A method of processing low-octane gasoline fractions

 

(57) Abstract:

Usage: petrochemistry. The inventive low-octane gasoline fraction is subjected to reforming in the presence of a mixture of two catalysts, zeolite aluminosilicate catalyst C-10 and aluminoborosilicate oxide catalyst, preferably taken in the amount of 20 and 80 vol.% respectively. You can use this mixture, a modified lomographische, preferably in quantities of 1.0 to 1.5 wt.% when 753-743 K. Technical result is an increase in the yield of the target product. 3 C.p. f-crystals, 2 tab. , 2 Il.

The invention relates to a method of processing low-octane gasoline fractions by catalytic reforming unit for producing high-octane gasoline.

Known methods of processing low-octane gasoline fractions by catalytic reforming and high octane gasoline using various catalysts, such as zeolite (see U.S. Pat. EN N 2052286, 1996, U.S. Pat. US N 5755956, 1998, C-ku WO N 91/06616, 1991), including zeolite modified with methylphenylsiloxane (see U.S. Pat. EN N 2045569, 1995, U.S. Pat. EN N 1801983, 1993), aluminoborosilicate catalyst modified metalfinish the processing of gasoline fractions of different origin by atmospheric catalytic reforming (see ER N 0131975, 1985).

In this way the gasoline elevated in the presence of a mixture of two catalysts. One of the catalysts is a composition containing zinc, chromium and/or aluminum. It is derived from one or more precipitated residue formed by adding the main reactive agent to one or more aqueous solutions of salts of metals. Another catalyst is a crystalline silicate of the metal, which, after annealing for 1 hour in a stream of air at 500oC is characterized by the following indicators:

a) diffraction bands on the x-ray powder has 4 of the most powerful lines: 11,1 0,2; 10,0 0,2; 3,84 0,07; 3,72 0,06;

b) in a formula that reflects the composition of the silicate, in addition to the SiO2included Al2O3or Fe2ABOUT3or both of these compounds; the molar ratio of oxides SiO2/(Fe2ABOUT3+ Al2O3) > 10.

It is most preferable as a raw material in this way to use gasoline or its fractions obtained from catalytic cracking and reforming.

The disadvantage of this method is the relatively low yield of the final product.

The objective of this izopet increase the yield of the final product at a sufficiently high octane number.

To solve the problem in the proposed method of processing low-octane gasoline fractions by atmospheric catalytic reforming in the presence of a mixture of two catalysts, at elevated temperature, according to the invention, a mixture of aluminosilicate zeolite catalyst C-10 and aluminoborosilicate oxide catalyst.

While it is preferable to use a mixture of catalization containing about 30. % aluminosilicate zeolite catalyst C-10 and 70 vol.% alumnirelations oxide catalyst.

Preferably the process is carried out at a temperature of 753-773 K, at the space velocity of the raw material 0,3-0,6 h-1.

In addition, preferably in the described way to use a mixture of catalysts modified by lomographische, preferably in quantities of 1.0 to 1.5 wt.% from the mixture.

In the present invention using aluminosilicate zeolite catalyst C-10 (TU 38.1011372-94) and allocability oxide catalyst (TU 38.101194-96).

The invention is illustrated in the following examples, without limiting its scope.

In Fig.1 shows the effect of concentration is concentratie of lomographische to the exit of the catalyst to example 3.

Example 1. As catalysts for the reforming of low-octane gasoline fraction was applied to the individual catalysts and the mixture aluminosilicate zeolite catalyst C-10 and alumnirelations oxide catalyst. Zeolite aluminosilicate catalyst with rare earth elements has increased activity in the reactions of cracking and isomerization of hydrocarbons. Selecting a mixture of these catalysts, it is possible to regulate their selectivity and change the value of the octane number of the catalyst.

Used catalyst C-10 production Salavat catalyst factory had the following physico-mechanical properties:

- bulk density - 620 kg/m3,

- specific surface area of 420 m2/g

stable activity at the exit of the catalyst - to 53.8 wt.%

the selectivity for the exit of the catalyst - 81,8 wt.%

the REE content of 1.8 wt.%

- Na2O - 0.26 wt.%

- Fe2O3is 0.075 wt.%

content-zeolite - 10 wt.%

- the ratio of SiO2/Al2ABOUT3= 5,7.

Used aluminumalloy oxide catalyst had the following properties:

- the content in the catalyst in RA is sodium [Na2O] - 0,09

iron oxide [Fe2ABOUT3] - 0,05

sulfate [SO4]2- 1,5

- bulk density of 680 kg/m3,

- specific surface 180-220 m2/g

- pore volume - 0,50 cm3/g

the pressure in the fracture tablets - 1.8 kg/mm,

- the color of the catalyst - green.

As raw material for reforming used hydrotreated gasoline fraction, wikipaedia in the temperature range 85-185oC, with density - 747,9 kg/m3, a refractive index of nD20=1,4182 and octane number by the motor method - 61.5 points.

