Special demulsifier for desalting heavy fuel oil for gas turbine and preparation method thereof

Abstract

The invention relates to the technical field of desalting demulsifiers, and discloses a special demulsifier for desalting heavy fuel oil for a gas turbine and a preparation method of the special demulsifier. Polyethylene glycol monomethyl ether and 4-((dimethylamino) methyl) benzoic acid are subjected to an esterification reaction to obtain tertiary amino polyethylene glycol monomethyl ether; and performing quaternization reaction with bromine atoms of the modified phenolic resin to obtain the special demulsifier for desalting the heavy fuel oil for the gas turbine. The demulsifying agent takes phenolic resin as a matrix, cationic groups and polyether chain segments are introduced into side chains of the phenolic resin, the demulsifying agent has very strong surface activity and shows very high desalination and dehydration performance, the dehydration rate reaches 87.2-93.5% in 18 hours, and after testing for 7 days, the salt content of heavy fuel oil after electric desalination is only 3.4-6.6 mg / L.

Description

Technical Field

[0001] The invention relates to the technical field of desalting demulsifiers, in particular to a demulsifier special for desalting heavy fuel oil for gas turbines and a preparation method thereof. Background Art

[0002] Crude oil, heavy fuel oil and other fuels contain a certain amount of water and inorganic salts, which seriously affect the quality and combustion performance of the fuel. Crude oil demulsifier is a functional additive used in oil field exploitation, electric desalting system of oil refining equipment and other fields. Crude oil demulsifier can destroy the emulsified state of oil and water in crude oil, promote oil and water separation, thereby realizing the desalting and dehydration of crude oil and improving the quality of crude oil.

[0003] Common crude oil demulsifiers mainly include non-ionic demulsifiers and ionic demulsifiers. Among them, the non-ionic demulsifier obtained by polymerizing phenolic resin with polyoxyethylene and polyoxypropylene has good demulsification performance and is widely used. Patent CN105885029B discloses a polyether demulsifier based on alcohol amine modified phenolic resin and a synthesis method thereof. The polyether macromolecular demulsifier obtained by using alcohol amine modified phenolic resin as an initiator and block polymerization with propylene oxide and ethylene oxide can effectively reduce the oil-water interface strength and achieve rapid demulsification. It can be used as a demulsifier for dehydration of oil field output liquid and dehydration and desalination of refineries. However, the demulsifier does not show good desalination performance. Cationic demulsifiers have high surface activity, diverse preparation methods, strong demulsification performance, and have broad application prospects in oil field exploitation, demulsifiers, etc. Summary of the invention

[0004] The technical problem solved by the invention is to provide a method for preparing a special demulsifier for desalting heavy fuel oil for gas turbines, thereby solving the problem of poor dehydration and desalting performance of phenolic resin polyether demulsifier.

[0005] The technical solution provided by the present invention is: a method for preparing a demulsifier specially used for desalting heavy fuel oil for gas turbines, comprising the following steps:

[0006] (1) Add phenolic resin to N,N-dimethylformamide, add 4-bromobutyryl chloride and triethylamine after stirring, stir to react, distill the solution under reduced pressure, add water, stand for stratification, remove the water phase, dry, and obtain modified phenolic resin. The reaction formula is as follows:

[0007]

[0008] (2) Add modified phenolic resin and tertiary amino polyethylene glycol monomethyl ether to N,N-dimethylformamide, stir to react, distill the solution under reduced pressure, and dry to obtain a demulsifier for desalting heavy fuel oil for gas turbines. The reaction formula is as follows:

[0009]

[0010] Preferably, in (1), the mass of 4-bromobutyryl chloride and triethylamine are 30-80% and 18-50% of the mass of the phenolic resin, respectively.

[0011] Preferably, the reaction temperature in (1) is 20-30°C and the reaction time is 18-24h.

[0012] Preferably, the mass of the tertiary amino polyethylene glycol monomethyl ether in (2) is 150-800% of the mass of the modified phenolic resin.

[0013] Preferably, the reaction temperature in (2) is 120-140° C., and the reaction time is 48-72 h.

