阅读说明：本技术 一种催化氧化脱硫催化剂催化燃油的方法及其应用 (Method for catalyzing fuel oil by catalytic oxidation desulfurization catalyst and application thereof ) 是由 杨延钊 郝梦 郭松 于 2021-10-26 设计创作，主要内容包括：本发明涉及燃油脱硫技术领域,具体涉及一种催化氧化脱硫催化剂催化燃油的方法及其应用。为了解决现有技术存在的催化含硫量较低的车用燃油效率较低,或者催化效果不明显,因此本发明提出一种催化氧化脱硫催化剂催化燃油的方法及其应用。相较于现有技术中催化1000ppm含硫量的燃油,本发明所公开的催化方法通过在反应中加入乙酸,通过催化剂、乙酸、过氧化氢的配合,实现催化剂对低含硫量燃油的进一步处理。可以催化硫含量为200ppm的车用燃油,催化后硫残余量低至0.4ppm,实现低硫燃油进一步降低硫含量。(The invention relates to the technical field of fuel oil desulfurization, in particular to a method for catalyzing fuel oil by a catalytic oxidation desulfurization catalyst and application thereof. The invention provides a method for catalyzing fuel oil by a catalytic oxidation desulfurization catalyst and application thereof, aiming at solving the problems that the efficiency of catalyzing vehicle fuel oil with low sulfur content is low or the catalysis effect is not obvious in the prior art. Compared with the prior art for catalyzing fuel oil with 1000ppm of sulfur content, the catalytic method disclosed by the invention has the advantages that acetic acid is added in the reaction, and the catalyst is matched with acetic acid and hydrogen peroxide to further treat the fuel oil with low sulfur content. The sulfur-containing vehicle fuel oil can be catalyzed, the residual sulfur content after catalysis is as low as 0.4ppm, and the sulfur content of the low-sulfur fuel oil is further reduced.)

1. A method for catalyzing fuel oil by a catalytic oxidation desulfurization catalyst is characterized by comprising the following steps: mixing porous silicon dioxide and imidazole phosphotungstate, washing and drying to obtain a catalytic oxidation desulfurization catalyst;

mixing the catalytic oxidation desulfurization catalyst with fuel oil, adding acetic acid and hydrogen peroxide, and reacting.

2. The method for catalyzing fuel oil by catalytic oxidation desulfurization catalyst according to claim 1, wherein the acetic acid and the hydrogen peroxide are used in the same amount;

preferably, the molar ratio of the hydrogen peroxide to the acetic acid to the sulfur in the fuel oil is 1-2:1-2: 5-7;

preferably, the molar ratio of the hydrogen peroxide to the acetic acid to the sulfur in the fuel oil is 1:1: 6.

3. The method for catalyzing fuel oil by catalytic oxidation desulfurization catalyst according to claim 1, wherein the preparation method of porous silica comprises: mixing HCl solution of tetraethyl orthosilicate (TEOS) with ethanol, hydrolyzing at constant temperature, heating and evaporating to form gel, drying the gel at constant temperature to obtain white or light yellow powder, and grinding to obtain the product.

4. The method for catalyzing fuel oil by catalytic oxidation desulfurization catalyst according to claim 1, wherein the method for preparing the catalytic oxidation desulfurization catalyst comprises: adding the imidazole salt aqueous solution into the porous silica suspension, mixing, adding the phosphotungstic acid aqueous solution to generate a precipitate, and filtering, washing and drying the precipitate to obtain the product;

preferably, the loading rate of the solid heteropoly acid in the catalytic oxidation desulfurization catalyst is 10-50% by mass fraction; preferably 25-30%.

5. The method for catalyzing fuel oil by using the catalytic oxidation desulfurization catalyst according to claim 1, wherein the silica is prepared by the following method:

mixing hydrochloric acid solution of ethyl orthosilicate with ethanol, adjusting pH of the mixed solution to 2-4, hydrolyzing at constant temperature of 40-70 deg.C for 5-9h to generate sol, heating and evaporating to form gel, oven drying the gel at constant temperature of 70-100 deg.C, and grinding.

6. The method for catalyzing fuel oil by using the catalytic oxidation desulfurization catalyst according to claim 1, wherein the imidazolium salt is one selected from 1-butyl-3-methylimidazole bromide salt, 1-hexyl-3-methylimidazole chloride salt, 1-hexyl-3-methylimidazole bromide salt, 1-butyl-3-methylimidazole chloride salt and 1-butyl-3-methylimidazole carboxylate, and the molar ratio of the imidazolium salt to the phosphotungstic acid is 3.05: 1;

preferably, the ratio of the mass of the catalytic oxidation desulfurization catalyst to the volume of the fuel oil is 0.001-0.002g:1mL, preferably 0.001-0.0015g:1 mL.

