heavy oil and the like, fine petrochemical industry, No. 25, No. 4, No. 1-9 of the left column of page 78, No. 7 and month 31 of the public date; the research progress of the temperature-resistant and salt-resistant surfactant for oil displacement, Chen Xirong and the like, petrochemical industry, No. 39, No. 12 of the page 2010, No. 1, No. 12-16 of the left column of page 1307, No. 12 and month 31 of the public date 2010).

The surfactant is an amphiphilic body containing lipophilic groups and hydrophilic groups, is easily distributed on an oil-water interface, reduces the tension of the oil-water interface, reduces the force of oil displacement capillaries, increases the number of the oil displacement capillaries, and thus improves the oil displacement efficiency. Secondly, the surface active agent can change the rock surface from oil-wet to water-wet, reduce the adhesion of oil drops on the rock surface and make the oil drops flow more easily. Moreover, the surfactant has the coalescence effect on the emulsifier of the crude oil, so that oil drops are easier to be taken away by water, and the oil extraction efficiency can be further improved. Along with the deepening of the exploitation degree of the oil field, the oil exploitation bottom layer is deeper and deeper, the requirement of the tertiary oil recovery technology on the surfactant is higher and higher, and the tertiary oil recovery technology also requires good compatibility with the oil reservoir and low cost (research progress of the temperature-resistant and salt-resistant surfactant for oil displacement, Chen Xi Rong and the like, petrochemical industry, No. 39, No. 12, No. 39, No. 1307, right column, No. 2, lines 1-12, and published No. 12 and 31 days 2010).

The hypersalinity oil reservoir provides the performance requirements on salt resistance for the surfactant for oil displacement. However, the existing surfactant has poor salt resistance, is easy to generate precipitate in high-salt mineral reserves, and cannot meet the oil displacement requirements of special application occasions such as the high-salt mineral reserves.

Disclosure of Invention

In view of the above, the present invention aims to provide a surfactant for oil displacement, which has excellent salt tolerance and can meet the oil displacement requirements of special application occasions such as high-salt mineral deposits.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a lignin-based gemini surfactant having the formula of formula (I):

wherein R is alkyl or phenyl.

The invention also aims to protect the preparation method of the surfactant, which comprises the steps of reacting the lignin-based tertiary amine and the 1, 2-dichloroethane in a solvent at 40-80 ℃ for 8-14h, and then carrying out reduced pressure distillation, washing, suction filtration and drying.

Further, the solvent comprises an isopropanol-water solvent system.

Further, the concentration of isopropanol in the solvent system is 40 wt% -80 wt%.

Further, the molar ratio of the lignin-based tertiary amine to the 1, 2-dichloroethane is 2:1 to 3.5: 1.

Further, the washing is specifically performed with absolute ethyl alcohol.

Further, the preparation method of the surfactant comprises the following steps:

the method comprises the steps of carrying out sulfonation reaction on lignin serving as a raw material to obtain lignosulfonate, carrying out epoxy-amination reaction to obtain lignin-based tertiary amine, reacting the lignin-based tertiary amine and 1, 2-dichloroethane in a solvent system at 40-80 ℃ for 8-14h, and then carrying out reduced pressure distillation, washing, suction filtration and drying.

Further, the method for preparing the lignosulfonate by performing sulfonation reaction on lignin serving as a raw material comprises the following steps: dissolving lignin in water, adding alkali to completely dissolve the lignin, adding anhydrous sodium sulfite, heating to 130-200 ℃, stirring for reaction for 0.5-3h, and drying the reaction product to obtain lignosulfonate.

Further, the base includes sodium hydroxide or potassium hydroxide.

Further, the mass ratio of the lignin to the anhydrous sodium sulfite is 3:1-10: 1.

