CN114958416B

CN114958416B - Application of bio-based wetting agent, composition for treating iron-containing sulfide, treatment method and application

Info

Publication number: CN114958416B
Application number: CN202110199863.6A
Authority: CN
Inventors: 王振宇; 于丽; 陆语; 张峰; 沈明欢; 苗杰
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2021-02-22
Filing date: 2021-02-22
Publication date: 2023-07-14
Anticipated expiration: 2041-02-22
Also published as: CN114958416A

Abstract

The invention relates to the field of petrochemical industry, and discloses application of a bio-based wetting agent, a composition for treating iron-containing sulfide, a treatment method and application. The composition for treating the iron-containing sulfide contains the following components which are stored independently or stored in a mixed way: a bio-based wetting agent, a water-soluble demulsifier; the bio-based wetting agent is sophorolipid ether. When the bio-based wetting agent disclosed by the invention is used for treating emulsified crude oil with higher iron-containing sulfide, the iron-containing sulfide in the emulsified crude oil can be effectively removed.

Description

Application of bio-based wetting agent, composition for treating iron-containing sulfide, treatment method and application

Technical Field

The invention relates to the field of petrochemical industry, in particular to application of a bio-based wetting agent, a composition for treating iron-containing sulfide, a treatment method and application.

Background

Crude oil contains impurities such as salt, sediment, water (Bs & W), solids, metals and the like, and the presence of the impurities can lead to corrosion, heat exchanger scaling, furnace coking, catalyst deactivation and product quality degradation.

Solids in crude oil include silt, clay, volcanic ash, drilling mud, ferrous sulfide, scale and the like, wherein crude oil containing iron sulfide solid particles can cause serious emulsification problems, particularly thick oil containing iron sulfide solid particles, the very fine iron sulfide solid particles form a crude oil emulsion layer at an oil-water interface, the phenomenon of current rise or tripping can be caused, in addition, thickening of the emulsion layer can cause the increase of drainage oil content, dirty oil recovered from oily wastewater is difficult to treat, impact is caused to electric desalting if the oil is recycled, and the deterioration of electric desalting operation is aggravated. Therefore, how to solve the problem of emulsification caused by solid particles of iron sulfide becomes a hot spot of researchers at home and abroad.

CN108264926a discloses a method for treating emulsified crude oil containing iron sulfide solid particles, which uses an oil-soluble demulsifier to treat the emulsified crude oil first and then uses a water-soluble demulsifier to treat the emulsified crude oil to obtain an oil phase.

Disclosure of Invention

The invention aims to solve the problems that the emulsified crude oil containing iron sulfide solid particles cannot be effectively treated by singly adopting a demulsifier and the process for treating the emulsified crude oil is relatively complex in the prior art.

To achieve the above object, the present invention provides in a first aspect the use of a bio-based wetting agent, which is a sophorolipid ether, for treating emulsified crude oil.

In a second aspect, the present invention provides a composition for treating iron-containing sulphides, the composition comprising the following components, each independently or in combination: a bio-based wetting agent, a water-soluble demulsifier;

the bio-based wetting agent is sophorolipid ether;

the water-soluble demulsifier contains glycerol polyoxyethylene polyoxypropylene ether and/or cationic hydroxyl silicone oil;

in the composition, the content mass ratio of the bio-based wetting agent to the water-soluble demulsifier is 1:0.3-30.

In a third aspect the invention provides the use of a composition according to the second aspect for treating emulsified crude oil containing iron sulphide solid particles.

In a fourth aspect the invention provides a method of treating emulsified crude oil containing iron sulphide solid particles, the method comprising:

(1) Mixing emulsified crude oil with each component in the composition in the second aspect in the presence of a solvent, and then performing electric desalting treatment to obtain mixed oil;

(2) And (3) carrying out oil-water separation on the mixed oil to obtain an aqueous phase and an oil phase respectively.

The inventor finds that when the bio-based wetting agent disclosed by the invention is used for treating emulsified crude oil containing iron sulfide, the bio-degradation can be easier than that of the wetting agent in the prior art, and the problem of environmental pollution is avoided.

