Marine fuel oil detergents and methods for their preparation

Abstract

The application relates to the technical field of marine fuel oil additives, and particularly provides a marine fuel oil cleaning synergist and a preparation method thereof. According to mass percentage, the marine fuel oil cleaning synergist comprises the following components: 8-12% of a sulfur capturing agent, 15-20% of a core-shell dispersant, 5-8% of a lubricant, 0.5-1% of an antioxidant and 1-2% of a pour point depressant, and the rest is a solvent. The marine fuel oil cleaning synergist has the advantages of high flash point, sulfur inhibition, combustion strengthening and dispersion stability. The multi-component synergistic system not only greatly improves the combustion efficiency of the marine fuel oil, but also effectively inhibits harmful substance emission, significantly reduces engine carbon deposition and wear, and maintains the cleanliness of the fuel system. In actual application, the synergist exhibits excellent environmental protection benefits and economic benefits, and provides a green fuel solution for the ship industry, which can not only meet the increasingly stringent environmental protection regulation requirements, but also reduce operation costs.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fuel oil additives, and particularly provides a marine fuel oil cleaning synergist and a preparation method thereof. BACKGROUND

[0002] Currently, the combustion efficiency optimization, particulate matter emission reduction and sulfide control of the fuel oil of a ship power system have higher requirements. However, the existing marine fuel oil and additive technology faces the following key challenges:

[0003] 1. Insufficient control of sulfide emissions: when high-sulfur residual fuel oil (sulfur content 2.5%~3.5%) is burned, the sulfur element is easily converted into sulfate particulate matter (PM 2.5 )(accounting for >8wt%) and hydrogen sulfide (H2S)(concentration in tail gas >50ppm), resulting in catalyst deactivation (sulfur poisoning rate >0.3% / 100h) of the SCR (selective catalytic reduction) aftertreatment system, and at the same time, increasing the risk of ship tail gas SOx emission exceeding the standard.

[0004] 2. Contradiction between combustion efficiency and soot: the high viscosity characteristics (50℃ kinematic viscosity >180cSt) of the fuel oil result in large atomization particle size (D90>50μm), the local oxygen-deficient area in the combustion chamber is enlarged, the soot generation amount reaches 0.15~0.2g / kWh (exceeding the Tier III limit value by more than 50%), the unburned hydrocarbon (UHC) emission increases by 3%~5%, and the thermal efficiency loss is >4%.

[0005] 3. Dispersion stability and oxidation decay problems: the asphaltene and resin content in the fuel oil is high (>8wt%), and the colloidal aggregation (Zeta potential <25mV) easily occurs during storage and combustion, resulting in the sedimentation and separation of the effective components of the additive (centrifugal stability <48h); at the same time, the free radical chain reaction generated by high-temperature oxidation makes the oil oxidation induction period <60min (ASTM D6186), and accelerates the generation of carbon deposition precursors (sediments >15mg / kg).

[0006] Although the existing additive technology improves the combustion efficiency through metal-based catalysts, it has the following limitations: 1. Sulfur-efficiency contradiction: the traditional calcium / magnesium-based detergent reacts with sulfur to generate CaSO4 / MgSO4hard deposits (particle size >10μm), which block the orifice diameter of the fuel injector (pressure difference increases >0.2MPa / 100h); 2. Dispersion failure: a single polyisobutylene amine (PIBA) dispersant cannot maintain the stability of micelles (HLB value mismatch >3) in a high-viscosity medium, resulting in an inactivation rate of effective components >30%; 3. Oxidation out of control: the free radical capture ability of phenolic antioxidant decreases (oxidation initiation temperature decreases >15℃) in a high-sulfur environment, accelerating the generation of sludge (TAN increases >2mg KOH / g).

[0007] Marine fuel oil detergent synergist as a kind of chemical additive, can improve the combustion characteristics of marine fuel oil, improve the combustion efficiency, reduce pollutant emissions, including sulfur oxide (SOx), nitrogen oxide (NOx) and particulate matter (PM) etc. These additives change the chemical structure of fuel, promote more complete combustion process, thereby reducing the emission of unburned fuel, reduce the production of greenhouse gases. Fuel oil detergent synergistic technology is the general term of fuel additive innovation technology with oil saving, emission reduction, carbon reduction, and synergism is oil saving, emission reduction, carbon reduction.

[0008] The existing detergent synergist still faces the problem of multi-target synergistic failure, for example:

[0009] 1. Function antagonism: combustion promoting components (such as metal organic compounds) and sulfur inhibitors (such as molybdate) are prone to precipitation reaction (precipitation rate > 20%) when compounded, resulting in loss of effective ingredients; 2. Insufficient dynamic stability: the synergistic effect of dispersants and antioxidants in high viscosity fuel oil is limited by the difference in interfacial tension (Δγ>5mN / m), and the performance decay is >40% after long-term storage; 3. Low sulfur conversion inhibition efficiency: the adsorption capacity of traditional sulfur capture agent (such as zinc oxide) for H2S is <50mg / g, and the desorption rate is >30% at high temperature, which cannot meet the requirement of >85% for sulfur oxide comprehensive emission reduction rate.

[0010] Therefore, it is urgent to develop a multifunctional additive that can synergistically improve combustion efficiency, inhibit sulfur form conversion, enhance dispersion stability in high viscosity system and delay oxidative decay, to meet the urgent needs of low-carbon and clean transformation of the shipping industry, for example.

[0011] In view of this, the present application is proposed. SUMMARY

[0012] One of the purposes of the present application is to provide a marine fuel oil detergent synergist and a preparation method thereof, to alleviate the problems of low sulfur emission reduction efficiency, prominent combustion soot contradiction, poor dispersion stability and multi-component synergistic failure of the prior art detergent synergist.

