WO2013149365A1

WO2013149365A1 - Method for producing gasoline blended component with high octane number

Info

Publication number: WO2013149365A1
Application number: PCT/CN2012/000747
Authority: WO
Inventors: 李潇; 罗琛; 胡雪生; 潘晖华; 张兆前; 马安; 李玮; 阎立军; 白跃华
Original assignee: 中国石油天然气股份有限公司
Priority date: 2012-04-05
Filing date: 2012-05-30
Publication date: 2013-10-10
Also published as: CN103361121A

Abstract

The present invention relates to a method for producing a gasoline blended component with a high octane number, comprising: raw materials of mixed C4-C8 alkane and C4 alkene entering an isomerization reaction device, and conducting an isomerization reaction in the presence of hydrogen with a catalytic reaction of an isomerization catalyst; an isomerization product generated after reaction flowing into a hydrogen separation device; mixing hydrogen obtained by separation and newly-added flesh hydrogen and then returning the mixed hydrogen to the isomerization reaction device; liquid hydrocarbon obtained by separation and the raw material heterogeneous C4 alkene entering an alkylation device; an alkylation product generated due to catalysis of an alkylation catalyst flowing into an alkylation catalyst recycling device, and C4-C6 light hydrocarbon, catalyst, and C8-C12 alkylation product streams being obtained by separation; the C4-C6 light hydrocarbon stream obtained by separation being exported as fuel gas or being recycled after separation; and one part of the catalyst steam obtained by separation being returned to the alkylation device, and the other part being discharged outside a boundary region. The method expands the source range of raw materials, and reduces the production cost. The octane number of the obtained alkylated oil reaches 91.5.

Description

Description Method for producing a high octane gasoline blending component

Technical field

The present invention pertains to a production process in the field of petroleum refining, and more particularly to a method for producing a high-octane value gasoline blending component.

Background technique

Gasoline quality standards are developing in the direction of lead-free, low aromatics, low vapor pressure, high sputum and high oxygen content. Isomerization and thiolation are widely used in petroleum refining processes to provide gasoline blending components that provide high sulphur values without increasing the aromatics content of gasoline.

The so-called isomerization is a reaction in which a normal terpene hydrocarbon is converted into an isomeric hydrocarbon by a catalytic reaction of a catalyst under a certain reaction condition. Due to the high knock resistance of isomerized terpene hydrocarbons, the octane number is higher than that of the corresponding normal terpene hydrocarbons, so it is a good high-octane gasoline blending component. At the same time, some of the isomeric hydrocarbons can also be used as raw materials for the thiolation process.

The so-called thiolation is a process in which anthracene hydrocarbons and olefins are reacted to form macromolecular isomeric hydrocarbons. Since the thiolized product tends to form a tertiary carbon and has many branches, it has good antiknock performance and high sputum value, and is a very good high-octane gasoline blending component. After years of development, a relatively mature production process has been formed.

Due to the increasingly poor raw material source and higher and higher oil quality requirements this year, the research on the above production process and the development of a new generation of catalysts are still products of the isomerization process in the hotspot of refining and chemicals. As a raw material for the thiolation process, a simple series of two processes like this is not uncommon. Since the two processes are connected in series, the process can be further simplified, the energy consumption is reduced, and the economic efficiency is improved to some extent. Some improvements in the process are not The work was reported by the work.

Part of the work seeks improvement in the separation process. For example, the patent CN200680015930.8 introduces a membrane separation process in the separation process of the C4 isomerization reaction product, which reduces the energy consumption, improves the separation efficiency, and helps to reduce the alkylation of the isomerization catalyst. The interference caused by the reaction part. However, this separation method is limited to the case where the composition of the feed is relatively simple, but it is not possible for a mixed feed such as C5-C6.

Part of the effort is to improve product selectivity and yield by improving the control of reaction conditions. A method for preparing a thiolated product in a downflow reactor is reported as patent CN200710161288.0. In this way, the olefin oligomer acts as an olefin precursor rather than an olefin in the reaction.

A small amount of work dedicated to integrating isomerization and thiolization projects does not deviate from the reliance on simpler raw materials, or the process of producing C4, especially C5 or higher light gasoline components as raw materials. Further optimization process. A combination of isomerization and guanidation processes is disclosed, for example, in U.S. Patent No. 7,439,410, but is limited to C3-C4 feedstocks. Because it may cause systemic problems such as the accumulation of inert components, it cannot be applied to raw materials above C5.

Summarizing the above improvements in the thiolation and isomerization processes, the following deficiencies exist:

1. Mainly for C4 raw materials. The advent of the alkylation process once found a good way out for refinery C4, and the thiolated oil that can be used as a blending component of high-octane gasoline has a much higher economic value than liquefied gas. Therefore, research work in this area tends to focus on the use of C4 components, while the C5-C6 components are only balanced.