In particular, the inventor also finds that the bio-based wetting agent disclosed by the invention is used for treating emulsified crude oil with higher iron sulfide content in cooperation with a water-soluble demulsifier with a specific proportion and a specific type, and can be used for removing the iron sulfide in the emulsified crude oil more effectively.

Detailed Description

The endpoints and any values of the ranges disclosed herein are not limited to the precise range or value, and are understood to encompass values approaching those ranges or values. For numerical ranges, one or more new numerical ranges may be found between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point value, in combination with each other, and are to be considered as specifically disclosed herein.

In the present invention, unless otherwise indicated, the pressures are gauge pressures.

In the present invention, unless otherwise specified, the iron element refers to an iron element in a molecular form existing in a solid particle or a complex state. The iron content of the drain water, the iron content of the upper oil and the iron content of the lower oil refer to the content of iron elements in molecular forms existing in a solid particle or a complex state in the corresponding content.

In the present invention, the basic catalyst II and the basic catalyst III are each independently selected from sodium hydroxide and/or potassium hydroxide, unless otherwise stated.

As previously mentioned, a first aspect of the present invention provides the use of a bio-based wetting agent which is a sophorolipid ether in the treatment of emulsified crude oil.

Preferably, the content of iron element in the emulsified crude oil is 100-200ppm.

As previously described, the second aspect of the present invention provides a composition for treating iron-containing sulfides, the composition comprising the following components, each independently or in admixture: a bio-based wetting agent, a water-soluble demulsifier;

the bio-based wetting agent is sophorolipid ether;

Preferably, in the composition, the content mass ratio of the bio-based wetting agent to the water-soluble demulsifier is 1:0.3-20. In this preferred case, significantly more of the iron-containing sulfide solid particles in the emulsified crude oil can be washed into the aqueous phase, significantly increasing the iron content of the drainage.

Preferably, the sophorolipid ether is prepared by a process comprising the steps of:

(a) In the presence of an acid catalyst I, performing a contact reaction I on sophorolipid and methanol to obtain sophorolipid methyl ester;

(b) In the presence of a basic catalyst I, contacting the sophorolipid methyl ester with propylene oxide for reaction II, and contacting the obtained reaction product with ethylene oxide for reaction III.

Preferably, in step (a), the acidic catalyst I is selected from sulfuric acid having a concentration of 70wt% or more. Illustratively, in step (a), the acidic catalyst I is selected from sulfuric acid having a concentration of 70 wt%.

Preferably, in the step (a), the amount of the acidic catalyst I, the sophorolipid and the methanol is 1 by mass: 10-30:30-80.

Preferably, in step (a), the conditions of the contact reaction I comprise: the temperature is 30-50deg.C, and the time is 0.5-5h.

Preferably, in step (b), the basic catalyst I is KOH.

Preferably, in the step (b), the amount of the basic catalyst I, the sophorolipid methyl ester, the propylene oxide and the ethylene oxide is 1 by mass: 300-500:100-200:500-600.

Preferably, in step (b), the conditions of contact reaction II comprise: the temperature is 100-150 ℃, the time is 0.5-5h, and the pressure is 0.1-0.5MPa.

Preferably, in step (b), the conditions of the contact reaction III include: the temperature is 100-150 ℃, the time is 0.5-5h, and the pressure is 0.1-0.5MPa.

Preferably, the water-soluble demulsifier is prepared from the following components in percentage by mass of 2-10:1 and cationic hydroxy silicone oil.

Preferably, the content mass ratio of the glycerol polyoxyethylene polyoxypropylene ether to the cationic hydroxyl silicone oil is 3-7:1. the inventors have found that in this preferred case the process of the present invention is able to wash significantly more of the iron-containing sulphide solid particles in the emulsified crude oil into the aqueous phase, thereby significantly increasing the iron content of the drainage.

