JP2008169356A - Method for producing liquid fuel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a liquid fuel by which the yield of an intermediate fraction can selectively be improved while maintaining the cracking activity of a catalyst at a sufficient high level when a raw material oil containing a paraffinic hydrocarbon is subjected to a hydrocracking treatment. <P>SOLUTION: The method for producing the liquid fuel is carried out as follows: The catalyst comprising a carrier containing a crystalline aluminosilicate and an amorphous solid acid and platinum supported on the carrier with a platinum compound without containing chlorine as a constituent element is brought into contact with the raw material oil containing the paraffinic hydrocarbon to carry out the hydrocracking treatment. Thereby, a cracking product oil is obtained. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing liquid fuel from paraffinic hydrocarbons by hydrocracking.

  In recent years, there has been a rapid increase in demand for clean liquid fuels that are low in sulfur and aromatic hydrocarbons and are environmentally friendly. In response to this, various clean fuel manufacturing methods have already been studied in the fuel oil manufacturing industry. Among these, expectations are high for a process for hydrocracking paraffinic hydrocarbons such as wax in the presence of a catalyst.

The hydrocracking process using vacuum gas oil as a raw material is an established technology having a history of several decades and has already been commercialized. However, in such a hydrocracking process, if paraffinic hydrocarbons are used as a raw material instead of vacuum gas oil, the hydrocracking reactivity of paraffinic hydrocarbons is significantly different from that of vacuum gas oil. It is difficult to divert the catalyst as it is. For this reason, research and development has been vigorously conducted for the purpose of developing high performance catalysts for paraffinic hydrocarbons. For example, a catalyst in which platinum is supported on a support containing silica alumina has been proposed. (For example, refer to Patent Document 1).
JP-A-6-41549

  However, the conventional hydrorefining process using the catalyst has room for improvement in the following points. That is, in the hydrocracking process of paraffinic hydrocarbons, from the viewpoint of economy, (1) the cracking activity of the catalyst is high, and (2) the yield of middle distillate is high. It is important in raising. However, if the cracking activity of the catalyst is high, the middle distillate once produced is easily decomposed, so that the yield of the middle distillate is reduced, and as a result, the economics of the process is lowered. In other words, since (1) and (2) are in a trade-off relationship, it is very difficult to achieve both (1) and (2). This is the hydrocracking of paraffinic hydrocarbons. This is a major obstacle to improving the economics of the process.

  The present invention has been made in view of such circumstances, and yields a middle distillate while maintaining cracking activity of a catalyst sufficiently high when hydrocracking a feedstock containing paraffinic hydrocarbons. An object of the present invention is to provide a method for producing a liquid fuel capable of selectively improving the above.

  In order to solve the above-described problems, the present invention provides a carrier containing crystalline aluminosilicate and an amorphous solid acid, a platinum-containing catalyst supported on a carrier using a platinum compound not containing chlorine as a constituent element, and a paraffin-based catalyst. There is provided a method for producing a liquid fuel, characterized in that a cracked oil is obtained by performing hydrocracking treatment with a feedstock oil containing hydrocarbons.

  The “middle fraction” in the present invention means a fraction having a boiling range of 145 to 360 ° C. The “hydrocracking” in the present invention may include an isomerization reaction from normal paraffin to isoparaffin in addition to the paraffin hydrocarbon decomposition reaction.

  Moreover, in this invention, it is preferable that the said raw material oil contains 70 mass% or more normal paraffin. By hydrocracking such feedstock, it is possible to selectively increase the yield of middle distillate while maintaining the cracking activity of the catalyst sufficiently high.

  In the present invention, the crystalline aluminosilicate is preferably ultra-stabilized Y-type zeolite. This makes it possible to selectively increase the yield of middle distillate.

  In the present invention, the amount of platinum supported on the carrier is preferably 0.1 to 2.0% by mass relative to the mass of the carrier. This makes it possible to selectively increase the yield of the middle distillate while maintaining the cracking activity of the catalyst sufficiently high.

  Moreover, in this invention, it is preferable that raw material oil contains the paraffinic hydrocarbon produced | generated by the reduction reaction of carbon monoxide. Thereby, normal paraffin can be efficiently converted to isoparaffin while maintaining the cracking activity of the catalyst and the middle distillate yield at a high level.