[0013] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0014] A marine fuel oil detergent synergist, by mass percentage, the marine fuel oil detergent synergist comprises the following components: 8% to 12% sulfur capture agent, 15% to 20% core-shell dispersant, 5% to 8% lubricant, 0.5% to 1% antioxidant and 1% to 2% pour point depressant, the balance is solvent;

[0015] The sulfur capture agent is a Zr-Mg complex, which realizes sulfur selective adsorption through Zr-O-Mg active sites;

[0016] The core-shell dispersant is a PIBSI-polyether amine core-shell crosslinking material, wherein PIBSI is the inner core and polyether amine is the outer shell.

[0017] The lubricant is boronated glyceride.

[0018] Further, the sulfur capture agent is Zr 4+ -MgO complex, and optionally, the sulfur capture agent is a Zr(NO3)4-MgO complex;

[0019] Optionally, the sulfur adsorption capacity of the sulfur capture agent is not less than 15 mg S / g.

[0020] Optionally, the thermal weight loss of the PIBSI-polyether amine core-shell crosslinking material under high temperature conditions of 300°C is not more than 5%.

[0021] Optionally, the boron content of the boronated glyceride is in the range of 3.5wt%-4.0wt%.

[0022] Further, the antioxidant is alkylated diphenylamine.

[0023] Optionally, the oxidation induction period of the antioxidant under the condition of 150°C is not less than 120 minutes.

[0024] Optionally, the pour point depressant is a polymethacrylate with a molecular weight of 8000.

[0025] Optionally, the pour point depressant reduces the freezing point of the fuel oil by more than 15°C.

[0026] Further, the solvent is a mixed solution of hydrogenated terphenyl and nitroethane.

[0027] Optionally, the proportion of nitroethane in the solvent is 15vol%-30vol%.

[0028] Optionally, the flash point of the solvent is not less than 62°C.

[0029] The preparation method of the above-mentioned marine fuel oil detergent synergist, the solvent is heated to 40-60°C, the antioxidant is added and mixed, then the lubricant and the core-shell dispersant are sequentially added and mixed, and then the sulfur capture agent and the pour point depressant are sequentially added, and the mixture is mixed by using a high-pressure homogenizer of 40-52 MPa to obtain the marine fuel oil detergent synergist.

[0030] Further, the preparation method comprises the following steps:

[0031] S1 premixing stage: the solvent is heated to 45-50℃, the antioxidant is added and stirred to dissolve, then the lubricant is added at 45-50℃, 800-900rpm stirring for 30 minutes, then the core-shell dispersant is added at 55-60℃, 1200-1300rpm stirring for 1 hour;

[0032] S2 final mixing and homogenization stage: slowly add the sulfur capture agent, disperse for 30 minutes by 30-40kHz ultrasonic assistance, then add the pour point depressant at 35-40℃ and mix for 30 minutes, finally cycle through the high pressure homogenizer at 45-50MPa for 3 times.

[0033] Further, under the condition of pH 6.3-6.7, the modified nano-MgO and zirconium nitrate undergo a complex reaction, and the sulfur capture agent is separated and dried;

[0034] Optionally, the complex reaction conditions are 50-70℃ for 1.5-2.5 hours, and the molar ratio of Zr to Mg is 1:2-1:3;

[0035] Optionally, the modifier of nano-MgO is silane coupling agent KH-550;

[0036] Optionally, the modification conditions are 50-80℃ for 1.5-2.5 hours;

[0037] Optionally, the particle size of nano-MgO is 50-70nm.

[0038] Further, the preparation method of the core-shell dispersant comprises:

[0039] (a) PIBSI mother core synthesis stage: PIBSA reacts with polyamine under the condition of inert gas with acid value not more than 2mg KOH / g, and the PIBSI mother core is obtained by drying;

[0040] (b) polyether amine grafting stage: the PIBSI mother core in (a) reacts with polyether amine in a catalyst, and the core-shell dispersant is obtained by removing unreacted monomers;

[0041] Optionally, the polyamine in (a) is TEPA, and the reaction conditions are 80-130℃ for 3-4 hours, and the moisture content of the PIBSI mother core is ≤0.5%;

[0042] Optionally, the catalyst in (b) is at least one of 0.08wt%-0.1wt% dibutyltin dilaurate, 0.05wt% stannous octoate and 0.02wt% p-toluenesulfonic acid, and the reaction conditions are 140-170℃ for 3-4 hours.

[0043] Further, the boric acid and glycerol are reacted at a molar ratio of 1:3-1:3.5 under nitrogen protection at 120-160℃ for 5-6 hours to obtain the lubricant.

[0044] The method for using the marine fuel oil detergent synergist comprises: the marine fuel oil is light diesel oil, and the mass ratio of the detergent synergist to the light diesel oil is 1:1600-1:1400

[0045] Or, the marine fuel oil is low-sulfur oil (LSFO, 0.5% or less), and the mass ratio of the detergent synergist to the low-sulfur oil is 1:1400-1:1200;

[0046] Or, the marine fuel oil is high-sulfur oil (HSFO, 3.5% or more), and the mass ratio of the detergent synergist to the high-sulfur oil is 1:1200-1:1000.