In the method of the invention, the glycerol polyoxyethylene polyoxypropylene ether can be obtained commercially or prepared by itself. According to a particularly preferred embodiment, the glycerol polyoxyethylene polyoxypropylene ether is prepared by a process comprising the steps of: in the presence of a basic catalyst II, glycerol and propylene oxide are subjected to a contact reaction IV, and then the obtained intermediate product is subjected to a contact reaction V with ethylene oxide.

Preferably, propylene oxide is used in an amount of 20 to 90mol and ethylene oxide is used in an amount of 10 to 70mol relative to 1mol of glycerol. More preferably, propylene oxide is used in an amount of 50 to 70mol and ethylene oxide is used in an amount of 20 to 50mol with respect to 1mol of glycerol.

Preferably, the basic catalyst II is used in an amount of 0.3 to 2% by weight, based on the total weight of glycerol and propylene oxide.

Preferably, the conditions of the contact reaction IV include: the temperature is 135+ -5deg.C, the pressure is 0.1-0.5MPa, and the time is 15min-120min.

Preferably, the conditions of the contact reaction V include: the temperature is 125+/-5 ℃, the pressure is 0.1-0.5MPa, and the time is 15-120 min.

In the process of the present invention, the cationic hydroxy silicone oils may be obtained commercially or may be prepared by themselves. According to another particularly preferred embodiment, the cationic hydroxy silicone oil is prepared by a process comprising the steps of: adding a cationic emulsifier and an alkaline catalyst III into a reaction container to dissolve the cationic emulsifier and the alkaline catalyst III in water; dropwise adding small molecular siloxane with the weight average molecular weight not higher than 500 into a reaction container under the stirring condition, heating to 50-100 ℃, and reacting at the temperature of 50-100 ℃ for 2-12h; and cooling the reactant, adding glacial acetic acid, and neutralizing to neutrality to obtain the micro blue light semitransparent cationic hydroxyl silicone oil emulsion.

Preferably, the cationic emulsifier is a cationic biquaternary surfactant, further preferably at least one of N, N-di (tetradecyldimethyl) -3-oxa-1, 5-pentanediammonium dibromide, N-di (hexadecyldimethyl) -3-oxa-1, 5-pentanediammonium dibromide, N-di (decayldimethyl) -3-oxa-1, 5-pentanediammonium dibromide.

Preferably, the cationic emulsifier is used in an amount of 1 to 10wt% based on the total weight of the cationic hydroxy silicone oil emulsion.

Preferably, the amount of the alkaline catalyst III is 0.08-0.8wt% of the total weight of the cationic hydroxyl silicone oil emulsion.

Preferably, the small molecule siloxane is octamethyl cyclotetrasiloxane.

Preferably, the octamethyl cyclotetrasiloxane is used in an amount of 20 to 40wt% based on the total weight of the cationic hydroxyl silicone oil emulsion.

As previously mentioned, a third aspect of the invention provides the use of a composition according to the second aspect for treating emulsified crude oil containing solid particles of iron sulphide.

As previously described, a fourth aspect of the present invention provides a method of treating emulsified crude oil containing iron sulphide solid particles, the method comprising:

Preferably, in step (1), the bio-based wetting agent is used in an amount of 50 to 1000. Mu.g and the water-soluble demulsifier is used in an amount of 50 to 150. Mu.g relative to 1g of emulsified crude oil.

Preferably, in step (1), the bio-based wetting agent is used in an amount of 100 to 500. Mu.g and the water-soluble demulsifier is used in an amount of 70 to 120. Mu.g relative to 1g of emulsified crude oil. The inventors have found that with this preferred embodiment, more of the iron-containing sulfide solid particles in the emulsified crude oil can be washed into the aqueous phase, thereby increasing the iron content of the drainage.

Preferably, in step (1), the solvent is water.

Preferably, in the step (1), the ratio of the amount of the emulsified crude oil to the solvent is 3 to 20 by mass: 1, preferably 6-15:1.

preferably, in step (1), the conditions of the electro-desalting treatment include: the temperature is 50-120 ℃, the electric field intensity is 100-300V/cm, and the time is 0.5-3h. More preferably, in step (1), the conditions of the electric desalting treatment include: the temperature is 90-120 ℃, the electric field strength is 150-250V/cm, and the time is 1-2h.