  In the present invention, the ratio of the paraffinic hydrocarbon having a boiling point of less than 360 ° C. in the cracked product oil to the paraffinic hydrocarbon having a boiling point of 360 ° C. or higher in the raw material oil is preferably 70% by mass or more.

  In the present invention, the platinum compound is preferably one or more compounds selected from tetraammineplatinum (II) nitrate and dinitrodiammineplatinum (II).

  According to the present invention, when liquid fuel is produced from feedstock containing paraffinic hydrocarbons by hydrocracking, the yield of middle distillate is selectively improved while maintaining the cracking activity of the catalyst sufficiently high. The manufacturing method of the liquid fuel which can be provided can be provided.

  Preferred embodiments of the present invention are described in detail below.

  In the present invention, a support containing a crystalline aluminosilicate and an amorphous solid acid and a catalyst containing platinum supported by using a platinum compound not containing chlorine as a constituent element are used. Crystalline aluminosilicate means a crystalline metal oxide composed of three elements of aluminum, silicon, and oxygen. In addition, although other metal elements may coexist within a range not hindering the effects of the present invention, the ratio of the other metal elements to the total mass of alumina and silica may be 5% by mass or less in terms of oxide. Preferably, it is 3 mass% or less. Examples of the coexisting metal element include titanium, lanthanum, manganese, gallium, and zinc. Among these, titanium and lanthanum are preferable from the viewpoint of increasing the yield of middle distillate.

The crystallinity of aluminosilicate can be estimated by the ratio of tetracoordinate aluminum atoms in all aluminum atoms, and this ratio can be measured by ²⁷ Al solid state NMR. The crystalline aluminosilicate of the present invention means an aluminosilicate in which the ratio of tetracoordinated aluminum atoms to all aluminum atoms is 70% or more. That is, if this ratio is 70% or more, any of them can be used as the crystalline aluminosilicate of the present invention. Although there is no particular limitation, those having a ratio of 80% or more, preferably 85% or more can be used.

  As the crystalline aluminosilicate, so-called zeolite can be used. As the crystalline aluminosilicate, Y-type or ultra-stabilized Y-type (USY-type) zeolite, beta-type zeolite, and mordenite can be preferably used, and more preferably ultra-stabilized Y-type (USY-type) zeolite is used. it can. Further, if necessary, two or more crystalline aluminosilicates can be used in combination.

  The average particle size of the crystalline aluminosilicate is not particularly limited, but is preferably 1.0 μm or less, particularly preferably 0.5 μm or less. The smaller the particle size of the crystalline aluminosilicate, the more preferable the yield of middle distillate in the cracked product oil tends to increase.

  Although there is no restriction | limiting in particular in content of crystalline aluminosilicate, Usually, it can use in the range of 0.1-20 mass% on the basis of the total mass of a support | carrier.

  Examples of the amorphous solid acid contained in the carrier include silica alumina, silica zirconia, silica titania, silica magnesia, alumina zirconia, and alumina boria. Among these, silica alumina and alumina boria are preferable from the viewpoint of achieving both high catalytic cracking activity and middle distillate yield.

  Although there is no restriction | limiting in particular in the quantity of an amorphous solid acid, Usually, it can use in the range of 5-70 mass% on the basis of the total mass of a support | carrier.

  The carrier containing the crystalline aluminosilicate and the amorphous solid acid can be molded without using a binder, but the crystalline aluminosilicate and the amorphous solid acid can be molded using a binder. The molded body can be used as a carrier. The binder to be used is not particularly limited, but alumina, silica and the like can be used, and among these, alumina is preferable. Although there is no restriction | limiting in particular in the ratio of the binder used for shaping | molding, Preferably it is 20-90 mass% on the basis of the total mass of a support | carrier, More preferably, it is 40-80 mass%. When the ratio of the binder is less than 20% by mass, the strength of the carrier tends to be weak, and when it exceeds 90% by mass, the effect of the present invention tends to be insufficient.

  The catalyst is obtained by supporting platinum on a carrier containing the above crystalline aluminosilicate and an amorphous solid acid.