[0014] Preferably, the preparation method of tertiary amino polyethylene glycol monomethyl ether is: add polyethylene glycol monomethyl ether 750-2000, 4-((dimethylamino)methyl)benzoic acid, p-toluenesulfonic acid to toluene, heat to 90-100°C, stir and react for 6-10h, distill under reduced pressure, wash with petroleum ether, and dry to obtain tertiary amino polyethylene glycol monomethyl ether. The reaction formula is as follows:

[0015]

[0016] Preferably, the molar amounts of 4-((dimethylamino)methyl)benzoic acid and p-toluenesulfonic acid are 120-180% and 7-10% of the molar amount of polyethylene glycol monomethyl ether.

[0017] The present invention also provides a demulsifier specially used for desalting heavy fuel oil for gas turbines prepared according to the preparation method.

[0018] The technical effect of the present invention is as follows: tertiary amine polyethylene glycol monomethyl ether is obtained by esterification reaction with 4-((dimethylamino)methyl)benzoic acid, and then quaternization reaction is carried out with bromine atoms of modified phenolic resin to obtain a demulsifier for desalting heavy fuel oil for gas turbine. The demulsifier uses phenolic resin as a matrix, introduces cationic groups and polyether segments into its side chains, has strong surface activity, and exhibits high desalting and dehydration performance. The dehydration rate reaches 87.2-93.5% at 18 hours. After 7 days of testing, the salt content of heavy fuel oil after electrical desalination is only 3.4-6.6 mg / L. DETAILED DESCRIPTION

[0019] The following is a detailed description of the embodiments. However, various modifications can be made to the embodiments, and the scope of the present invention is not limited or defined by the embodiments. All variations, equivalents or substitutes of the embodiments are included in the scope of the rights.

[0020] Example 1

[0021] (1) Add 10 mmol polyethylene glycol monomethyl ether 1500, 12 mmol 4-((dimethylamino)methyl)benzoic acid (CAS No. 18364-71-1), and 0.8 mmol p-toluenesulfonic acid to 30 mL of toluene, heat to 100°C, stir to react for 8 hours, distill under reduced pressure, wash with petroleum ether, and dry to obtain tertiary amino polyethylene glycol monomethyl ether.

[0022] (2) Add 3 g of phenolic resin to 50 mL of N,N-dimethylformamide, stir, then add 1.5 g of 4-bromobutyryl chloride and 0.86 g of triethylamine, stir and react at 20°C for 24 h, distill the solution under reduced pressure, add water, let stand to separate the layers, remove the aqueous phase, and dry to obtain a modified phenolic resin.

[0023] (3) Add 5 g of modified phenolic resin and 7.5 g of tertiary amino polyethylene glycol monomethyl ether to 300 mL of N,N-dimethylformamide, heat to 120° C., stir and react for 60 h, distill the solution under reduced pressure, and dry to obtain a demulsifier specifically for desalting heavy fuel oil for gas turbines.

[0024] Example 2

[0025] (1) Add 10 mmol polyethylene glycol monomethyl ether 1000, 12 mmol 4-((dimethylamino)methyl)benzoic acid, and 0.7 mmol p-toluenesulfonic acid to 40 mL toluene, heat to 90°C, stir and react for 10 hours, evaporate under reduced pressure, wash with petroleum ether, and dry to obtain tertiary amino polyethylene glycol monomethyl ether.

[0026] (2) Add 3 g of phenolic resin to 80 mL of N,N-dimethylformamide, stir, then add 2.4 g of 4-bromobutyryl chloride and 1.5 g of triethylamine, stir and react at 30°C for 18 h, distill the solution under reduced pressure, add water, let stand to separate the layers, remove the aqueous phase, and dry to obtain a modified phenolic resin.

[0027] (3) Add 5 g of modified phenolic resin and 18.2 g of tertiary amino polyethylene glycol monomethyl ether to 400 mL of N,N-dimethylformamide, heat to 140° C., stir and react for 48 hours, distill the solution under reduced pressure, and dry to obtain a demulsifier specifically for desalting heavy fuel oil for gas turbines.

[0028] Example 3

[0029] (1) Add 10 mmol polyethylene glycol monomethyl ether 2000, 18 mmol 4-((dimethylamino)methyl)benzoic acid, and 1 mmol p-toluenesulfonic acid to 40 mL of toluene, heat to 90°C, stir and react for 10 hours, evaporate under reduced pressure, wash with petroleum ether, and dry to obtain tertiary amino polyethylene glycol monomethyl ether.