Preferably, the emulsified crude oil has a density of not more than 960g/cm at 20 DEG C ³ At 80 DEG CViscosity of not more than 150mm ² /s。

It should be noted that "I", "II", "III", "IV", "V" in the contact reaction I, the contact reaction II, the contact reaction III, the contact reaction IV, the contact reaction V, and the like in the present invention are only used to indicate that six contact reactions are involved, not the same contact reaction, but this does not represent a sequence unless otherwise specified.

Other metallic elements, such as, for example, calcium or sodium, in emulsified crude oil can also be removed using the method of the present invention, and as the primary concern in the art is the iron content in emulsified crude oil, the primary concern in this context is the treatment of iron in emulsified crude oil.

The invention will be described in detail below by way of examples. In the following examples, all of the raw materials used were commercial products unless otherwise specified.

Sophorolipids: lactone, available from Shandong Qilu Biotechnology group Co., ltd;

methanol: purchased from enokava reagent company;

propylene oxide: purchased from enokava reagent company;

ethylene oxide: purchased from enokava reagent company;

70wt% sulfuric acid: purchased from enokava reagent company;

a water-soluble demulsifier: SP169, purchased from Jihua Liaoyuan chemical industry Co., ltd;

cationic emulsifier: n, N-di (tetradecyldimethyl) -3-oxa-1, 5-pentanediammonium dibromide, available from enokava reagent company;

cationic emulsifier: n, N-di (hexadecyldimethyl) -3-oxa-1, 5-pentanediammonium dibromide, available from enokava reagent company;

cationic emulsifier: n, N-di (deca-dimethyl) -3-oxa-1, 5-pentanediammonium dibromide, available from enokava reagent company;

sophorolipid methyl ester: 50g of sophorolipid is added into 190ml of methanol, stirred into a homogeneous solution, the temperature is controlled to be 40+/-2 ℃, 1.5ml of 70wt% sulfuric acid is added dropwise, and the mixture is reacted for 1.5 hours at 40 ℃ after the dropwise addition is finished;

nonylphenol polyoxyethylene ether: the brand NP7 is purchased from Jiangsu sea Ann petrochemical plant company;

SEM-EDS analysis: and adopting a scanning electron microscope thermogravimetric instrument to carry out analysis and test.

In the following examples, without the contrary:

the properties of the oil blend composed of crude oil and iron-containing sulfide clean tank oil are shown in Table 1.

TABLE 1

Project
		Density (20 ℃), g/cm ³	960.0
Viscosity (80 ℃ C.) mm ² .s ^-1	136.7
		w(Fe)，μg/g	150.8

The emulsified crude oil was washed with xylene, and mechanical impurities were filtered out and analyzed by SEM-EDS, the relative content of each element in the mechanical impurities being shown in table 2. As can be seen from table 2, the mechanical impurities are mainly solid particles of iron sulphide.

TABLE 2

Mechanical impurity element species	Impurity content/wt%
		w(Na)	0.20
w(Mg)	0.43
		w(S)	1.49
w(Ca)	0.78
		w(Fe)	4.19

In each of the examples and comparative examples, the iron content of the wastewater, the iron content of the upper layer oil, and the iron content of the lower layer oil were measured by plasma inductively coupled emission spectrometry (ICP).

Preparation example 1

This preparation example is for explaining the preparation method of glycerol polyoxyethylene polyoxypropylene ether.