Further, the method for obtaining the lignin-based tertiary amine through the epoxy-amination reaction specifically comprises the following steps: dissolving lignosulfonate in water, adding epoxy chloropropane, and reacting at 30-90 deg.C for 3-10 hr to obtain epoxy lignin; and then mixing the epoxy lignin with organic amine, and reacting for 4-8 hours at 90-160 ℃ to obtain the lignin-based tertiary amine.

Further, the organic amine includes one or more of dimethylamine, diethylamine, diethanolamine, N-methylethylamine, N-ethylpropylamine, N-ethyl-2-propylamine, and N-methyl-2-hydroxyethylamine.

The invention has the beneficial effects that:

the surfactant disclosed by the invention is excellent in salt resistance, and can meet the oil displacement requirements of special application occasions such as high-salt mineral reserves and the like.

The surfactant disclosed by the invention is excellent in surface activity and interfacial activity, and can meet the application requirements of an oil field environment containing more calcium and magnesium ions.

The surfactant obtained by the invention has the characteristics of environmental friendliness, easiness in biodegradation and the like, and is an oil displacement agent with wide application prospect.

The preparation method of the invention has simple process and the product is non-toxic and harmless.

The raw materials adopted by the invention are natural renewable biomass resources, the cost is low, and the production cost can be effectively reduced; and the recycling of resources is realized, and the method is safer and more environment-friendly.

Drawings

FIG. 1 is an infrared spectrum of the raw material lignin and the produced surfactant used in example 1, wherein A is an infrared spectrum of the raw material alkali lignin and B is an infrared spectrum of the surfactant; the abscissa is the wave number and the ordinate is the light transmittance;

FIG. 2 is a gamma-c curve (30 ℃ C.) of the surfactants obtained in example 1 and example 2, wherein the abscissa is the amount concentration of the substance and the ordinate is the surface tension;

FIG. 3 is a salt tolerance curve (30 ℃) of the surfactants obtained in examples 1 and 2, in which the abscissa is the concentration of NaCl solution and the ordinate is interfacial tension;

FIG. 4 is a plot of the calcium resistance of the surfactants prepared in examples 1 and 2 (30 ℃ C.), with CaCl on the abscissa₂The concentration of the solution and the ordinate are interfacial tension;

FIG. 5 is a graph of oil-water interfacial tension between the surfactant formulated displacement fluids from examples 1 and 2 and Beijing-11 crude oil, wherein the abscissa is time and the ordinate is interfacial tension.

Detailed Description

The examples are provided for better illustration of the present invention, but the present invention is not limited to the examples. Therefore, those skilled in the art should make insubstantial modifications and adaptations to the embodiments of the present invention in light of the above teachings and remain within the scope of the invention.

Example 1

The lignin-based gemini surfactant is prepared from the following raw materials in the following steps:

A. weighing 10g of lignin, dissolving the lignin in 100mL of distilled water, adding 40g of 20 wt% sodium hydroxide solution, stirring until the lignin is completely dissolved, adding 2g of anhydrous sodium sulfite, and heating to 180 ℃ for reaction for 0.5 hour; taking out, cooling, adjusting pH to about 2 with dilute sulfuric acid, centrifuging to separate out precipitate, drying, and grinding to obtain brown powder, i.e. lignosulfonate;

B. dissolving 0.10mol of lignosulfonate in 100mL of distilled water, then adding 20g of 20 wt% sodium hydroxide solution, stirring until the lignosulfonate is completely dissolved, heating to 60 ℃, dropwise adding 0.12mol of epoxy chloropropane, and reacting at 70 ℃ for 6 hours to obtain epoxy lignin; then, adding 0.10mol of the obtained epoxy lignin into 100mL of distilled water for full dissolution, dropwise adding 0.12mol of dimethylamine, and reacting for 6 hours at 140 ℃ to obtain lignin-based tertiary amine;

C. weighing 0.22mol of lignin-based tertiary amine, dissolving the lignin-based tertiary amine in 200g of isopropanol-water solvent system with the mass fraction of 50 wt%, adding 0.10mol of 1, 2-dichloroethane, reacting at 60 ℃ for 10 hours, carrying out reduced pressure distillation to remove the solvent, washing the product with 100mL of absolute ethyl alcohol for 3 times, carrying out suction filtration and drying to obtain the lignin-based gemini surfactant.