  The selection of a platinum compound for supporting platinum on a carrier is particularly important. In the present invention, a platinum compound containing no chlorine is used as a constituent element. The platinum compound is not particularly limited as long as it does not contain chlorine as a constituent element, and specifically, tetraammineplatinum (II) nitrate and dinitrodiammineplatinum (II) are preferable.

  In addition, it is preferable that the said platinum compound does not contain chlorine as an impurity as much as possible. Thereby, a catalyst having a sufficiently reduced chlorine concentration can be prepared.

  There is no particular limitation on the method for supporting platinum, and an impregnation method, an incipient wetness method, and an ion exchange method can be generally used. The amount of platinum supported on the carrier is preferably 0.1 to 2.0% by mass, more preferably 0.4 to 1.2% by mass with respect to the mass of the carrier. If the supported amount of platinum is less than 0.1% by mass, the yield of middle distillate tends to decrease, and if the supported amount of platinum exceeds 2.0% by mass, the decomposition activity of the catalyst tends to decrease.

  In addition to the above platinum, palladium can also be used by being supported on a carrier. There is no restriction | limiting in particular in the loading method of palladium, For example, it can carry | support on a support | carrier simultaneously with platinum. When palladium is also supported, it is important to use a palladium compound that does not contain chlorine as a constituent element. Specifically, palladium nitrate, palladium acetate, tetraammine palladium (II) nitrate, dinitrodiammine palladium (II), and the like can be used.

  When the catalyst contains both platinum and palladium, the ratio of palladium to platinum (palladium / platinum, molar ratio) is preferably 1.5 or less, and more preferably 0.2 to 0.8. If the ratio exceeds 1.5, the yield of middle distillate tends to decrease.

  Petroleum and synthetic hydrocarbon oils can be used as the feedstock oil, but paraffin hydrocarbons are preferred. As used herein, the paraffinic hydrocarbon means a hydrocarbon oil containing 70% by mass or more of normal paraffin. As the raw material oil, a paraffinic hydrocarbon which is solid at normal temperature having 18 or more carbon atoms in one molecule, that is, a paraffinic hydrocarbon usually referred to as wax can be used more preferably.

  Although there is no restriction | limiting in particular about the manufacturing method of the paraffinic hydrocarbon contained in raw material oil, The FT wax produced | generated by the Fischer-Tropsch synthesis which is a reduction reaction of carbon monoxide is preferable.

  In the hydrocracking, a conventional fixed bed reactor can be used. The reaction conditions of the raw material oil and the catalyst in the fixed bed reactor are preferably a temperature of 200 to 450 ° C., a hydrogen pressure of 0.5 to 15 MPa, and a liquid space velocity of the raw material oil of 0.1 to 10 / h. It is more preferable to set it to -370 degreeC, hydrogen pressure 2.0-8.0MPa, and liquid space velocity 0.3-5.0 / h of raw material oil.

  The cracked product oil obtained by hydrocracking treatment is a fraction having a boiling point of less than 145 ° C. (LPG, naphtha fraction, etc.) in addition to the middle fraction (the fraction having a boiling range of 145 to 360 ° C.) as the main component. And a fraction having a boiling point exceeding 360 ° C. The middle fraction can be separated into a kerosene fraction (a fraction having a boiling range of 145 to 260 ° C.) and a light oil fraction (a fraction having a boiling point range of 260 to 360 ° C.) by distillation or the like.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example at all.

(Preparation of catalyst A)
30 g of ultra-stabilized Y type (USY type) zeolite (silica / alumina (molar ratio): 31) with an average particle size of 0.6 μm, 500 g of silica alumina (alumina content: 14 mass%), and 400 g of boehmite are mixed. A cylindrical molded body having a diameter of 1/16 inch (about 1.6 mm) was obtained using the mixture. This cylindrical molded body was fired in air at 500 ° C. for 1 hour to obtain a carrier. This support was impregnated with an aqueous solution of tetraammineplatinum (II) nitrate so that the platinum was 0.8% by mass based on the mass of the support by the incipient wetness method. After impregnation, the catalyst A was obtained by drying at 120 ° C. for 3 hours and calcining at 500 ° C. for 1 hour.

(Preparation of catalyst B)
Catalyst B was obtained in the same manner as in the preparation of Catalyst A, except that alumina boria (boria content 15% by mass) was used instead of silica alumina (alumina content: 14% by mass).