Adding 3.7g of glycerol and 1.74g of potassium hydroxide into an autoclave, purging with nitrogen, removing air, vacuumizing, starting stirring, heating to 130 ℃, dropwise adding 170.5g of propylene oxide at the temperature of 135 ℃ under the pressure of 0.3MPa, continuing to react for 0.5h after the dropwise adding is finished, cooling, and discharging to obtain an intermediate product;

100g of intermediate product and 1.86g of potassium hydroxide are added into a high-pressure reaction kettle, nitrogen is used for purging and vacuumizing, stirring is started and the temperature is raised to 120 ℃, 49.6g of ethylene oxide is dropwise added under the conditions of the pressure of 0.3MPa and the reaction temperature of 125 ℃, after the dropwise addition is finished, the reaction is continued for 0.5h, and the glycerol polyoxyethylene polyoxypropylene ether A1 is obtained after cooling and discharging.

Preparation example 2

Adding 3.7g of glycerol and 2g of potassium hydroxide into an autoclave, purging with nitrogen, removing air, vacuumizing, starting stirring, heating to 130 ℃, dropwise adding 197.6g of propylene oxide at the temperature of 135 ℃ under the pressure of 0.3MPa, continuing to react for 0.5h after the dropwise adding is finished, cooling, and discharging to obtain an intermediate product;

100g of intermediate product and 1.32g of potassium hydroxide are added into a high-pressure reaction kettle, nitrogen is used for purging and vacuumizing, stirring is started and the temperature is raised to 120 ℃, 31.6g of ethylene oxide is dropwise added under the conditions of the pressure of 0.3MPa and the reaction temperature of 125 ℃, after the dropwise addition is finished, the reaction is continued for 0.5h, and the glycerol polyoxyethylene polyoxypropylene ether A2 is obtained after cooling and discharging.

Preparation example 3

Adding 3.7g of glycerol and 1.4g of potassium hydroxide into an autoclave, purging with nitrogen, removing air, vacuumizing, starting stirring, heating to 130 ℃, dropwise adding 141.2g of propylene oxide at the temperature of 135 ℃ under the pressure of 0.3MPa, continuing to react for 0.5h after the dropwise adding is finished, cooling, and discharging to obtain an intermediate product;

adding 100g of intermediate product and 1.7g of potassium hydroxide into a high-pressure reaction kettle, purging with nitrogen, vacuumizing, starting stirring, heating to 120 ℃, dropwise adding 73.2g of ethylene oxide under the pressure of 0.3MPa and the temperature of 125 ℃, continuing to react for 0.5h after the dropwise adding is finished, cooling and discharging to obtain the glycerol polyoxyethylene polyoxypropylene ether A3.

Preparation example 4

The preparation example is used for explaining the preparation method of the cationic hydroxyl silicone oil.

Into a four-neck flask equipped with a reflux condenser, a dropping funnel, a stirrer and a thermometer, 0.5g of cationic emulsifier N, N-di (tetradecyldimethyl) -3-oxa-1, 5-glutarimide, 0.04g of catalyst potassium hydroxide and 34.46g of distilled water are added and stirred until the cationic emulsifier and the catalyst are completely dissolved in the water;

then under the condition of stirring, dropwise adding 15g of octamethyl cyclotetrasiloxane into a four-neck flask, gradually heating to 50 ℃, preserving heat and reacting for 2 hours, cooling the reactant after the reaction is stopped, adding glacial acetic acid and neutralizing to be neutral, thus obtaining the semitransparent cation hydroxyl silicone oil emulsion B1 with slight blue light.

Preparation example 5

2g of cationic emulsifier N, N-di (hexadecyldimethyl) -3-oxa-1, 5-glutarimide, 0.16g of catalyst potassium hydroxide and 37.84g of distilled water are added into a four-neck flask provided with a reflux condenser, a dropping funnel, a stirrer and a thermometer, and stirred until the cationic emulsifier and the catalyst are completely dissolved in the water;

then under the condition of stirring, dropwise adding 10g of octamethyl cyclotetrasiloxane into a four-neck flask, gradually heating to 75 ℃, preserving heat and reacting for 6 hours, cooling the reactant after the reaction is stopped, adding glacial acetic acid and neutralizing to be neutral, thus obtaining the semitransparent cation hydroxyl silicone oil emulsion B2 with slight blue light.

