JP2008280454A - Desulfurization agent for organosulfur compound-containing liquid state oil and method of desulfurization by using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a desulfurizing agent capable of removing an organosulfur compound contained in liquid state oil, especially a hardly decomposable organosulfur compound in a good efficiency, and a method of desulfurization by using the desulfurizing agent. <P>SOLUTION: This desulfurizing agent for the organosulfur compound-containing liquid state oil is characterized by containing a peroxyurea as a component (A), a carboxylic acid as a component (B) and an inorganic acid and/or organosulfonic acid as a component (C), and the method of desulfurization is characterized by treating the organosulfur compound-containing liquid state oil by using the desulfurizing agent. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a desulfurization agent for oxidative desulfurization of an organic sulfur compound contained in a liquid oil, and a desulfurization method using the same.

  Sulfur compounds contained in fuel oils made from fossil resources such as oil and coal produce sulfur oxides during combustion and cause air pollution. The main cause is sulfur oxides contained in the exhaust gas of automobiles that use diesel oil as fuel. The sulfur content of fuel oil in recent years has been regulated to 50 ppm or less, and further regulations will be strengthened in the future. Is expected. Therefore, desulfurization technology for sulfur compounds contained in fuel oil has been actively developed, and at present refineries, hydrodesulfurization methods that perform hydrotreating in the presence of a catalyst are being carried out. .

  By the way, in such fuel oils such as light oils, organic sulfur compounds that are extremely difficult to remove by hydrodesulfurization, particularly alkyl-substituted dibenzothiophenes having a sterically hindered substituent such as an alkyl group near the sulfur atom. In order to reduce the sulfur content to 50 ppm or less, it is necessary to effectively desulfurize these hardly decomposable organic sulfur compounds. Therefore, in order to achieve ultra-deep desulfurization, there is an urgent need to develop a new desulfurization technique that can effectively remove such persistent organic sulfur compounds.

  Various desulfurization methods have been devised. Conventionally, as a method of desulfurization, it is common to use a metal-based catalyst, and the method is usually performed at present. However, when only a metal-based catalyst is used, it is difficult to completely desulfurize the hardly decomposable organic sulfur compound as described above. In recent years, it has been considered to use an oxidizing agent in combination with a metal-based catalyst ( For example, see Patent Documents 1 and 2).

  However, although the method using such an oxidant is effective to some extent, the hard-to-decompose organic sulfur compound is difficult to be decomposed. When a solvent is used as in Patent Document 1, the processing time and cost for solvent treatment are increased. In order to increase the number, a more efficient desulfurization method has been demanded.

JP 2001-354978 A Japanese Patent Application Laid-Open No. 2002-322483

  Accordingly, the problem to be solved by the present invention is to provide a desulfurization agent that can efficiently remove organic sulfur compounds, particularly hardly decomposable organic sulfur compounds, contained in liquid oil, and a desulfurization method using the desulfurization agent. There is to do.

  Accordingly, the present inventors have intensively studied and found a desulfurizing agent that can efficiently remove a hardly-decomposable organic sulfur compound, and have reached the present invention. That is, a desulfurizing agent for liquid oil containing an organic sulfur compound comprising urea peroxide as component (A), carboxylic acid as component (B), and inorganic acid and / or organic sulfonic acid as component (C). is there.

  The effect of the present invention is to provide a desulfurizing agent capable of efficiently removing an organic sulfur compound contained in a liquid oil, particularly a hardly decomposable organic sulfur compound, and a desulfurization method using the desulfurizing agent.

Hereinafter, the present invention will be described in detail based on preferred embodiments thereof.
First, the component (A) will be described. The component (A) urea peroxide is produced using urea and hydrogen peroxide as raw materials. The production method thereof is, for example, 1 to 3 moles of hydrogen peroxide per mole of urea, preferably 1 Add 1 to 2 moles, mix at 30 to 80 ° C. for 1 to 10 hours, cool, precipitate urea peroxide crystals, separate and dry. If the amount of hydrogen peroxide is less than 1 mole, the reaction rate becomes slow, and a large amount of unreacted urea may remain. If the amount of hydrogen peroxide exceeds 3 moles, a large amount of unreacted hydrogen peroxide remains. May end up. In addition, hydrogen peroxide used as a raw material usually circulates in the form of an aqueous solution. However, if a low concentration of hydrogen peroxide is used, a large amount of water enters the reaction system, and urea peroxide is precipitated. Since it becomes difficult, it is preferable to use a hydrogen peroxide solution having a high concentration of 50% by mass or more.