[0030] (2) Add 3 g of phenolic resin to 50 mL of N,N-dimethylformamide, stir, then add 0.9 g of 4-bromobutyryl chloride and 0.54 g of triethylamine, stir and react at 20°C for 24 h, distill the solution under reduced pressure, add water, let stand to separate the layers, remove the aqueous phase, and dry to obtain a modified phenolic resin.

[0031] (3) Add 5 g of modified phenolic resin and 29.5 g of tertiary amino polyethylene glycol monomethyl ether to 400 mL of N,N-dimethylformamide, heat to 140° C., stir and react for 60 h, distill the solution under reduced pressure, and dry to obtain a demulsifier specifically for desalting heavy fuel oil for gas turbines.

[0032] Example 4

[0033] (1) Add 10 mmol polyethylene glycol monomethyl ether 750, 15 mmol 4-((dimethylamino)methyl)benzoic acid, and 1 mmol p-toluenesulfonic acid to 30 mL toluene, heat to 100°C, stir and react for 6 hours, evaporate under reduced pressure, wash with petroleum ether, and dry to obtain tertiary amino polyethylene glycol monomethyl ether.

[0034] (2) Add 3 g of phenolic resin to 70 mL of N,N-dimethylformamide, stir, then add 1.9 g of 4-bromobutyryl chloride and 1.18 g of triethylamine, stir and react at 25°C for 24 h, distill the solution under reduced pressure, add water, let stand to separate the layers, remove the aqueous phase, and dry to obtain a modified phenolic resin.

[0035] (3) Add 5 g of modified phenolic resin and 40 g of tertiary amino polyethylene glycol monomethyl ether to 400 mL of N,N-dimethylformamide, heat to 130° C., stir and react for 72 h, distill the solution under reduced pressure, and dry to obtain a demulsifier specifically for desalting heavy fuel oil for gas turbines.

[0036] Comparative Example 1

[0037] (1) Add 3 g of phenolic resin to 50 mL of N,N-dimethylformamide, stir, then add 1.5 g of 4-bromobutyryl chloride and 0.86 g of triethylamine, stir and react at 20°C for 24 h, distill the solution under reduced pressure, add water, let stand to separate, remove the aqueous phase, and dry to obtain a modified phenolic resin.

[0038] (2) Add 5 g of modified phenolic resin and 7.5 g of methyl 4-((dimethylamino)methyl)benzoate (CAS No. 18153-53-2) to 300 mL of N,N-dimethylformamide, heat to 120°C, stir and react for 60 hours, distill the solution under reduced pressure, and dry to obtain a demulsifier.

[0039] Comparative Example 2

[0040] (1) Add 15 g of polyethylene glycol monomethyl ether 1500, 1.1 g of succinic anhydride, 0.1 g of 4-dimethylaminopyridine, and 1.2 g of triethylamine to 100 mL of dichloromethane, stir and react at 25° C. for 12 h, evaporate under reduced pressure, wash with petroleum ether, and dry. Add the product to 80 mL of toluene, add 22 g of thionyl chloride, stir and react at 70° C. for 24 h, evaporate under reduced pressure, and dry to obtain acyl chloride polyethylene glycol monomethyl ether.

[0041] (2) Add 3 g of phenolic resin to 80 mL of N,N-dimethylformamide, stir, then add 10.9 g of acyl chloride polyethylene glycol monomethyl ether and 1.5 g of triethylamine, stir and react at 30°C for 18 h, distill the solution under reduced pressure, add water, let stand to separate, remove the aqueous phase, and dry to obtain a demulsifier.

[0042] The demulsifier evaluation method is tested according to the industry standards SY / T5280-2018 and SY T 5281-2000. The sample crude oil is heavy fuel oil. The demulsifier dosage is 18 mg / L.

[0043] Table 1 Demulsifier dehydration rate test

[0044]

[0045] Table 2 Salt content test of electrical desalination heavy fuel oil

[0046]

[0047] After testing, the special demulsifier for desalting heavy fuel oil for gas turbines in Examples 1-4 uses phenolic resin as a matrix, introduces cationic groups and polyether segments into its side chains, has strong surface activity, and exhibits high desalting and dehydration performance. The dehydration rate reaches 87.2-93.5% in 18 hours. After 7 days of testing, the salt content of the heavy fuel oil after electrical desalination is only 3.4-6.6 mg / L.