Preparation example 6

3.5g of cationic emulsifier N, N-di (deca-dimethyl) -3-oxa-1, 5-glutarimide, 0.28g of catalyst potassium hydroxide and 31.22g of distilled water are added into a four-neck flask with a reflux condenser, a dropping funnel, a stirrer and a thermometer, and stirred until the cationic emulsifier and the catalyst are completely dissolved in the water;

then under the condition of stirring, dropwise adding 15g of octamethyl cyclotetrasiloxane into a four-neck flask, gradually heating to 85 ℃, preserving heat and reacting for 10 hours, cooling the reactant after the reaction is stopped, adding glacial acetic acid and neutralizing to be neutral, thus obtaining the semitransparent cation hydroxyl silicone oil emulsion B3 with slight blue light.

Preparation example 7

This preparation example is used to illustrate the preparation of sophorolipid ether.

50g of sophorolipid is added into 190ml of methanol, stirred into a homogeneous solution, the temperature is controlled to be 40+/-2 ℃, 1.5ml of 70wt% sulfuric acid is added dropwise, and the mixture reacts for 1.5 hours at the temperature of 40 ℃ after the dropwise addition is finished, so that sophorolipid methyl ester is obtained;

adding 100g of sophorolipid methyl ester and 0.25g of KOH into a stainless steel autoclave, replacing air with nitrogen, heating to 130 ℃, dropwise adding 42g of propylene oxide, reacting for 1h under the pressure of 0.3MPa after the dropwise adding is finished, cooling to 120 ℃ after the reaction is finished, dropwise adding 128g of ethylene oxide, and reacting for 1h under the pressure of 0.3MPa after the dropwise adding is finished to obtain sophorolipid ether C1.

Preparation example 8

The procedure of preparation 7 was followed except that 50g of sophorolipid in preparation 7 was replaced with 40g of sophorolipid to obtain sophorolipid ether C2.

Preparation example 9

The procedure of preparation 7 was followed, except that 50g of sophorolipid in preparation 7 was replaced with 60g of sophorolipid, to obtain sophorolipid ether C3.

Example 1

60g of emulsified crude oil is taken, 6000 mug of biological-based wetting agent, 10g of deionized water and 7200 mug of water-soluble demulsifier are added into the emulsified crude oil after the emulsified crude oil is preheated at 85 ℃, the emulsified crude oil is mixed by a mixer, and demulsified and water-separated for 1h under the condition of adding 180V/cm of electric field at 90 ℃. Wherein the bio-based wetting agent is C3, the water-soluble demulsifier is A3+B3, and the content mass ratio of A3 to B3 is 7:1.

and (3) extracting the water phase, adding enough acid to dissolve metal in the water phase, filtering, and measuring the iron content in the filtrate, namely the iron content in the drainage.

Taking 45g of upper layer oil as upper layer oil and 15g of lower layer oil as lower layer oil, and measuring the iron content in the upper layer oil and the lower layer oil respectively.

The test results for each parameter are shown in Table 3.

Example 2

The procedure of example 1 was followed except that 60g of emulsified crude oil was taken, 18000. Mu.g of bio-based wetting agent, 4g of deionized water and 4500. Mu.g of water-soluble demulsifier were added thereto after preheating at 85℃and mixed by a mixer, and demulsified and water-separated for 1.5 hours at 120℃with the application of an electric field of 250V/cm. Wherein the bio-based wetting agent is C2, the water-soluble demulsifier is A2+B2, and the content mass ratio of A2 to B2 is 3:1.

the test results for each parameter are shown in Table 3.

Example 3

The procedure of example 1 was followed except that 60g of emulsified crude oil was taken, and after preheating at 85℃12000. Mu.g of bio-based wetting agent, 6g of deionized water and 6000. Mu.g of water-soluble demulsifier were added thereto, and mixed by a mixer, and demulsified and water-separated for 2 hours at 100℃with an electric field of 200V/cm. Wherein the bio-based wetting agent is C1, the water-soluble demulsifier is A1+B1, and the content mass ratio of A1 to B1 is 5:1.

the test results for each parameter are shown in Table 3.