  Next, the carboxylic acid of component (B) is not particularly limited as long as it is a compound having a carbonyl group. For example, formic acid, acetic acid, propionic acid, butanoic acid (butyric acid), pentanoic acid (valeric acid), isopentanoic acid (Isovaleric acid), hexanoic acid (caproic acid), heptanoic acid, isoheptanoic acid, octanoic acid (caprylic acid), 2-ethylhexanoic acid, isooctanoic acid, nonanoic acid (pelargonic acid), isononanoic acid, decanoic acid (capric acid) ), Isodecanoic acid, undecanoic acid, isoundecanoic acid, dodecanoic acid (lauric acid), isododecanoic acid, tridecanoic acid, isotridecanoic acid, tetradecanoic acid (myristic acid), hexadecanoic acid (palmitic acid), octadecanoic acid (stearic acid), isostearic acid Aliphatic carboxylic acids such as acids; benzoic acid, phthalic acid, isophthalic acid, terephthalic , Hemimellitic acid, trimellitic acid, pyromellitic acid, toluic acid, aromatic carboxylic acids such as salicylic acid; monofluoroacetic acid, difluoro acetic acid, trifluoroacetic acid, such as trifluoroacetic acid. Among these carboxylic acids, formic acid, acetic acid, propionic acid, and fluoroacetic acid, which are low molecular weight carboxylic acids, are preferable because purification after treatment is easy and the addition amount is small. Formic acid, acetic acid, Trifluoroacetic acid is more preferred.

  (C) The inorganic acid and organic sulfonic acid of a component are demonstrated. First, examples of the inorganic acid include hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, polyphosphoric acid, phosphorous acid, hydrocyanic acid, odorous acid, iodine acid, nitrous acid, carbonic acid, and boric acid. Of these, sulfuric acid, nitric acid, and phosphoric acid are preferably used because they are easy to handle and inexpensive. Examples of the organic sulfonic acid include naphthalene-α-sulfonic acid, naphthalene-β-sulfonic acid, paratoluenesulfonic acid, methanesulfonic acid, benzenesulfonic acid, and isethionic acid. Among these, it is preferable to use methanesulfonic acid or isethionic acid having a relatively small molecular weight, which is small in addition amount and easy to purify at the end of the reaction. The above inorganic acid and organic sulfonic acid may be used alone or in combination, but it is preferable to use an inorganic acid because it is easy to handle and highly effective.

  The above components (A) to (C) may be blended and used at an arbitrary ratio, but in order to further enhance the effect of desulfurization, (B) components 10 to 1500 are used with respect to 100 parts by mass of component (A). A mass part is preferable and 50-500 mass parts is more preferable. Moreover, 1-300 mass parts is preferable with respect to 100 mass parts of (A) component, and (C) component is more preferable 5-50 mass parts.

  There is no restriction | limiting in particular in the liquid oil used for this invention, It can utilize for general fuel oil, lubricating oil, etc. containing a sulfur compound. Examples of such fuel oil and lubricating oil include gasoline, light oil, heavy oil, kerosene, jet fuel, liquefied natural gas, alcohol, LPG, naphtha, asphalt oil, oil sand oil, coal liquefied oil, shell oil, waste plastic oil, Biofuel, GTL, paraffinic mineral oil, naphthenic mineral oil, or refined mineral oil obtained by refining these can be used. Among these, fuel oils in which sulfur oxides during combustion are a problem are preferable, and gasoline, light oil, and kerosene are more preferable.

  These liquid oils mainly contain organic sulfur compounds derived from raw materials. Examples of such organic sulfur compounds include thiols, thioethers, thiophenols, thioanisoles, thiophenes, benzothiophenes, And dibenzothiophenes. Among these organic sulfur compounds, heterocyclic compounds containing a sulfur atom in the skeleton, especially dibenzothiophenes having a substituent such as an alkyl group around the sulfur atom, are decomposed by the effects of steric hindrance in ordinary hydrodesulfurization methods. In the present invention, even such a hardly decomposable organic sulfur compound can be easily oxidized and removed.