7. The method for catalyzing fuel oil by using the catalytic oxidative desulfurization catalyst according to claim 1, wherein the organic sulfide in the fuel oil is thiophene sulfide, preferably dibenzothiophene sulfide; preferably, the sulfur content in the fuel oil is 50-200 ppm;

preferably, the weight percentage of the hydrogen peroxide solution is 30 wt%.

8. The method for catalyzing fuel oil by using the catalytic oxidation desulfurization catalyst as recited in claim 1, wherein the reaction temperature is 65-80 ℃ and the reaction time is 90-120 min.

9. The ultra-low sulfur fuel oil prepared by the method for catalyzing fuel oil by catalyzing, oxidizing and desulfurizing catalyst according to any one of claims 1 to 8;

preferably, the sulfur content in the ultra-low sulfur fuel oil is lower than 1.6 ppm;

preferably, the sulfur content of the ultra-low sulfur fuel oil is less than 0.4 ppm.

10. The use of the ultra low sulfur fuel of claim 9 in the fields of vehicles and construction.

Technical Field

The invention relates to the technical field of fuel oil desulfurization, in particular to a method for catalyzing fuel oil by a catalytic oxidation desulfurization catalyst and application thereof.

Background

The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.

The most common industrial desulfurization technique for vehicle fuel oil is hydrodesulfurization, i.e. catalytic hydrogenation of vehicle fuel oil under high temperature and high pressure conditions to convert organic sulfides in the vehicle fuel oil into H₂And S. The technology has remarkable effect on processing oil products with high sulfur content of thousands of ppm on a large scale, but has a larger problem in producing fuel oil for ultra-low sulfur vehicles. For example: thiophene, benzothiophene and Dibenzothiophene (DBT) compounds in the vehicle fuel oil are difficult to remove through catalytic hydrogenation; when the vehicle fuel oil with low sulfur content is treated, the sulfur content is low, so that a catalyst with better catalytic effect is needed for catalysis, and the desulfurization effect is further improved.

Disclosure of Invention

The invention provides a method for catalyzing fuel oil by a catalytic oxidation desulfurization catalyst and application thereof, aiming at solving the problems that the efficiency of catalyzing vehicle fuel oil with low sulfur content is low or the catalysis effect is not obvious in the prior art. Compared with the prior art for catalyzing fuel oil with 1000ppm of sulfur content, the catalytic method disclosed by the invention has the advantages that acetic acid is added in the reaction, and the catalyst is matched with acetic acid and hydrogen peroxide to further treat the fuel oil with low sulfur content. The sulfur-containing vehicle fuel oil can be catalyzed, the residual sulfur content after catalysis is as low as 0.4ppm, and the sulfur content of the low-sulfur fuel oil is further reduced.

Specifically, the invention is realized by the following technical scheme:

in a first aspect of the present invention, a method for catalyzing fuel oil by a catalytic oxidation desulfurization catalyst is provided, which comprises: mixing porous silicon dioxide and imidazole phosphotungstate, washing and drying to obtain a catalytic oxidation desulfurization catalyst;

mixing the catalytic oxidation desulfurization catalyst with fuel oil, adding acetic acid and hydrogen peroxide, and reacting.

In a second aspect of the invention, the ultra-low sulfur fuel oil is prepared by a method for catalyzing fuel oil by a catalytic oxidation desulfurization catalyst.

The third aspect of the invention provides an application of ultra-low sulfur fuel in the fields of vehicles and construction.

One or more of the technical schemes have the following beneficial effects:

1) the acetic acid is added in the reaction, and the catalyst is matched with the acetic acid and the hydrogen peroxide to further treat the fuel oil with low sulfur content. Compared with the conventional catalyst which can only treat fuel oil with the sulfur content of 1000ppm, the catalytic method disclosed by the invention can be used for catalyzing the vehicle fuel oil with the sulfur content of 200ppm, the residual sulfur content after catalysis is as low as 0.4ppm, and the sulfur content of the low-sulfur fuel oil is further reduced.