[0047] Compared with the prior art, the technical effects of the present application are:

[0048] The present application provides a marine fuel oil detergent synergist, which has the advantages of high flash point, sulfur inhibition, combustion enhancement and dispersion stability. Through the synergistic effect of the innovative composite metal sulfur capture agent, the dispersant with core-shell structure and the special lubricant, the comprehensive performance of the fuel oil is significantly improved. The marine fuel oil detergent synergist adopts a unique formula design, in which the sulfur capture agent uses the Zr-O-Mg active site to efficiently remove sulfides through the dual mechanisms of chemical adsorption and physical adsorption; the core-shell dispersant ensures the stable dispersion of the synergist under high temperature conditions through the dual action of core anchoring and shell steric hindrance; and the special lubricant forms a self-repairing protective film with the metal surface of the sulfur capture agent. This multi-component synergistic system not only significantly improves the combustion efficiency of the fuel oil, but also effectively inhibits harmful substance emissions, significantly reduces engine carbon deposition and wear, and maintains the cleanliness of the fuel system. In practical applications, the synergist exhibits excellent environmental and economic benefits, is suitable for the combustion of high-sulfur fuel oil, especially in the shipping industry, and provides a green fuel solution that not only meets the increasingly stringent environmental regulations, but also reduces operating costs for the shipping industry, and has a broad market application prospect.

[0049] The preparation method of the marine fuel oil detergent synergist provided by the present application innovatively controls the reaction conditions and key parameters to ensure the stability and reliability of the product performance. DETAILED DESCRIPTION

[0050] In order to enable those skilled in the art to better understand the technical solutions of the present application, the technical solutions described in the present application will be further described in detail below in combination with specific embodiments.

[0051] In the present application, "further", "furthermore", "in particular" and the like are used to describe purposes and represent differences in content, but should not be understood as limiting the scope of protection of the present application.

[0052] In the present application, "optionally", "optional" and "optional" mean optional, that is, selected from any one of the two parallel schemes of "yes" or "no". If there are multiple "options" in a technical solution, unless otherwise specified, and there is no contradictory or mutual restrictive relationship, each "option" is independent.

[0053] In the present application, "multiple", "multiple", "multiple", "multiple" and the like are used, unless otherwise specified, which means more than 2 or equal to 2 in quantity. For example, "one or more" means one or more than two.

[0054] The present application provides a marine fuel oil detergent synergist, which comprises the following components in percentage by mass: 8-12% sulfur capture agent, 15-20% core-shell dispersant, 5-8% lubricant, 0.5-1% antioxidant and 1-2% pour point depressant, and the balance is solvent; the sulfur capture agent is a Zr-Mg complex, which realizes selective adsorption of sulfur through Zr-O-Mg active sites; the core-shell dispersant is a PIBSI-polyether amine core-shell crosslinking material, wherein PIBSI is the inner core and polyether amine is the outer shell; and the lubricant is boronized glycerol ester.

[0055] The content of the sulfur capture agent can be, but is not limited to, 8%, 9%, 10%, 11% or 12%; the content of the core-shell dispersant can be, but is not limited to, 15%, 16%, 17%, 18%, 19% or 20%; the content of the lubricant can be, but is not limited to, 5%, 6%, 7% or 8%; the content of the antioxidant can be, but is not limited to, 0.5%, 0.6%, 0.7%, 0.8%, 0.9% or 1%; and the content of the pour point depressant can be, but is not limited to, 1%, 1.2%, 1.4%, 1.6%, 1.8% or 2%.

[0056] The sulfur capture agent of the present application is a Zr-Mg bimetallic complex, which forms a Zr-O-Mg active site with the surface hydroxyl group of MgO, significantly improving the selectivity of sulfur adsorption. 4+

[0057] The core-shell dispersant of the present application adopts a PIBSI-polyether amine core-shell structure, and the polyether amine shell forms steric hindrance at high temperature, and the PIBSI inner core realizes a double stabilization mechanism through polar anchoring.

[0058] The lubricant of the present application is boronized glycerol ester, which coordinates with the surface oxygen vacancies of the Zr-Mg complex through B-O-C bonds to form a self-repairing lubricating film, greatly improving the lubricating performance. ​

[0059] The marine fuel oil detergent synergist provided by the application realizes deep reduction of sulfur oxide, improvement of combustion efficiency, reduction of carbon smoke emission, and strengthening of stability through synergistic effect of composite catalysis, dispersion, and antioxidant system, eliminates antagonistic effect of functional components, meets dual requirements of fuel oil cleaning and low carbonization, and is particularly suitable for fuel oil cleaning and low carbonization of ships.

[0060] In some embodiments, the sulfur capture agent is a Zr 4+ -MgO complex, optionally a Zr(NO3)4-MgO complex, and optionally, the sulfur adsorption capacity of the sulfur capture agent is not less than 15 mg S / g.

[0061] In some embodiments, the PIBSI-polyether amine core-shell crosslinker has a thermal weight loss of not more than 5% under high-temperature conditions of 300 ℃.

[0062] In some embodiments, the boron content of the boronated glyceride is in the range of 3.5 wt% to 4.0 wt%.

[0063] In some embodiments, the antioxidant is an alkylated diphenylamine; and optionally, the antioxidant has an oxidation induction period of not less than 120 minutes under conditions of 150 ℃.

[0064] In some embodiments, the pour point depressant is a polymethacrylate with a molecular weight of 8000; and optionally, the pour point depressant reduces the freezing point of the fuel oil by more than 15 ℃.

[0065] In some embodiments, the solvent is a mixed solution of hydrogenated terphenyl and nitroethane; and optionally, the nitroethane accounts for 15 vol% to 30 vol% in the solvent; and optionally, the flash point of the solvent is not less than 62 ℃.

[0066] The application provides a preparation method of the above-mentioned marine fuel oil detergent synergist, wherein the solvent is heated to 40-60 ℃, the antioxidant is added and mixed, then the lubricant and the core-shell dispersant are sequentially added and mixed, and then the sulfur capture agent and the pour point depressant are sequentially added, and the mixture is mixed by using a high-pressure homogenizer with a pressure of 40-52 MPa to obtain the marine fuel oil detergent synergist.