  The desulfurization method of the present invention is a method in which the desulfurization agent of the present invention and liquid oil are brought into contact with each other. Examples of the contact method include a method in which the desulfurization agent of the present invention is filled in an adsorption tower and the liquid oil is circulated. A method in which liquid oil is placed in a container such as a tank in which the desulfurizing agent of the present invention is fixed and left standing or stirring, and the liquid oil and the desulfurizing agent of the present invention are placed in a container such as a tank to remove the desulfurizing agent after the reaction. Methods and the like. The reaction temperature at the time of desulfurization is preferably -40 to 100 ° C, and more preferably -20 to 80 ° C. When the reaction temperature is lower than −40 ° C., the fluidity of the fuel oil is lowered, and the reaction may not proceed smoothly. When the reaction temperature is higher than 100 ° C., the decomposition reaction of urea peroxide may proceed preferentially. Absent. The pressure during the reaction is preferably in the range of normal pressure to 1 MPa. Moreover, 1-20 hours are preferable and, as for the time which makes the desulfurization agent of this invention and liquid oil contact, 3-15 hours are more preferable. If it is shorter than 1 hour, the oxidation reaction of the organic sulfur compound may not be completed completely, and contact exceeding 20 hours is not preferable because the reaction rate is hardly changed and economical loss may be increased.

  As the oxidation reaction of the organic sulfur compound proceeds, hydrogen peroxide contained in urea peroxide, which is the component (A) of the desulfurization agent of the present invention, decreases. If hydrogen peroxide is completely eliminated, the performance of the component (A) as an oxidant is lost, so the amount of liquid oil that can be refined is limited. Therefore, although depending on the amount of the organic sulfur compound in the liquid oil, the liquid oil is usually preferably 2000 parts by mass or less and more preferably 1000 parts by mass or less with respect to 1 part by mass of the desulfurization agent of the present invention.

  In order to treat the organic sulfur oxide generated by the oxidation reaction, the component (B), and the component (C), they may be removed using various separation operations such as extraction, adsorption, and distillation. Examples of the adsorbent for the adsorption operation include silica polar particles, zeolites, molecular sieves, activated clay, ion exchange resins, adsorbent resins, viscous minerals, activated carbon, and the like, which have molecular polar adsorption or molecular sieving action. In addition to the above treatment operation, the organic sulfur oxide can be completely removed by purification by distillation. Since the component (A) remains as a solid, it can be easily removed by filtration, distillation, or the like.

Hereinafter, the present invention will be specifically described by way of examples. In the following examples and the like,% and ppm are based on mass unless otherwise specified. In addition, the effective hydrogen peroxide in an Example and a comparative example is the ratio of the hydrogen peroxide which occupies for urea peroxide.
<Analysis method>
As the model sulfur compound, hardly decomposed 4,6-dimethyldibenzothiophene was used, and the decomposition rate of 4,6-dimethyldibenzothiophene was confirmed by high performance liquid chromatography (HPLC). The sulfur concentration in the liquid was confirmed by the sulfur content using a high frequency inductively coupled plasma (ICP) emission spectrometer. The results are shown in Table 1. The details of both analytical instruments are as follows.
(HPLC analysis method)
Column: ODS column (LUNA 5C18 RS, φ4.6mm × 250mm)
Eluent: acetonitrile / water = 75/25
Flow rate: 1.0 mL / min
Detector: UV, 325nm
Column oven temperature: 40 ° C
(Analysis method of ICP (Inductively Coupled Plasma) emission analysis)
Analytical instrument: ICPS-8100 manufactured by Shimadzu Corporation
Analysis method: Internal standard correction method (diluted solvent xylene)

<Example 1>
Model light oil (4,6-dimethyldibenzothiophene-containing octane: total sulfur component 50 ppm) to 500 ml of urea peroxide (effective hydrogen peroxide: 36.1%) 0.185 g, trifluoroacetic acid 0.35 g and sulfuric acid (89% by mass) After adding 0.08 g and stirring at 40 ° C. for 4 hours, the concentration of 4,6-dimethyldibenzothiophene remaining was examined by HPLC analysis. Thereafter, the obtained model light oil was purified by distillation, and the total sulfur concentration in the liquid was examined using ICP.

<Example 2>
Model light oil (4,6-dimethyldibenzothiophene-containing octane: total sulfur component 50 ppm) to 500 ml of urea peroxide (effective hydrogen peroxide: 36.1%) 0.185 g, formic acid 0.6 g and sulfuric acid (89 mass%) 0 After adding 0.08 g and stirring at 40 ° C. for 7 hours, the concentration of 4,6-dimethyldibenzothiophene remaining was examined by HPLC analysis. Thereafter, the obtained model light oil was purified by distillation, and the total sulfur concentration in the liquid was examined using ICP.