2) Some schemes of the invention load imidazole phosphotungstate on porous carrier SiO₂Not only can the catalytic activity of the imidazole phosphotungstate be kept, but also the catalyst exists at the interface of oil phase and water phase to adsorb hydrogen peroxide and increase H₂O₂The contact area of the catalyst and sulfide in the vehicle fuel oil greatly improves the use efficiency of the oxidant, and the catalyst is recycled through simple filtration or centrifugation, washed by water and dried for reuse, and the activity reduction of repeated use is not obvious. After the desulfurization reaction is finished, the dibenzothiophene can be removed by simple water washing, and the desulfurized oil product with extremely low sulfur content is obtained without loss basically. The method is simple, mild in operation condition and low in cost, and has great application prospect.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. Embodiments of the invention are described in detail below with reference to the attached drawing figures, wherein:

FIG. 1 is an infrared image of a catalytic oxidative desulfurization catalyst prepared in example 1;

FIG. 2 is a Thermogravimetric (TGA) plot of the catalytic oxidative desulfurization catalyst prepared in example 1, wherein: a-SiO₂(ii) a b-mesoporous SiO₂(ii) a c-a novel catalytic oxidation desulfurization catalyst.

Detailed Description

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The experimental procedures, in which specific conditions are not noted in the following examples, are generally carried out according to conventional conditions or according to conditions recommended by the manufacturers.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The invention provides a method for catalyzing fuel oil by a catalytic oxidation desulfurization catalyst and application thereof, aiming at solving the problems that the efficiency of catalyzing vehicle fuel oil with low sulfur content is low or the catalysis effect is not obvious in the prior art. Compared with the prior art for catalyzing fuel oil with 1000ppm of sulfur content, the catalytic method disclosed by the invention has the advantages that acetic acid is added in the reaction, and the catalyst is matched with acetic acid and hydrogen peroxide to further treat the fuel oil with low sulfur content. The sulfur-containing vehicle fuel oil can be catalyzed, the residual sulfur content after catalysis is as low as 0.4ppm, and the sulfur content of the low-sulfur fuel oil is further reduced.

Specifically, the invention is realized by the following technical scheme:

in a first aspect of the present invention, a method for catalyzing fuel oil by a catalytic oxidation desulfurization catalyst is provided, which comprises: mixing porous silicon dioxide and imidazole phosphotungstate, washing and drying to obtain a catalytic oxidation desulfurization catalyst;

mixing the catalytic oxidation desulfurization catalyst with fuel oil, adding acetic acid and hydrogen peroxide, and reacting.

The reason why the conventional catalyst cannot catalyze and degrade the fuel oil with low sulfur content is that: when the conventional catalyst is used, acetic acid and hydrogen peroxide are not jointly used, the oxidation property of the hydrogen peroxide is weaker than that of peroxyacetic acid formed by the reaction of the hydrogen peroxide and the acetic acid, and simultaneously, because the acetic acid is not introduced, the hydrogen ion content in the desulfurization process is far lower than that of the introduced acetic acid, so the conventional catalyst cannot catalyze and degrade the fuel oil with low sulfur content.

In one or more embodiments of the invention, the acetic acid and hydrogen peroxide are used in the same amount.

The inventor finds that, in addition to the effect that the combination of the catalyst, the acetic acid and the hydrogen peroxide is helpful for further catalyzing the fuel oil with low sulfur content, the ratio of the acetic acid and the hydrogen peroxide also affects the catalysis effect correspondingly. If the amount of acetic acid is too small, the combination of the two cannot be achieved, and if the amount of acetic acid is too large, the catalytic effect of hydrogen peroxide is reduced.

Preferably, the molar ratio of the hydrogen peroxide to the acetic acid to the sulfur in the fuel oil is 1-2:1-2: 5-7;

preferably, the molar ratio of the hydrogen peroxide to the acetic acid to the sulfur in the fuel oil is 1:1: 6.

The concentration of the acetic acid solution is 0.1-0.2 mol/L.

Compared with a scheme of simply researching the mass ratio of raw materials, the more specific embodiments of the invention are beneficial to improving the catalytic effect of the catalyst and maximally realizing the combined effect of the catalyst, acetic acid and hydrogen peroxide.

In one or more embodiments of the present invention, the porous silica preparation method includes: mixing HCl solution of tetraethyl orthosilicate (TEOS) with ethanol, hydrolyzing at constant temperature, heating and evaporating to form gel, drying the gel at constant temperature to obtain white or light yellow powder, and grinding to obtain the product.

In one or more embodiments of the present invention, the method for preparing the catalytic oxidative desulfurization catalyst includes: adding the imidazole salt aqueous solution into the porous silica suspension, mixing, adding the phosphotungstic acid aqueous solution to generate a precipitate, and filtering, washing and drying the precipitate to obtain the product;

in some embodiments, the step of loading the solid heteropolyacid salt using the mixer-settling method is as follows:

porous SiO₂Dissolving in distilled water to form a suspension, slowly dripping the suspension into an imidazole salt solution, stirring for 1-4h at 30-40 ℃, slowly dripping a phosphotungstic acid solution to generate a white precipitate, filtering, washing, and drying for 8-24h at 50-80 ℃ to obtain the silica-supported solid heteropoly acid oxidation desulfurization catalyst.