[0067] In some embodiments, the preparation method comprises the following steps:

[0068] S1 pre-mixing stage: the solvent is heated to 45-50 ℃, the antioxidant is added and stirred to dissolve, then the lubricant is added at 45-50 ℃ and stirred at 800-900 rpm for 30 minutes, and then the core-shell dispersant is added at 55-60 ℃ and stirred at 1200-1300 rpm for 1 hour;

[0069] S2 final mixing and homogenization stage: slowly add the sulfur capture agent, disperse for 30 minutes with the aid of 30-40 kHz ultrasound, then add the pour point depressant and mix for 30 minutes at 35-40 °C, and finally pass through a high-pressure homogenizer at 40-50 MPa for 3 cycles.

[0070] In some embodiments, the method of preparing the sulfur capture agent comprises:

[0071] MgO modification: mix nano-MgO (e.g. 50 nm particle size) with silane coupling agent KH-550 at a mass ratio of 100:1, and modify at 80 °C for 2 hours.

[0072] Composite reaction stage: slowly add the zirconium nitrate solution to the modified MgO suspension (ethanol medium) at a molar ratio of Zr:Mg = 1:2, react at a constant temperature of 60 °C for 2 hours, and adjust the pH to 6.5 ± 0.2 with ammonia. After the reaction is complete, centrifuge (8000 rpm for 10 minutes) and dry at 80 °C under vacuum for 12 hours.

[0073] Alternatively, MgO modification: ultrasonically disperse nano-MgO (50 nm) with KH-550 (mass ratio 100:1) in ethanol for 30 minutes, and then modify at 80 °C under reflux conditions for 1.5 hours.

[0074] Composite reaction stage: slowly add the zirconium nitrate solution to the modified MgO suspension (containing 0.1% polyvinylpyrrolidone dispersant) at a molar ratio of Zr:Mg = 1:2, react at 60 °C with the aid of ultrasound (40 kHz) for 1.5 hours, and adjust the pH to 6.5 ± 0.2 with ammonia. After centrifugation (8000 rpm for 10 minutes), dry at 80 °C under vacuum for 10 hours.

[0075] Alternatively, MgO modification: ultrasonically disperse nano-MgO (50 nm) with KH-550 (mass ratio 100:1) in ethanol for 30 minutes, and then modify at 80 °C under reflux conditions for 1.5 hours.

[0076] Composite reaction stage: co-precipitate the zirconium nitrate solution with the modified MgO suspension (Zr:Mg = 1:2) at 50 °C, control the pH to 6.5 ± 0.2 with ammonia, and then warm to 70 °C for 1 hour of maturation. After centrifugation (10000 rpm for 8 minutes), use stepwise drying (pre-dry at 60 °C for 2 hours, and then dry at 80 °C under vacuum for 8 hours).

[0077] In some embodiments, the method of preparing the core-shell dispersant comprises:

[0078] PIBSI (polyisobutylene succinimide) core synthesis: PIBSA (molecular weight 950) and TEPA were charged into a reactor under nitrogen protection at a molar ratio of 1:1.2 and reacted at 120°C for 4 hours, with the acid value being monitored in real time until it was less than or equal to 2 mgKOH / g. The product was purified by acetone precipitation three times and vacuum dried until the moisture content was less than or equal to 0.5%.

[0079] Polyether amine grafting: PIBSI was mixed with an ethylene oxide / propylene oxide copolymer (polyether polyol) (EO:PO = 3:1, molecular weight 1000) at a mass ratio of 1:0.8 to 1:1.1, 0.1 wt% dibutyl tin dilaurate catalyst was added, and the mixture was reacted at 150 to 160°C for 3 hours, and finally unreacted monomers were removed by thin film evaporation.

[0080] Alternatively, core synthesis: PIBSA and TEPA (1:1.2 molar ratio) were first pre-reacted at 100°C for 1 hour (to promote ring opening) and then the temperature was raised to 130°C for 3 hours (condensation stage) under nitrogen protection, with the acid value being less than or equal to 2 mgKOH / g. The product was purified by ultrasonic-assisted acetone precipitation (40 kHz, 20 minutes) twice and vacuum dried at 70°C until the moisture content was less than or equal to 0.3%.

[0081] Polyether amine grafting: PIBSI was mixed with an EO / PO copolymer (1:1.1 mass ratio) under the catalysis of 0.05 wt% stannous octoate, and the mixture was reacted in stages: 140°C for 1 hour (start-up), and 160°C for 2 hours (deepening). After grafting, the product was purified by molecular distillation (180°C, 0.1 kPa), with the residual monomer content being less than 0.2%.

[0082] Alternatively, core synthesis: PIBSA and TEPA (1:1.2 molar ratio) were first pre-reacted at 100°C for 1 hour (to promote ring opening) and then the temperature was raised to 130°C for 3 hours (condensation stage) under nitrogen protection, with the acid value being less than or equal to 2 mgKOH / g. The product was purified by ultrasonic-assisted acetone precipitation (40 kHz, 20 minutes) twice and vacuum dried at 70°C until the moisture content was less than or equal to 0.3%.

[0083] Polyether amine grafting: Catalytic system optimization: 0.08 wt% dibutyl tin dilaurate + 0.02 wt% p-toluene sulfonic acid composite catalyst. Gradient grafting: PIBSI was mixed with an EO / PO copolymer (1:1 mass ratio) and reacted at 140°C for 1 hour (initiation of grafting), and at 160°C for 2 hours (completion of chain extension), and finally at 170°C for 0.5 hours (devolatilization). Two-stage thin film evaporation (first stage: 120°C / 10 kPa, second stage: 150°C / 0.5 kPa), with the residual monomer content being less than 0.1%.