<Example 3>
To 500 ml of commercially available light oil (total sulfur component: 350 ppm), 1.34 g of urea peroxide (effective hydrogen peroxide: 36.1%), 0.6 g of formic acid and 0.08 g of sulfuric acid (89% by mass) were added, and the mixture was heated at 40 ° C. Stir for hours. Thereafter, 10 g of silica gel was added to the obtained light oil and stirred at 27 ° C. for 1 hour. The silica gel was removed by filtration and purified by distillation. The total sulfur concentration in the liquid was examined using ICP.

<Example 4>
Model light oil (4,6-dimethyldibenzothiophene-containing octane: total sulfur component 50 ppm) to 500 ml of urea peroxide (effective hydrogen peroxide: 36.1%) 0.185 g, trifluoroacetic acid 0.35 g and isethionic acid 0.01 g After stirring at 40 ° C. for 4 hours, the concentration of 4,6-dimethyldibenzothiophene remaining was examined by HPLC analysis. Thereafter, the obtained model light oil was purified by distillation, and the total sulfur concentration in the liquid was examined using ICP.

<Comparative Example 1>
1.11 g of a large excess of urea peroxide (effective hydrogen peroxide: 36.1%) was added to 500 ml of model light oil (4,6-dimethyldibenzothiophene-containing octane: total sulfur component 50 ppm), and the mixture was stirred at 40 ° C. for 10 hours. Thereafter, the concentration of 4,6-dimethyldibenzothiophene remaining was examined by HPLC analysis.

<Comparative example 2>
0.185 g of urea peroxide (effective hydrogen peroxide: 36.1%) and 0.6 g of formic acid were added to 500 ml of model light oil (4,6-dimethyldibenzothiophene-containing octane: total sulfur component 50 ppm) and stirred at 40 ° C. for 7 hours. After that, the concentration of 4,6-dimethyldibenzothiophene remaining was examined by HPLC analysis. Thereafter, the obtained model light oil was purified by distillation, and the total sulfur concentration in the liquid was examined using ICP.

<Comparative Example 3>
After adding 0.19 g of 35.6% hydrogen peroxide water and 0.35 g of trifluoroacetic acid to 500 ml of model light oil (4,6-dimethyldibenzothiophene-containing octane: total sulfur component 50 ppm), the mixture was stirred at 40 ° C. for 4 hours, The residual 4,6-dimethyldibenzothiophene concentration was determined by HPLC analysis. Thereafter, the obtained model light oil was purified by distillation, and the total sulfur concentration in the liquid was examined using ICP.

<Comparative Example 4>
Model light oil (4,6-dimethyldibenzothiophene-containing octane: total sulfur component 50 ppm) to 500 ml of potassium persulfate (1.11 equivalent to sulfur atom) 0.4 g, 0.35 g of trifluoroacetic acid and sulfuric acid (89% by mass) After adding 0.08 g and stirring at 40 ° C. for 4 hours, the concentration of 4,6-dimethyldibenzothiophene remaining was examined by HPLC analysis. Thereafter, the obtained model light oil was purified by distillation, and the total sulfur concentration in the liquid was examined using ICP.

  From the above results, it can be seen that when the desulfurization agent and the desulfurization method of the present invention are used, the organic sulfur compound, particularly the hardly decomposable organic sulfur compound, contained in the liquid oil can be efficiently removed.

Claims (6)

  An organic sulfur compound-containing liquid oil desulfurization agent comprising urea peroxide as component (A), carboxylic acid as component (B), and inorganic acid and / or organic sulfonic acid as component (C).   The desulfurizing agent according to claim 1, wherein the component (B) is at least one selected from formic acid, acetic acid, and trifluoroacetic acid.   The desulfurizing agent according to claim 1 or 2, wherein the component (C) is at least one selected from methanesulfonic acid, isethionic acid, phosphoric acid, nitric acid, and sulfuric acid.   The component (A) contains 10 to 1500 parts by mass of the component (B) and 1 to 300 parts by mass of the component (C) with respect to 100 parts by mass of the component (A). The desulfurization agent according to one item.   An organic sulfur compound-containing liquid oil is treated with the desulfurizing agent according to any one of claims 1 to 4.   The organic sulfur compound-containing liquid oil is gasoline, light oil, heavy oil, kerosene, jet fuel, liquefied natural gas, alcohol, LPG, naphtha, asphalt oil, oil sand oil, coal liquefied oil, shell oil, waste plastic oil, biofuel The desulfurization method according to claim 5, wherein the desulfurization method is at least one selected from GTL, paraffinic mineral oil, and naphthenic mineral oil.