Preferably, the loading rate of the solid heteropoly acid in the catalytic oxidation desulfurization catalyst is 10-50% by mass fraction; preferably 25-30%.

In one or more embodiments of the invention, the silica is prepared by the following method:

mixing hydrochloric acid solution of ethyl orthosilicate with ethanol, adjusting pH of the mixed solution to 2-4, hydrolyzing at constant temperature of 40-70 deg.C for 5-9h to generate sol, heating and evaporating to form gel, oven drying the gel at constant temperature of 70-100 deg.C, and grinding.

In one or more embodiments of the invention, the imidazolium salt is selected from one of 1-butyl-3-methylimidazole bromide, 1-hexyl-3-methylimidazole chloride, 1-hexyl-3-methylimidazole bromide, 1-butyl-3-methylimidazole chloride or 1-butyl-3-methylimidazole carboxylate, and the molar ratio of the imidazolium salt to the phosphotungstic acid is 3.05: 1.

In one or more embodiments of the invention, the organic sulfide in the fuel oil is a thiophene sulfide, preferably a dibenzothiophene sulfide; preferably, the sulfur content in the fuel oil is 50-200 ppm;

preferably, the weight percentage of the hydrogen peroxide solution is 30 wt%.

In one or more embodiments of the invention, the reaction temperature is 65-80 ℃, and the reaction time is 90-120 min.

In some more specific embodiments, the specific operation steps are as follows:

(1) mixing hydrochloric acid solution of tetraethyl orthosilicate (TEOS) with ethanol, adjusting pH value, hydrolyzing at constant temperature, heating and evaporating to form gel, drying the gel at constant temperature to obtain white or light yellow powder, and grinding to obtain the porous silicon dioxide.

(2) Dissolving imidazole salt in distilled water to obtain a solution A, and dissolving phosphotungstic acid in distilled water to obtain a solution B. And adding the porous silica suspension into the solution A, stirring, slowly dropwise adding the solution B to generate white precipitate, and filtering, washing and drying to obtain the novel catalytic oxidation desulfurization catalyst.

(3) Adding the catalyst into the vehicle fuel oil, and uniformly stirring to form a mixture.

(4) Adding acetic acid and oxidant H into the mixture₂O₂And the reaction is carried out.

(5) And (3) after the reaction is stopped, taking the upper oil phase, washing with water, extracting to obtain desulfurized ultra-low sulfur vehicle fuel oil, and measuring the sulfur content by using a microcoulometer. The catalyst is recovered by filtration or centrifugation, and can be reused after being washed and dried.

Preferably, the ratio of the mass of the catalytic oxidation desulfurization catalyst to the volume of the fuel oil is 0.001-0.002g:1mL, preferably 0.001-0.0015g:1 mL.

According to the invention, preferably, the concentration of the HCl solution in the step (1) is 0.2mol/L, the pH value of the mixed solution is 2-4, the constant-temperature hydrolysis temperature is 50-60 ℃, the hydrolysis time is 6-7h, the gel is dried at the constant temperature of 70-100 ℃ to obtain white or light yellow powder, and the white or light yellow powder is ground to obtain the porous silicon dioxide.

According to the invention, the imidazole salt in the step (2) is 1-butyl-3-methylimidazole bromide salt, 1-hexyl-3-methylimidazole chloride salt, 1-hexyl-3-methylimidazole bromide salt, 1-butyl-3-methylimidazole chloride salt or 1-butyl-3-methylimidazole carboxylate, the molar ratio of the imidazole salt to phosphotungstic acid is 3.05:1, and the loading mass fraction is 20-40%.

According to the invention, preferably, after the suspension is added in step (2), the mixture is stirred for 1 to 3 hours at a temperature of between 30 and 40 ℃.

According to the present invention, preferably, the drying conditions in the step (2) are: drying for 8-24h at 50-80 ℃.

According to the invention, the mixing ratio of the mass of the catalyst in the step (3) and the volume of the vehicle fuel oil is preferably 0.001-0.002g/mL, and more preferably 0.001-0.0015 g/mL.

According to the invention, the organic sulfide in the automotive fuel oil in the step (3) is a thiophene sulfide, preferably a dibenzothiophene sulfide; the sulfur content of the automotive fuel oil is 50-200 ppm.