[0084] Polyether amine is a terminal amine polymer prepared by amination of an ethylene oxide / propylene oxide copolymer (polyether polyol).

[0085] In some embodiments, the method for preparing the lubricant comprises:

[0086] Boric acid and glycerol are added to a reactor at a molar ratio of 1:3 to 1:3.5, and reacted at 150-160°C under nitrogen protection for 5-6 hours. The boron content is detected by sampling every hour. After the reaction is completed, water is removed by reduced pressure distillation (-0.095 MPa, 80°C).

[0087] Alternatively, boric acid and glycerol (1:3 molar ratio) are mixed, and 0.5 wt% of p-toluenesulfonic acid catalyst is added. The reaction is carried out at 140°C by toluene azeotropic dehydration (oil-water separator reflux), and the reaction time is shortened to 4 hours. Post-processing: toluene is first removed by atmospheric distillation (110°C), and then refined by reduced pressure distillation (-0.098 MPa, 70°C). Product specifications: esterification rate 88%-91%, water residue 0.3%-0.5%, catalyst residue <200 ppm.

[0088] Alternatively, gradient reaction: Stage 1: boric acid and glycerol (1:3 molar ratio) are pre-mixed at 120°C for 1 hour (to promote dissolution). Stage 2: the temperature is raised to 150°C and reacted for 3 hours, while dry nitrogen is introduced (0.2 L / min) and a 4A molecular sieve column is used for dynamic dehydration. Post-processing: two-stage reduced pressure distillation (first stage -0.090 MPa / 60°C to remove light components, second stage -0.100 MPa / 75°C for refining). Product specifications: esterification rate 93%-95%, water residue ≤0.1%, no risk of catalyst residue.

[0089] The application provides a method for using the above-mentioned marine fuel oil detergent synergist, which comprises: the marine fuel oil is light diesel oil, and the mass ratio of the detergent synergist to the light diesel oil is 1:1600-1:1400;

[0090] Alternatively, the marine fuel oil is low-sulfur oil (LSFO, below 0.5%), and the mass ratio of the detergent synergist to the low-sulfur oil is 1:1400-1:1200;

[0091] Alternatively, the marine fuel oil is high-sulfur oil (HSFO, above 3.5%), and the mass ratio of the detergent synergist to the high-sulfur oil is 1:1200-1:1000.

[0092] The application will be further described below in conjunction with specific embodiments. The advantages and characteristics of the application will become clear with the description. The embodiments are only exemplary and do not constitute any limitation on the scope of the application. Those skilled in the art should understand that the details and forms of the technical solutions of the application can be modified or replaced without departing from the spirit and scope of the application, and such modifications and replacements fall within the protection scope of the application.

[0093] The chemical reagents used in the embodiments of the present application are all of analytical purity, purchased from the National Pharmaceutical Group.

[0094] To make the present application easier to understand, the following further describes the present application in conjunction with specific embodiments. The experimental methods described in the present application are all conventional methods if not otherwise specified; the biological materials described in the present application are all commercially available if not otherwise specified.

[0095] Example 1 Sulfur capture agent

[0096] Scheme 1: Conventional modification method - MgO modification: nano-MgO (particle size 50 nm) was directly mixed with silane coupling agent KH-550 at a mass ratio of 100:1, and modified at 80°C under mechanical stirring for 2 hours. Composite reaction stage: zirconium nitrate solution was added dropwise to the ethanol suspension of modified MgO at a molar ratio of Zr:Mg = 1:2, and reacted at 60°C for 2 hours, and the pH was adjusted to 6.5±0.2 with ammonia water. After the reaction, centrifugation (8000 rpm, 10 minutes) was performed, and vacuum drying was performed at 80°C for 12 hours.

[0097] Scheme 2: Ultrasonic-assisted modification method - MgO modification: nano-MgO (50 nm) was ultrasonically dispersed in ethanol with KH-550 (mass ratio 100:1) for 30 minutes, and then modified at 80°C under reflux conditions for 1.5 hours. Composite reaction stage: zirconium nitrate solution was slowly added to the modified MgO suspension (containing 0.1% polyvinylpyrrolidone dispersant) at a molar ratio of Zr:Mg = 1:2, and reacted at 60°C under ultrasonic assistance (40 kHz) for 1.5 hours, and the pH was adjusted to 6.5±0.2 with ammonia water. After centrifugation (8000 rpm, 10 minutes), vacuum drying was performed at 80°C for 10 hours.

[0098] Scheme 3: Gradient temperature-co-precipitation method (recommended optimal scheme) - MgO modification: nano-MgO (50 nm) was first pre-reacted with KH-550 (mass ratio 100:1) in ethanol at 50°C for 1 hour (to promote coupling agent adsorption), and then modified at 80°C for 1 hour (to complete the condensation reaction). Composite reaction stage: zirconium nitrate solution was co-precipitated with the modified MgO suspension (Zr:Mg = 1:2) at 50°C, and the pH was controlled to 6.5±0.2 with ammonia water, and then the temperature was increased to 70°C for 1 hour of maturation. After centrifugation (10000 rpm, 8 minutes) of the reaction liquid, stepwise drying was performed (pre-drying at 60°C for 2 hours, and then vacuum drying at 80°C for 8 hours).

[0099] The gradient temperature method promotes the hydrolysis and condensation of silane coupling agents in stages, and the grafting rate is increased by 15% to 20% compared with the conventional method (Scheme 1). The product of Scheme 3 has a significant improvement in adsorption capacity, reaching 85 mg / g in the sulfur capacity test at 200°C, which is significantly higher than that of Scheme 1 (68 mg / g) and Scheme 2 (62 mg / g).