Example 2

The parameters of this example were set to the same values as in example 1, except that diethanolamine was used as the organic amine.

Infrared spectroscopy detection

Infrared spectrum detection is respectively carried out on the raw material lignin adopted in the embodiment 1 and the prepared surfactant, and the specific parameters are as follows: and performing structural characterization on the synthesized lignin-based gemini surfactant by using a Thermo 6700 Fourier infrared-Raman spectrometer, wherein the wavelength scanning range is selected from 400-4000 cm < -1 >, and the result is shown in figure 1.

As can be seen from FIG. 1, the surfactant prepared in example 1 has strong absorption peaks at 2934cm-1 and 2810cm-1 compared with the raw material lignin, indicating that C-H stretching vibration exists, and the absorption bands of the regions are widened due to the introduction of long alkyl chains; benzene ring skeleton vibration peaks peculiar to lignin appear at 1627cm-1 and 1440 cm-1; a C-N stretching vibration absorption peak appears at 1440cm < -1 >, and the peak of the C-N stretching vibration absorption peak is coincided with the peak of a benzene ring; a C-N bending vibration absorption peak was observed at 631cm-1, and a small C-N absorption peak was observed at 1030cm-1 to 920 cm-1. Compared with the raw material spectrum, the product has characteristic absorption peaks of S ═ O groups at 1300cm-1 and 1120 cm-1.

In conclusion, the target product is successfully synthesized.

Performance detection

The surface tension, salt tolerance, calcium resistance, and oil-water interfacial tension between the crude oil and the displacement fluid of beijing-11 were measured for the surfactants prepared in examples 1 and 2, and the results are shown in fig. 2-5, wherein,

FIG. 2 is a gamma-c curve (30 ℃ C.) of the surfactants obtained in example 1 and example 2;

FIG. 3 is a salt tolerance curve (30 ℃ C.) for the surfactants prepared in examples 1 and 2;

FIG. 4 is a graph showing the calcium resistance property (30 ℃ C.) of the surfactants obtained in example 1 and example 2;

FIG. 5 is a graph of the oil-water interfacial tension between the displacement fluid formulated with the surfactants prepared in examples 1 and 2 and Beijing-11 crude oil;

the detection method of the surface tension comprises the following steps: preparing a series of solutions with different concentrations by taking the prepared surfactant as a solute and distilled water as a solvent, wherein the mass concentration range is 0.001g/L-10.00 g/L; measuring the surface tension of the lignin-based gemini surfactant aqueous solution by adopting a Wilhelmy hanging method; the method specifically comprises the following steps: measuring surface tension by using a QBZY type surface tension meter, loading about 20mL of sample to be measured into a sample pool, then hanging a burned platinum hanging piece on a hook of the surface tension meter, and starting measurement when the hanging piece is static; testing the surface tension value of each concentration of aqueous solution three times, and solving the average value gamma of the aqueous solution; drawing a gamma-C curve of the solution, and calculating the critical micelle concentration cmc of the surfactant according to the inflection point of the curve;

the salt tolerance detection method comprises the following steps: preparing an oil displacement agent monomer with the mass fraction of 0.3 wt% by taking the prepared surfactant as a solute and distilled water as a solvent, wherein the concentration range of NaCl in a solution system is 0.5-5.0 wt%, and measuring the oil-water interfacial tension between the crude oil of Huabeijing-11 and the displacement fluid at 54 ℃; the method specifically comprises the following steps: the interfacial tension is measured by a TX-500 video rotary drop ultra-low interfacial tensiometer, and the measuring rotating speed is 12ms rev^-1(ii) a The measurement temperature is 54 ℃ of the mineral storage temperature of the North China crude oil; reading for 1 time every 10min, and measuring for about 2 hours until the difference between 3 continuous readings is within 0.001cm, namely determining that the system is balanced, and finishing the measurement;