Example 4

The procedure of example 3 was followed except that the type of bio-based wetting agent was sophorolipid methyl ester.

The test results for each parameter are shown in Table 3.

Example 5

The procedure of example 3 was followed, except that the amount of biobased wetting agent used was 3000. Mu.g.

The test results for each parameter are shown in Table 3.

Example 6

The procedure of example 3 was followed except that the amount of bio-based wetting agent used was 48000. Mu.g.

The test results for each parameter are shown in Table 3.

Example 7

The procedure of example 3 was followed except that the water-soluble demulsifier was all A1.

The test results for each parameter are shown in Table 3.

Example 8

The procedure of example 3 was followed, except that the water-soluble demulsifier (A1+B1) was replaced with an equal mass of water-soluble demulsifier SP 169.

The test results for each parameter are shown in Table 3.

Example 9

The procedure of example 3 was followed except that the amount of the water-soluble demulsifier used was 9000. Mu.g.

The test results for each parameter are shown in Table 3.

Comparative example 1

According to the method of example 3, except that 60g of emulsified crude oil was taken without adding a bio-based wetting agent, 6g of deionized water and 6000. Mu.g of a water-soluble demulsifier (A1+B1, content mass ratio of A1 to B1: 5:1) were added thereto after preheating at 85℃and mixed by a mixer, demulsified and water-separated for 2 hours under the condition of applying an electric field of 200V/cm at 100℃and then measurement of each parameter was carried out.

The test results for each parameter are shown in Table 3.

Comparative example 2

The procedure of example 3 was followed except that the bio-based wetting agent was replaced with equal mass of nonylphenol polyoxyethylene ether.

The test results for each parameter are shown in Table 3.

TABLE 3 Table 3

	Iron content of top oil/(μg/g)	Lower oil iron content/(μg/g)	Iron content/(μg/g) in drainage
				Example 1	60	215.2	520
Example 2	63	218.2	490
				Example 3	55	207.0	570
Example 4	76	231.2	360
				Example 5	68	223.2	440
Example 6	49	204.2	630
				Example 7	61	216.2	510
Example 8	96	270.0	105
				Example 9	52	231.2	540
Comparative example 1	80	274.4	214
				Comparative example 2	75	195.0	450

As can be seen from Table 3, the bio-based wetting agent disclosed by the invention is used for cooperatively matching with a specific content and a specific kind of water-soluble demulsifier to form a composition for treating iron-containing sulfides, and the iron content in drainage can be obviously improved by treating emulsified crude oil with higher iron-containing sulfides by adopting each component in the composition.

Test case

The biodegradability test was carried out on the bio-based wetting agent prepared by the present invention and the nonylphenol polyoxyethylene ether prepared by the comparative example, respectively, and the biodegradability was represented by the ratio (B/C) of biological oxygen consumption (BOD) to chemical oxygen consumption (CODcr), and the specific test results are shown in Table 4.

Wherein BOD is detected by adopting a measuring method of a standard HJ505-2009 'five-day Biochemical oxygen demand of water quality';

CODcr was detected using the standard HJ828-2017 bichromate method for determination of chemical oxygen demand of Water quality.

TABLE 4 Table 4

	B/C
		C1	0.31
C2	0.30
		C3	0.31
Polyoxyethylene nonylphenol ether	0

As can be seen from Table 4, the bio-based wetting agent used in the present invention has better biodegradability than the conventional wetting agent, and does not cause environmental pollution.

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, a number of simple variants of the technical solution of the invention are possible, including combinations of the individual technical features in any other suitable way, which simple variants and combinations should likewise be regarded as being disclosed by the invention, all falling within the scope of protection of the invention.