(Preparation of catalyst C)
Tetraammineplatinum (II) nitrate is added to the support obtained in the same manner as in the preparation of catalyst A so that platinum is 0.6% by mass and palladium is 0.2% by mass based on the mass of the support by the incipient wetness method. And an aqueous solution containing palladium nitrate (palladium / platinum (molar ratio) = 0.61). After impregnation, the catalyst C was dried at 120 ° C. for 3 hours and calcined at 500 ° C. for 1 hour.

(Preparation of catalyst D)
Catalyst D was obtained in the same manner as Catalyst A except that chloroplatinic acid was used instead of tetraammineplatinum (II) nitrate.

(Preparation of catalyst E)
Catalyst E was obtained in the same manner as Catalyst B, except that chloroplatinic acid was used instead of tetraammineplatinum (II) nitrate.

(Example 1)
FT wax (normal paraffin content: 95% by mass, carbon number distribution: 21 to 60, boiling point of 360 ° C. or higher) is fed to a fixed bed flow reactor filled with catalyst A (100 ml). Hydrocracking treatment was carried out by supplying a content of 100% by mass). The hydrogen pressure during the hydrocracking treatment was 3 MPa, and the liquid space velocity of the raw material oil was 2.0 / h. By this hydrocracking treatment, a reaction temperature (80% by mass decomposition temperature) at which a decomposition product (a fraction having a boiling point of 360 ° C. or less) of 80% by mass with respect to the raw material oil is obtained, and an intermediate distillation with respect to the raw material oil at the reaction temperature The yield of the fraction (boiling point range: 145 to 360 ° C.) was determined. The obtained results are shown in Table 1.

(Example 2)
A hydrocracking treatment was performed in the same manner as in Example 1 except that the catalyst B was used instead of the catalyst A, and the 80 mass% cracking temperature and the yield of middle distillate were determined. The obtained results are shown in Table 1.

(Example 3)
A hydrocracking treatment was performed in the same manner as in Example 1 except that the catalyst C was used instead of the catalyst A, and the 80 mass% cracking temperature and the yield of middle distillate were determined. The obtained results are shown in Table 1.

(Comparative Example 1)
A hydrocracking treatment was performed in the same manner as in Example 1 except that the catalyst D was used instead of the catalyst A, and the 80 mass% cracking temperature and the yield of middle distillate were determined. The obtained results are shown in Table 1.

(Comparative Example 2)
A hydrocracking treatment was performed in the same manner as in Example 1 except that the catalyst E was used instead of the catalyst A, and the 80 mass% cracking temperature and the yield of middle distillate were determined. The obtained results are shown in Table 1.

  As shown in Table 1, it can be seen that in Examples 1 to 3, the 80% by mass decomposition temperature is lower than that of Comparative Examples 1 and 2, and the yield of middle distillate is high.

Claims (7)

A support containing crystalline aluminosilicate and an amorphous solid acid, and a catalyst containing platinum supported on the support using a platinum compound containing no chlorine as a constituent element;
A feedstock containing paraffinic hydrocarbons;
A method for producing a liquid fuel, wherein hydrocracking treatment is performed by bringing the cracked oil into contact with each other to obtain cracked product oil.   The method for producing a liquid fuel according to claim 1, wherein the raw material oil contains 70% by mass or more of normal paraffin.   The method for producing a liquid fuel according to claim 1 or 2, wherein the crystalline aluminosilicate is ultra-stabilized Y-type zeolite.   The amount of the platinum supported on the carrier is 0.1 to 2.0 mass% with respect to the mass of the carrier, according to any one of claims 1 to 3. Method for producing liquid fuel.   The method for producing a liquid fuel according to any one of claims 1 to 4, wherein the raw material oil includes paraffinic hydrocarbons produced by a reduction reaction of carbon monoxide.   The ratio of the paraffinic hydrocarbon having a boiling point of less than 360 ° C in the cracked product oil to the paraffinic hydrocarbon having a boiling point of 360 ° C or higher in the raw material oil is 70% by mass or more. The manufacturing method of the liquid fuel of any one of -5.   The liquid fuel according to any one of claims 1 to 6, wherein the platinum compound is at least one compound selected from tetraammineplatinum (II) nitrate and dinitrodiammineplatinum (II). Production method.