According to the invention, preferably, H in the step (4)₂O₂The weight percentage of the aqueous solution was 30 wt%; h₂O₂The molar ratio of the sulfur to the sulfur in the automotive fuel oil is 3-7: 1, the reaction temperature is 65-80 ℃, and the reaction time is 90-120 min.

According to the invention, the extraction solvent used in the step (5) is one of water, methanol water solution, nitrogen-nitrogen dimethylformamide, nitrogen-nitrogen dimethylacetamide and dimethyl sulfoxide; the mixing volume ratio of the extracting agent to the vehicle fuel oil is 5: 1-1: 10.

In a second aspect of the invention, the ultra-low sulfur fuel oil is prepared by a method for catalyzing fuel oil by a catalytic oxidation desulfurization catalyst.

Preferably, the sulfur content in the ultra-low sulfur fuel oil is lower than 1.6 ppm;

preferably, the sulfur content of the ultra-low sulfur fuel oil is less than 0.4 ppm.

The third aspect of the invention provides an application of ultra-low sulfur fuel in the fields of vehicles and construction.

The present invention is described in further detail below with reference to specific examples, which are intended to be illustrative of the invention and not limiting.

Example 1

The embodiment adopts a mixed settling method to prepare the oxidative desulfurization catalyst, and comprises the following steps:

(1) preparation of catalyst carrier porous silica

Accurately weighing 10ml TEOS, 2ml 0.1mol/L HCl solution and 18ml ethanol, mixing, hydrolyzing at constant temperature of 60 deg.C for 6h, heating and evaporating to form gel, stirring at constant temperature of 80 deg.C for 16h to obtain light yellow powder, grinding into powder in a salt pot, and storing for use.

(2) Synthesis of 1-butyl-3-methylimidazolium bromide ([ BMIM ] Br)

8.34g of 1-bromobutane is added dropwise to 5g of 1-methylimidazole, the mixture is stirred for 24 hours at a constant temperature of 80 ℃, the product is washed by dry ethyl acetate, vacuum distilled and dried in a vacuum drying oven, and yellowish [ BMIM ] Br is obtained.

(3) Catalyst loading

Weighing 1g of the porous SiO prepared in step (1)₂Dissolved in 50ml of deionized water to form a suspension, and 0.0557g of [ BMIM ] prepared in step (2) was added]And (3) slowly dripping a Br aqueous solution into the suspension, fully stirring for 1.5h at 40 ℃, then slowly dripping 30ml of a phosphotungstic acid aqueous solution dissolved with 0.244g to generate a white precipitate, filtering, washing to obtain an oily solid on the surface, and drying at 60 ℃ to obtain the oxidative desulfurization catalyst, wherein the loading mass fraction of the imidazole phosphotungstate is 30%. The desulfurized catalyst is recovered by centrifugation or filtration and can be reused after being dried at 80 ℃.

(4) Dibenzothiophene was dissolved in isooctane to make a model oil with a sulfur content of 200 ppm.

(5) 50mL of a model oil was put in a 100mL three-necked flask, and 0.07g of a catalyst was added to the reaction system and stirred. According to 0.1mol/L acetic acid, 30 wt% H₂O₂And the molar ratio of S is 1:1:6, adding the mixture into a reaction system, and stirring the mixture for reaction for 100 minutes at the temperature of 75 ℃.

(6) And (4) after the reaction is finished, taking the upper oil phase, washing with water for three times, and measuring the sulfur content by using a micro coulometer.

Example 2

In the embodiment, a mixed settling method is adopted to prepare the oxidative desulfurization catalyst, commercially available silicon dioxide is used as a carrier, the specific loading and recovery mode is consistent with that of the step (3) in the embodiment 1, and the loading mass fraction of the imidazole phosphotungstate is 30%.

Steps (4) to (6) are the same as in example 1.

Examples 3 to 5

The butyl imidazole bromide in example 1 was replaced by [ HMIM ] Cl (example 3), [ BMIM ] Cl (example 4) and [ BMIM ] COOH (example 5), respectively, and the remaining steps were completely identical, with the imidazole phosphotungstates loading mass fractions all being 30%. Steps (4) to (6) are the same as in example 1.

Comparative example 1

The difference from example 1 is that the catalytic reaction was carried out without using acetic acid. The remaining parameters were the same as in example 1.

Comparative example 2

The difference from example 1 is that the molar ratio of acetic acid to hydrogen peroxide is 2: 1. the remaining parameters were the same as in example 1.

Comparative example 3

The difference from example 1 is that the molar ratio of acetic acid to hydrogen peroxide is 1: 2. the remaining parameters were the same as in example 1.

The results of the experiment are shown in table 1.

TABLE 1 desulfurization Effect under different experimental conditions

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.