[0100] Example 2 Core-shell dispersant

[0101] Scheme 1 : Conventional synthesis - Nucleus synthesis: PIBSA (Mw 950) and TEPA were charged into a reaction kettle under nitrogen protection at a molar ratio of 1 : 1.2, and reacted at 120°C for 4 hours, with the acid value being monitored to be ≤2 mgKOH / g. The product was purified by acetone precipitation for 3 times, and vacuum dried at 80°C to moisture ≤0.5%. Polyether amine grafting: PIBSI was mixed with EO / PO copolymer (EO:PO = 3:1, Mw 1000) at a mass ratio of 1 : 1, 0.1 wt% dibutyl tin dilaurate was added, and reacted at 150°C for 3 hours, with thin film evaporation being used to remove unreacted monomers.

[0102] Scheme 2: Temperature control in stages - ultrasonic-assisted method - Nucleus synthesis: PIBSA and TEPA (1 : 1.2 molar ratio) were first pre-reacted at 100°C for 1 hour (to promote ring opening) under nitrogen protection, and then the temperature was raised to 130°C for 3 hours (condensation stage), with the acid value being ≤2 mgKOH / g. Ultrasonic-assisted acetone precipitation (40 kHz, 20 minutes) was used for purification for 2 times, and vacuum drying was performed at 70°C to moisture ≤0.3%. Polyether amine grafting: PIBSI was mixed with EO / PO copolymer (1 : 1.1 mass ratio) under the catalysis of 0.05 wt% stannous octoate, and reacted in stages: 140°C for 1 hour, and 160°C for 2 hours. After grafting, purification was performed by molecular distillation (180°C, 0.1 kPa), with the residual monomer content being <0.2%.

[0103] Scheme 3: Catalytic optimization - gradient grafting method (recommended optimal scheme) - Nucleus synthesis: PIBSA and TEPA (1 : 1.2 molar ratio) were subjected to stepwise temperature increase under nitrogen protection: 80°C (0.5 hours, pre-mixing) → 110°C (2 hours, amidation) → 125°C (1.5 hours, dehydration and ring closure), with the acid value being ≤1.5 mgKOH / g. Purification was performed by acetone / n-hexane (1 : 1) mixed solvent precipitation for 2 times, and vacuum drying was performed at 60°C to moisture ≤0.2%. Polyether amine grafting: Catalytic system optimization: 0.08 wt% dibutyl tin dilaurate + 0.02 wt% p-toluene sulfonic acid composite catalysis. Gradient grafting: PIBSI was mixed with EO / PO copolymer (1 : 1 mass ratio) at 140°C for 1 hour (to initiate grafting), and reacted at 160°C for 2 hours (to complete chain extension), and finally 170°C for 0.5 hours (to remove volatiles). Two-stage thin film evaporation (first stage 120°C / 10 kPa, second stage 150°C / 0.5 kPa) was used, with the monomer residue being <0.1%.

[0104] Scheme 3 is more suitable for scale-up production by controlling reaction rate and side reaction through temperature gradient and composite catalysis. The dispersibility test shows that the diesel detergency (nozzle deposit) of the product of Scheme 3 is 15% lower than that of Scheme 1. The catalytic optimization-gradient grafting method (Scheme 3) performs best in reaction control, product purity and application performance, and is recommended as the preferred scheme for industrial production.

[0105] Example 3 lubricant

[0106] Scheme 1: conventional esterification method - esterification reaction: boric acid and glycerol are added to the reaction kettle at a molar ratio of 1:3, and reacted at 160°C under nitrogen protection for 6 hours. The boric acid content is detected (titration method) every hour. Post-processing: after the reaction is completed, remove the water under reduced pressure at -0.095 MPa and 80°C for 2 hours. Product index: esterification rate 82%-85%, water residue 0.8%-1.2%.

[0107] Scheme 2: catalytic esterification - after mixing boric acid and glycerol (1:3 molar ratio), 0.5wt% p-toluene sulfonic acid catalyst is added. The reaction is carried out at 140°C by toluene azeotropic dehydration (oil-water separator reflux), and the reaction time is shortened to 4 hours. Post-processing: first remove the toluene at normal pressure (110°C), then distill under reduced pressure (-0.098 MPa, 70°C) for purification. Product index: esterification rate 88%-91%, water residue 0.3%-0.5%, catalyst residue <200ppm.

[0108] Scheme 3: gradient temperature-molecular sieve dehydration method (recommended optimal scheme) - gradient reaction: stage 1: boric acid and glycerol (1:3 molar ratio) are pre-mixed at 120°C for 1 hour (to promote dissolution). Stage 2: temperature is raised to 150°C for 3 hours, dry nitrogen is introduced (0.2 L / min) and 4A molecular sieve column is connected in series for dynamic dehydration. Post-processing: two-stage reduced pressure distillation (first stage -0.090 MPa / 60°C to remove light components, second stage -0.100 MPa / 75°C for purification). Product index: esterification rate 93%-95%, water residue ≤0.1%, no catalyst residue risk.

[0109] Dynamic dehydration of molecular sieve increases the esterification rate to 95% (more than 10% higher than Scheme 1).

[0110] Example 4 marine fuel oil detergent synergist

[0111] Preparation of different ratio synergists: adjust the ratio of each component (sulfur capture agent, core-shell dispersant, lubricant, antioxidant, pour point depressant, solvent) and observe its effect on performance.