At the individual catalysts and their mechanical mixtures conducted experiments on the reforming of gasoline fractions at atmospheric pressure, the installation of flow type, in which downloaded 40 cm3catalyst (or mixture of catalysts). Experiments were performed at T=758 K, flow rate of feed of 0.6 h-1and duration of experience 1 hour. For catalyzate determined, the refractive index, density, octane number. To experience determined the gas outlet, catalysis and coke. Experimental data are shown in table 1, which revealed the influence of the composition of a mechanical mixture of catalysts C-10 and alumnirelations oxide on the shares is a mixture, containing 30 vol.% C-10 and 70 vol.% alumnirelations oxide catalyst. This mixture of the catalyst obtained gasoline with an octane number by the motor method 80,8 point and the resultant catalysate of 66.7 wt.%. The mixture of catalyst 50 and 50 vol.% accordingly allows to obtain gasoline with an octane rating of 82.5 points, but this reduces the output of high-octane gasoline to 60.5 wt.%.

Example 2. Optimal process conditions atmospheric catalytic reforming of gasoline fractions was determined by examining the kinetics of the process in a wide range of temperatures and volumetric flow rates of the raw material into the reactor for catalytic mixture containing 30 vol.% C-10 and 70 vol.% alumnirelations oxide catalyst. The experiment was carried out for one hour. For catalyzate determined yield, refractive index, density and octane number by the motor method. The results of the experiments are presented in table 2, which shows the optimization of reforming low-octane gasoline fraction at the catalyst mixture of 30 vol.% C-10 and 70 vol.% alumnirelations oxide catalyst.

From table 2 it follows that the commodity component of gasoline can be obtained at a flow rate of 0.3 h-1when T=753-773 K and at T=773 K for all volumetric flow rates gasoline fraction receive high-octane component of gasoline.

It is possible to obtain gasoline with an octane rating to 91.7 points by the motor method, i.e., up to 107 units on the research method.

Example 3. Modified mixture of catalysts C-10 and alumnirelations oxide optimal composition of 30% vol. C-10 and 70 vol.% alumnirelations oxide catalyst was carried lomographische. Alimohammadian synthesized by the reaction of the double exchange using dihydroxyphenylethanol sodium, aluminum chloride and chromium chloride. Was the compound obtained of General formula

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Alimohammadian was applied on the surface of the mixture of catalyst from the benzene solution was passed through the catalyst bed at a temperature of 70oC for 0.5-1 hour. The amount of benzene solution was 0.5 per volume of catalyst. This amount was sufficient for complete wetting of the catalyst solution, but not washed molecules alimohammadian with the catalyst surface. The reactor was purged with nitrogen as raising the temperature at 200 K per minute. After reaching a temperature of 773 K, the nitrogen was replaced by air and warmed up the catalyst at this temperature for 2-3 hours for grafting molecules alimohammadian to postanowi gasoline fraction at volumetric flow rates of the raw materials of 0.3 h-1and 0.6 h-1if the mileage of the catalyst in the reaction for 1 hour. On the surface of catalysate consistently applied to 0.5, 1.0, 1.5 and 2.0 wt.% a modifier. After each application of the modifier on the surface of the catalyst was regenerated from the coke deposits and inflicted on the regenerated catalyst to the next portion of lomographische. Experiments on the reforming of gasoline fractions was carried out on the modified catalysts in the above-mentioned conditions. The results of the experiments are shown in Fig. 1 and 2, which show respectively the effect of the concentration of lomographische on the octane number of the catalyst and the effect of the concentration of lomographische to the exit of the catalyst. This shows that the maximum activity has a mixture of catalysts, activated, 1.0 to 1.5 wt.% alimohammadian. Under identical conditions of this mixture of catalysts receive produce, having the octane number by the motor method for 2-4 points higher than the original mixture of catalysts without modification. Increases by 1.5-2.5% abs. the resultant catalysate with high octane number.

1. A method of processing low-octane gasoline fractions by atmospheric catalytic reforming is ridderzaal catalyst C-10 and aluminoborosilicate oxide catalyst.

2. The method according to p. 1, characterized in that a mixture of catalysts containing about 30. % zeolite catalyst C-10 and 70 vol.% alumnirelations oxide catalyst.

3. The method according to PP.1 and 2, characterized in that the process is carried out at a temperature of 753 - 773 K, the volumetric feed rate of the raw material 0,3 - 0,6 h-1.

4. The method according to PP.1 to 3, characterized in that a mixture of catalysts modified by lomographische, preferably in quantities of 1.0 to 1.5 wt.% from the mixture.

 

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SUBSTANCE: high-octane fuels and propane-butane fraction are obtained via conversion of hydrocarbon feedstock on contact with hot catalyst placed in reactor, into which diluting gas is supplied at elevated pressure. Catalyst is Pentasil-type zeolite with general formula xM2/nO,xAl2O3,ySiO2,zMe2/mO wherein M represents hydrogen and/or metal cation, Me group II or VII metal, n is M cation valence, m is Me metal valence, x, y, z are numbers of moles of Al2O3, SiO2, and Me2/mO, respectively, and y/x and y/z ratios lie within a range of 5 to 1000. Metal oxide Me2/mO is formed during calcination, in presence of oxygen, of Me-containing insoluble compound obtained in zeolite reaction mixture.