Claims

1. The use of a bio-based wetting agent for treating emulsified crude oil, characterized in that the bio-based wetting agent is a sophorolipid ether;

wherein the sophorolipid ether is prepared by a method comprising the following steps:

2. Use according to claim 1, wherein the content of elemental iron in the emulsified crude oil is 100-200ppm.

3. A composition for treating iron-containing sulfides, comprising the following components, each independently or in combination: a bio-based wetting agent, a water-soluble demulsifier;

the bio-based wetting agent is sophorolipid ether;

in the composition, the content mass ratio of the bio-based wetting agent to the water-soluble demulsifier is 1:0.3-30;

4. The composition of claim 3, wherein the content mass ratio of the bio-based wetting agent to the water-soluble demulsifier in the composition is 1:0.3-20.

5. The composition according to claim 3 or 4, wherein in step (a), the acidic catalyst I is selected from sulfuric acid having a concentration of 70wt% or more.

6. The composition according to claim 3 or 4, wherein in step (a), the acidic catalyst I, the sophorolipid and the methanol are used in a mass ratio of 1:10-30:30-80.

7. The composition of claim 3 or 4, wherein in step (a), the conditions of contact reaction I comprise: the temperature is 30-50deg.C, and the time is 0.5-5h.

8. The composition according to claim 3 or 4, wherein in step (b), the basic catalyst I is KOH.

9. The composition according to claim 3 or 4, wherein in step (b), the basic catalyst I, the sophorolipid methyl ester, the propylene oxide and the ethylene oxide are used in a mass ratio of 1:300-500:100-200:500-600.

10. The composition of claim 3 or 4, wherein in step (b), the conditions of contact reaction II comprise: the temperature is 100-150deg.C, the time is 0.5-5h, and the pressure is 0.1-0.5Mpa.

11. The composition of claim 3 or 4, wherein in step (b), the conditions of contact reaction III comprise: the temperature is 100-150 ℃, the time is 0.5-5h, and the pressure is 0.1-0.5MPa.

12. The composition according to claim 3 or 4, wherein the water-soluble demulsifier is present in an amount of from 2 to 10 by mass: 1 and cationic hydroxy silicone oil.

13. The composition according to claim 12, wherein the content mass ratio of the glycerol polyoxyethylene polyoxypropylene ether to the cationic hydroxyl silicone oil is 3-7:1.

14. use of a composition according to any one of claims 3-13 for treating emulsified crude oil containing iron sulphide solid particles.

15. A method of treating emulsified crude oil containing iron sulfide solid particles, the method comprising:

(1) Mixing emulsified crude oil with each component in the composition according to any one of claims 3-13 in the presence of a solvent, and then performing electric desalting treatment to obtain mixed oil;

16. The method of claim 15, wherein in step (1), the bio-based wetting agent is used in an amount of 50-1000 μg and the water-soluble demulsifier is used in an amount of 50-150 μg relative to 1g of emulsified crude oil.

17. The method according to claim 15 or 16, wherein in step (1), the bio-based wetting agent is used in an amount of 100 to 500 μg and the water-soluble demulsifier is used in an amount of 70 to 120 μg relative to 1g of emulsified crude oil.

18. A method according to claim 15 or 16, wherein in step (1) the solvent is water.

19. The method according to claim 15 or 16, wherein in step (1), the ratio of the amount of the emulsified crude oil to the solvent is 3 to 20 by mass: 1.

20. the method according to claim 15 or 16, wherein in step (1), the ratio of the amount of the emulsified crude oil to the solvent is 6 to 15 by mass: 1.

21. the method according to claim 15 or 16, wherein in step (1), the conditions of the electric desalting treatment include: the temperature is 60-140 ℃, the electric field intensity is 100-300V/cm, and the time is 0.5-3h.

22. The method according to claim 15 or 16, wherein in step (1), the conditions of the electric desalting treatment include: the temperature is 90-120 ℃, the electric field strength is 150-250V/cm, and the time is 1-2h.

23. The method according to claim 15 or 16, wherein the content of iron element in the emulsified crude oil is 100-200ppm.

24. The method of claim 15 or 16, wherein the emulsified crude oil has a density of not more than 960g/cm at 20 °c ³ Viscosity at 80deg.C is not higher than 150mm ² /s。