[0048] In Comparative Example 1, a quaternization reaction was carried out between a modified phenolic resin and the tertiary amine group of methyl 4-((dimethylamino)methyl)benzoate. The side chain of the obtained phenolic resin-based demulsifier did not contain a polyether segment, had poor surface activity, and had poor desalination and dehydration performances. The dehydration rate was only 24.9% at 18 h. After 7 days of testing, the salt content of the heavy fuel oil after electrical desalination reached 63.4 mg / L.

[0049] Comparative Example 2 utilizes the hydroxyl group of phenolic resin to react with the acyl chloride group of acyl chloride polyethylene glycol monomethyl ether. The side chain of the obtained phenolic resin-based demulsifier contains a polyether segment, but does not contain a cationic group. The surface activity is poor, and the desalination and dehydration performances are average. The dehydration rate is only 66.9% at 18 hours. After 7 days of testing, the salt content of the heavy fuel oil after electrical desalination reaches 19.3 mg / L.

[0050] In summary, the embodiments are described through limited embodiments, and a person skilled in the art can make various modifications and variations to the above descriptions. For example, the described techniques are performed in a different order from the described methods, and / or the described constituent elements are combined or combined in a different form from the described methods, or replaced or substituted by other constituent elements or equivalents to obtain the same effect.

Claims

1. A method for preparing a demulsifier for desalting heavy fuel oil for gas turbines, characterized in that: The preparation method comprises the following steps: (1) Add phenolic resin to N,N-dimethylformamide, add 4-bromobutyryl chloride and triethylamine after stirring, stir to react, distill the solution under reduced pressure, add water, stand for stratification, remove the aqueous phase, and dry to obtain a modified phenolic resin; (2) Add modified phenolic resin and tertiary amino polyethylene glycol monomethyl ether to N,N-dimethylformamide, stir to react, distill the solution under reduced pressure, and dry to obtain a demulsifier specifically for desalting heavy fuel oil for gas turbines.

2. The method for preparing a demulsifier for desalting heavy fuel oil for gas turbine according to claim 1, characterized in that: In the above (1), the mass of 4-bromobutyryl chloride and triethylamine are 30-80% and 18-50% of the mass of the phenolic resin respectively.

3. The method for preparing a demulsifier for desalting heavy fuel oil for gas turbine according to claim 1, characterized in that: The stirring reaction temperature in (1) is 20-30°C, and the reaction time is 18-24h.

4. The method for preparing a demulsifier for desalting heavy fuel oil for gas turbine according to claim 1, characterized in that: The mass of the tertiary amino polyethylene glycol monomethyl ether in (2) is 150-800% of the mass of the modified phenolic resin.

5. The method for preparing a demulsifier for desalting heavy fuel oil for gas turbine according to claim 1, characterized in that: The stirring reaction temperature in (2) is 120-140°C, and the reaction time is 48-72h.

6. The method for preparing a demulsifier for desalting heavy fuel oil for gas turbine according to claim 1, characterized in that: The preparation method of the tertiary amino polyethylene glycol monomethyl ether comprises: adding polyethylene glycol monomethyl ether, 4-((dimethylamino)methyl)benzoic acid and p-toluenesulfonic acid into toluene, stirring for reaction, performing reduced pressure distillation, washing and drying to obtain the tertiary amino polyethylene glycol monomethyl ether.

7. The method for preparing a demulsifier for desalting heavy fuel oil for gas turbine according to claim 6, characterized in that: The molar amounts of the 4-((dimethylamino)methyl)benzoic acid and p-toluenesulfonic acid are 120-180% and 7-10% of the molar amount of the polyethylene glycol monomethyl ether respectively.

8. The method for preparing a demulsifier for desalting heavy fuel oil for gas turbine according to claim 6, characterized in that: The molecular weight of the polyethylene glycol monomethyl ether is 750-2000.

9. The method for preparing a demulsifier for desalting heavy fuel oil for gas turbine according to claim 6, characterized in that: The reaction is carried out at 90-100°C for 6-10 h.

10. A demulsifier specially used for desalting heavy fuel oil for gas turbines prepared according to the preparation method according to any one of claims 1 to 9.

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