[0112] Example ratio range:

[0113] Sulfur scavenger: 8-12% (Zr-Mg complex, sulfur adsorption > 15 mg S / g); core-shell dispersant: 15-20% (PIBSI-polyetheramine core-shell crosslinker, thermal weight loss < 5% at 300°C); lubricant: 5-8% (boronated glycerol ester, boron content 3.5-4.0%); antioxidant: 0.5-1% (alkylated diphenylamine, oxidation induction time > 120 min at 150°C); pour point depressant: 1-2% (polymethacrylate, pour point reduction > 15°C); solvent: balance (hydrogenated terphenyl + 15-30% nitroethane, flash point > 62°C)

[0114] Performance test indicators

[0115] Flash point: to ensure the safety of the solvent (> 62°C); sulfur inhibition efficiency: evaluated by the adsorption capacity of the sulfur scavenger (> 15 mg S / g); combustion efficiency: test the soot emission reduction rate and the change of combustion heat value; atomization performance: the influence of the core-shell dispersant on the uniformity of fuel oil atomization; oxidation resistance: the oxidation induction time of the antioxidant at high temperature (150°C) (> 120 min); anti-wear property: the protection effect of the lubricant (boronated glycerol ester) on engine parts.

[0116] Example design

[0117] Scheme 1 (low sulfur oil):

[0118] Sulfur scavenger of scheme 3 of example 1 10%, core-shell dispersant of scheme 3 of example 2 18%, lubricant of scheme 3 of example 3 6%, alkylated diphenylamine 0.8%, polymethacrylate 1.5%, and the balance is 70 vol% hydrogenated terphenyl and 30 vol% nitroethane. Suitable for low-sulfur fuel oil (LSFO, 0.5% sulfur), the addition ratio is 1:1400.

[0119] Scheme 2 (high sulfur oil):

[0120] Sulfur scavenger of scheme 3 of example 1 12%, core-shell dispersant of scheme 3 of example 2 20%, lubricant of scheme 3 of example 3 5%, alkylated diphenylamine 1%, polymethacrylate 2%, and the balance is 70 vol% hydrogenated terphenyl and 30 vol% nitroethane. Suitable for high-sulfur fuel oil (HSFO, 3.5% sulfur), the addition ratio is 1:1000.

[0121] Scheme 3 (light diesel):

[0122] Sulfur scavenger of scheme 3 of example 1 8%, core-shell dispersant of scheme 3 of example 2 15%, lubricant of scheme 3 of example 3 8%, alkylated diphenylamine 0.5%, polymethacrylate 1%, and the balance is 70 vol% hydrogenated terphenyl and 30 vol% nitroethane. Suitable for light diesel, the addition ratio is 1:1600.

[0123] Scheme 4 (low sulfur oil):

[0124] Sulfur scavenger 10% of Scheme 1 of Example 1, core-shell dispersant 18% of Scheme 1 of Example 2, lubricant 6% of Scheme 1 of Example 3, alkylated diphenylamine 0.8%, polymethacrylate 1.5%, the balance being 70 vol% hydrogenated terphenyl and 30 vol% nitroethane. Suitable for medium-low sulfur fuel oil (LSFO, 0.5% sulfur), addition ratio 1:1400.

[0125] Scheme 5 (low sulfur oil):

[0126] Sulfur scavenger 10% of Scheme 2 of Example 1, core-shell dispersant 18% of Scheme 2 of Example 2, lubricant 6% of Scheme 2 of Example 3, alkylated diphenylamine 0.8%, polymethacrylate 1.5%, the balance being 70 vol% hydrogenated terphenyl and 30 vol% nitroethane. Suitable for medium-low sulfur fuel oil (LSFO, 0.5% sulfur), addition ratio 1:1400.

[0127] Preparation process of Scheme 1-Scheme 5:

[0128] S1 Pre-mixing stage: heat the solvent to 45-50°C, add the antioxidant and stir to dissolve, then add the lubricant at 45-50°C, stir at 800-900 rpm for 30 minutes, then add the core-shell dispersant at 55-60°C, stir at 1200-1300 rpm for 1 hour;

[0129] S2 Final mixing and homogenization stage: slowly add the sulfur scavenger, disperse for 30 minutes with the aid of 30-40 kHz ultrasound, then add the pour point depressant and mix at 35-40°C for 30 minutes, and finally pass through a high-pressure homogenizer for 3 cycles at 40-50 MPa.

[0130] Performance test results:

[0131]

[0132] Recommended preferred scheme

[0133] Proportion: sulfur scavenger 10%, core-shell dispersant 18%, lubricant 6%, antioxidant 0.8%, pour point depressant 1.5%. Balanced sulfur inhibition (15 mg S / g), dispersion stability (core-shell structure thermal weight loss ≤5%), and cost-effectiveness, suitable for mainstream sulfur content fuel oil (0.5%-3.5%).

[0134] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. If there is a conflict between the definitions of terms in the specification and the patent statutes, the latter shall control. In addition, the weight of expressions used in the description of the specification will be understood by a person of ordinary skill in the art to be qualified by the context, unless otherwise indicated.

[0135] The term "comprising", used in the context of describing the application, should not be construed as limited to the listed features or steps only; it does not exclude other features or steps. Thus, other features or steps can be added and still be within the scope of the application. Therefore, the term "comprising" should not be interpreted as a statistical limitation.

[0136] It is to be understood that the features mentioned in the one or more embodiments described in the specification can be combined with features of other embodiments mentioned in the specification in any appropriate manner within the scope of the application.