the method for detecting the calcium resistance comprises the following steps: preparing 0.3 wt% oil-displacing agent monomer with CaCl in solution system by using the prepared surfactant as solute and distilled water as solvent₂The concentration range of the displacement fluid is 0.2 to 2.0 weight percent, and the oil-water interfacial tension between the crude oil of Huabeijing-11 and the displacement fluid is measured at 54 ℃; the method specifically comprises the following steps: the interfacial tension is measured by a TX-500 video rotary drop ultra-low interfacial tensiometer, and the measuring rotating speed is 12ms rev^-1(ii) a The measurement temperature is 54 ℃ of the mineral storage temperature of the North China crude oil; reading 1 time every 10min for about 2 hours until 3 consecutive readingsThe difference value of the two-dimensional data is within 0.001cm, the system is determined to be balanced, and the determination is finished;

the method for detecting the oil-water interfacial tension between the Huabeijing-11 crude oil and the displacement fluid comprises the following steps: preparing an oil displacement agent monomer with the mass fraction of 0.3 wt% by taking the prepared surfactant as a solute and formation water (the total salinity is 10789mg/L) in North China as a solvent, and measuring the oil-water interfacial tension between crude oil in Beijing-11 and a displacement fluid at 54 ℃; the method specifically comprises the following steps: the interfacial tension is measured by a TX-500 video rotary drop ultra-low interfacial tensiometer, and the measuring rotating speed is 12ms rev^-1(ii) a The measurement temperature is 54 ℃ of the mineral storage temperature of the North China crude oil; reading for 1 time every 10min, and measuring for about 2 hours until the difference between 3 continuous readings is within 0.001cm, thus determining that the system is balanced and finishing the measurement.

As is clear from FIG. 2, the surfactants obtained in example 1 and example 2 were excellent in surface activity, and had critical micelle concentrations of 0.098mmol/L and 0.094mmol/L, respectively, and surface tensions of 24.54mN/m and 23.87mN/m, respectively, at the critical micelle concentrations.

As can be seen from FIG. 3, when the concentration of the NaCl solution is 3.0 wt%, the interfacial tension of the surfactant in example 1 reaches a minimum of 0.00148mN/m, and when the concentration of the NaCl solution is increased, the interfacial tension of the solution starts to increase until 4.0 wt%, the interfacial tension is 0.00365mN/m, and the oil displacement requirement is still met. When the concentration of the NaCl solution is 3.0 wt%, the interfacial tension of the surfactant in the embodiment 2 reaches the lowest 0.00102mN/m, the concentration of the NaCl solution is continuously improved, the interfacial tension of the solution starts to increase, and the interfacial tension is 0.00876mN/m until 5.0 wt%, so that the oil displacement requirement is still met. Thus, the surfactant of the present invention is excellent in salt resistance.

As can be seen from FIG. 4, when CaCl is added₂When the concentration of the solution is 1.0 wt%, the interfacial tension of the surfactants of the examples 1 and 2 reaches the lowest of 0.00411mN/m and 0.00329mN/m respectively, and CaCl is continuously increased₂The concentration of the solution and the interfacial tension of the solution start to increase until the concentration reaches 1.5 wt%, the interfacial tensions are 0.00746mN/m and 0.00865mN/m respectively, and the oil displacement requirement is still met. Thus, the surfactant of the present invention is excellent in calcium resistance.

As can be seen from FIG. 5, the surfactants of examples 1 and 2 can reduce the oil-water interfacial tension to 0.00137mN/m and 0.00124mN/m, respectively, at higher total salinity concentrations of the formation brine. Therefore, the surfactant disclosed by the invention is higher in surface activity and interfacial activity, and can meet the application requirements of oil field environments containing more calcium and magnesium ions.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.