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11 cl, 4 dwg, 3 tbl, 16 ex

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18 cl, 3 dwg, 9 ex

FIELD: petroleum processing and petrochemistry.

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4 cl, 1 dwg, 1 tbl

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2 tbl, 9 ex

FIELD: petrochemical processes.

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7 cl, 2 tbl, 7 ex

FIELD: CHEMISTRY.

SUBSTANCE: zeolite catalyst for process of conversion of straight-run gasoline to high-octane number component is described. The said catalyst contains high-silica zeolite with SiO2/Al2O3=60 and residual content of Na2О of 0.02 wt.% maximum, metal-modified, Pt, Ni, Zn or Fe metals being in nanopowder form. Content of the said metals in the catalyst is 1.5 wt.% maximum. Method to manufacture zeolite catalyst for conversion of straight-run gasoline to high-octane number component is described. The said method implies metal modification of zeolite, Pt, Ni, Zn or Fe metals being added to zeolite as nanopowders, produced by electric explosion of metal wire in argon, by dry pebble mixing in air at room temperature. Method to convert straight-run gasoline using the said catalyst is also described.

EFFECT: increase in catalyst activity and gasoline octane number, accompanied by increase in yield.

4 cl, 3 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: invention describes zeolite-containing catalyst for transformation of aliphatic hydrocarbons C2-C12 to a mix of aromatic hydrocarbons or high-octane gasoline component containing zeolite ZSM-5 with silicate module SiO2/Al2O3=60-80 mol/mol and 0.02-0.05 wt % of residual sodium oxide content, zeolite structural element, promoter and binding component, with zirconium or zirconium and nickel oxides as zeolite structural component, and zinc oxide as promoter, at the following component ratio (wt %): zeolite 65.00-80.00; ZrO2 1.59-4.00; NiO 0-1.00; ZnO 0-5.00; Na2O 0.02-0.05, the rest being binding component. Also, a method for obtaining zeolite-containing catalyst is described, which involves mixing reagents, hydrothermal synthesis, flushing, drying and calcinations of sediment. The reaction mix of water solutions of aluminum, zirconium and nickel salts, sodium hydroxide, silicagel and/or aqueous silicate acid, inoculating zeolite crystals with ZSM-5 structure in Na or H-form, and structure-former, such as n-butanol, is placed in an autoclave, where hydrothermal synthesis is performed at 160-190°C for 10-20 hours with continuous stirring; the hydrothermal synthesis over, Na-form pulp of the zeolite is filtered; the obtained sediment is flushed with domestic water and transferred to salt ion exchange by processing by water ammonium chloride solution with heating and stirring of the pulp; the pulp obtained from salt ion exchange is filtered and flushed with demineralised water with residual sodium oxide content of 0.02-0.05 wt % on the basis of dried and calcinated product; flushed sediment of ammonium zeolite form proceeds to zinc promoter introduction and preparation of catalyst mass by mixing of ammonium zeolite form modified by zinc and active aluminum hydroxide; obtained catalyst mass is extruded and granulated; the granules are dried at 100-110°C and calcinated at 550-650°C; calcinated granules of zeolite-containing catalyst are sorted, ready fraction of zeolite-containing catalyst is separated, while the granule fraction under 2.5 mm is milled into homogenous powder and returned to the stage of catalyst mass preparation. The invention also describes method of transformation of aliphatic hydrocarbons to high-octane gasoline component or a mix of aromatic hydrocarbons (variants), involving heating and passing raw material (gasoline oil fraction direct sublimation vapours or gas mix of saturated C2-C4 hydrocarbons) through stationary layer of the aforesaid catalyst.

EFFECT: reduced number of components and synthesis stages of zeolite-containing catalyst; increased transformation degree of raw material; improved quality and yield of target products with the said catalyst.

4 cl, 8 tbl, 12 ex

FIELD: chemistry.

SUBSTANCE: invention refers to production method of high-octane gasoline fractions and/or aromatic hydrocarbons C6-C10 as follows, hydrocarbon materials is heated, evaporated and overheated to process temperature, thereafter providing its contact at temperature 320-480°C and excess pressure with periodically recyclable catalyst containing zeolite of composition ZSM-5 or ZSM-11. Then it is cooled. Contact products are partially condensed, separated into gaseous and liquid fractions by separation. Liquid products of separation are supplied as power primarily to the first distillation column for separation of hydrocarbon gases and liquid stable fraction. The latter is supplied to the second distillation column for separation of high-octane gasoline fraction, or aromatic hydrocarbon fraction, and heavy charge fraction. Gaseous fraction resulted from separation of contact products is supplied to the first distillation column, specifically to intermediate section between infeed and external reflux inlet. External reflux is liquid distillate of the first distillation column.

EFFECT: reduction of power inputs, i.e. quantities of heat and cooling agent, required for reaction products separation.

5 cl, 2 ex

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