Claims

1. A marine fuel oil detergency enhancer characterized by, The marine fuel oil detergent booster comprises the following components in percentage of mass: 8-12% sulfur capturing agent, 15-20% core-shell dispersant, 5-8% lubricant, 0.5-1% antioxidant and 1-2% pour point depressant, and the rest is solvent; The sulfur capturing agent is a Zr-Mg compound, and sulfur selective adsorption is realized through Zr-O-Mg active sites. The core-shell dispersant is a PIBSI-polyether amine core-shell crosslinking material, wherein PIBSI is the inner core and polyether amine is the outer shell. The lubricant is borated glycerol ester.

2. The marine fuel oil detergent of claim 1 wherein, The sulfur capture agent is Zr 4+ -MgO complex.

3. The marine fuel oil detergent of claim 2 wherein, The sulfur capturing agent is a Zr(NO3)4-MgO compound.

4. The marine fuel oil detergent of claim 2 wherein, The sulfur adsorption capacity of the sulfur capturing agent is not less than 15 mg S / g.

5. The marine fuel oil detergent of claim 1 wherein, The thermal weight loss of the PIBSI-polyether amine core-shell crosslinking material under high temperature conditions of 300℃ is not more than 5%.

6. The marine fuel oil detergent of claim 1 wherein, The boron content of the borated glycerol ester is in the range of 3.5wt%-4.0wt%.

7. The marine fuel oil detergent of claim 1 wherein, The antioxidant is alkylated diphenylamine.

8. The marine fuel oil detergent of claim 7 wherein, The oxidation induction period of the antioxidant at 150℃ is not less than 120 minutes.

9. The marine fuel oil detergent of claim 1 wherein, The pour point depressant is polymethacrylate with a molecular weight of 8000.

10. The marine fuel oil detergent of claim 9 wherein, The pour point depressant reduces the freezing point of fuel oil by more than 15℃.

11. The marine fuel oil detergent of any one of claims 1 to 10, wherein, The solvent is a mixed solution of hydrogenated terphenyl and nitroethane.

12. The marine fuel oil detergent of claim 11 wherein, The proportion of nitroethane in the solvent is 15vol%-30vol%.

13. The marine fuel oil detergent of claim 12 wherein, The flash point of the solvent is not less than 62℃.

14. A process for the preparation of a marine fuel oil detergency enhancer as defined in any one of claims 1 to 13, characterized in that, The solvent is heated to 40-60℃, the antioxidant is added and mixed, then the lubricant and the core-shell dispersant are added and mixed in sequence, and then the sulfur capturing agent and the pour point depressant are added and mixed, and finally the marine fuel oil detergent booster is obtained by using a high-pressure homogenizer with a pressure of 40-52 MPa.

15. The preparation method according to claim 14, characterized in that, The preparation method comprises the following steps: S1 pre-mixing stage: the solvent is heated to 45-50℃, the antioxidant is added and stirred to dissolve, then the lubricant is added at 45-50℃ and stirred at 800-900 rpm for 30 minutes, then the core-shell dispersant is added at 55-60℃ and stirred at 1200-1300 rpm for 1 hour; S2 final mixing and homogenizing stage: the sulfur capturing agent is slowly added, ultrasonic assisted dispersion is carried out for 30-40 minutes, then the pour point depressant is added and mixed at 35-40℃ for 30 minutes, and finally the high-pressure homogenizer is used for cyclic treatment at 40-50 MPa for 3 times.

16. The production method according to claim 14 or 15, characterized by, Under the condition that the pH is 6.3-6.7, the modified nano-MgO and zirconium nitrate are subjected to a complex reaction, and the sulfur capturing agent is obtained by separation and drying.

17. The method of claim 16, wherein, The complex reaction is carried out at 50-70℃ for 1.5-2.5 hours, and the molar ratio of Zr to Mg is 1:2-1:

3.

18. The method of claim 16, wherein, The modifier of nano-MgO is silane coupling agent KH-550.

19. The method of claim 18, wherein, The modification is carried out at 50-80℃ for 1.5-2.5 hours.

20. The method of claim 18, wherein, The particle size of nano-MgO is 50-70 nm.

21. The method of manufacturing according to claim 14 or 15, wherein, The preparation method of the core-shell dispersant comprises: (a) PIBSI parent core synthesis stage: PIBSA is reacted with polyamine under the condition of inert gas with an acid value not more than 2 mg KOH / g, and the PIBSI parent core is obtained by drying; (b) polyether amine grafting stage: reacting the PIBSI nucleus in (a) with polyether amine in a catalyst to remove unreacted monomers to obtain a core-shell dispersant.

22. The method of claim 21, wherein, In (a), the polyamine is TEPA, the reaction condition is 80-130℃ for 3-4 hours, and the water content of the PIBSI nucleus is ≤0.5%.

23. The preparation method according to claim 21, characterized in that, In (b), the catalyst is at least one of 0.08wt%-0.1wt% dibutyl tin dilaurate, 0.05wt% stannous octoate and 0.02wt% p-toluene sulfonic acid, and the reaction condition is 140-170℃ for 3-4 hours.

24. The method of manufacturing according to claim 14 or 15, wherein, The lubricant is obtained by reacting boric acid with glycerol at a molar ratio of 1:3-1:3.5 at 120-160℃ under nitrogen protection for 5-6 hours.

25. A method of using the marine fuel oil detergency enhancer of any one of claims 1 to 13, characterized in that, The use method comprises: the marine fuel oil is light diesel oil, and the mass ratio of the detergent synergist to the light diesel oil is 1:1600-1:1400; Or, the marine fuel oil is LSFO, a low-sulfur oil with a sulfur content of 0.5% or less, and the mass ratio of the detergent synergist to the low-sulfur oil is 1:1400-1:1200; Or, the marine fuel oil is HSFO, a high-sulfur oil with a sulfur content of 3.5% or more, and the mass ratio of the detergent synergist to the high-sulfur oil is 1:1200-1:1000.

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