2. Poor handling of mixed feeds. The existing process is only suitable for narrow fraction feeds and is not suitable for C4-C8 wide fraction mixed feeds. When processing the wide-distillate mixed feed, the unreacted raw materials are only partially utilized, the energy consumption is high, and the alkylated oil has a low Xining value. 3. The process is complex. Isomerization and alkylation are developed as two separate processes. Existing research often focuses on the research of existing devices and fails to work from the perspective of fundamentally integrating the two processes. Therefore, the process flow is still complicated.

As the number of carbon atoms increases, the number of isomers of hydrocarbons increases sharply from C6. For mixed feeds such as light gasoline components, the already mature processes for C4 isomerization and thiolation cannot be simply applied due to the complex types of components. In particular, the separation of normal terpene hydrocarbons from isomeric terpene hydrocarbons in the mixed component poses significant difficulties in separating the products of the isomerization process. Enrichment of certain inert components is also not available in the C4 process.

In response to the above problems, working only on a separate process will not help solve the problem. Integrating and improving from the source is a good idea.

Summary of the invention

SUMMARY OF THE INVENTION It is an object of the present invention to provide a process for the production of a high-octane-valued gasoline blending component comprising C4-C8 mixed terpene hydrocarbons and C4 olefins. The raw material is subjected to isomerization and thiolation to form a thiolated oil, and only unreacted hydrogen and a small amount of C3-C4 light components are simply separated. Make the process flow the most simple. In particular, to solve the problem of processing the mixed feed of the wide fraction, the reaction separation is used, and a small amount of unreacted raw materials can be recycled or directly into the product. Adapting to the actual production of the refinery, the source of raw materials is broadened and the production cost is greatly reduced. At the same time, the product has a high Xinxin value, which guarantees good economic benefits.

The C4-C8 terpene hydrocarbon feedstock should have an olefin content of less than 10%, an oxygenate of 50 ppm or less, and a sulfur content of less than 20 ppm. The C4-C8 mixed alkane and C4 olefin feed stream 101 enters the isomerization reactor 10. The isomerization reaction is carried out by catalytic reaction of an isomerization catalyst under hydrogen conditions. The catalyst is a supported catalyst of Group VIII metal, and the VIII noble metal is especially platinum. The loading is preferably from 0.01 to 5% by mass, based on at least 0.15% and not more than 0.50%. Containing one or more of the promoter metals, such as: tin, lead, iron, cobalt, tungsten, molybdenum, niobium, A mixture of copper, silver, cadmium, bismuth, or a plurality of rare earths having a mass fraction of 0.01 to: L%. The process conditions used are hydrogen partial pressure of 0. 5-2.5 MP3, temperature of 150-280 ° C, mass space velocity of 0.2-5.5 hours, hydrogen oil volume ratio of 400-600, system pressure of 4-12 MPa. The isomerized stream 102 formed by the reaction enters the hydrogen separation unit 20. The separated hydrogen stream 103 is separated from the supplemented fresh hydrogen 113 and returned to the isomerization unit 10. The resulting liquid hydrocarbon 104 and the starting material isomeric C4 olefin 105 are separated into the thiolation unit 30. The isobutylene content of the isomeric C4 olefin is greater than 75% and the sulfur content is less than 20 ppm. The alkylation stream 106 formed under the catalyzed by the thiolation catalyst enters the thiolation catalyst recovery unit 40. A C4-C6 light hydrocarbon 107, catalyst 108, C8-C12 thiolated product stream 109 is isolated. The resulting C4-C6 light hydrocarbon stream 107 is separated for gas or recycled for recycling. A portion 116 of the separated catalyst stream is separated back to the thiolation unit 30 and another portion 115 is out of bounds. The thiolation catalyst is one of sulfuric acid, hydrofluoric acid or a chlorine-containing solid acid, the acid to hydrocarbon ratio is 1.45; and the reaction temperature is -10 to 25 °C.

For the product to be refined, as shown in Fig. 2, the thiolated product stream 109 separated in the thiolated catalyst recovery unit 40 is passed to the light hydrocarbon recovery section 50. The resulting heavier C8-C12 sulfhydryl oil stream 112 is separated as a product outbound zone. A portion 118 of the resulting lighter C5-C7 hydrazine-rich hydrocarbon stream 111 is separated back to the isomerization unit 10, and another portion 117 is out of bounds.

As shown in FIG. 3, the supplemental thiolation catalyst stream 119 is premixed with the recycle catalyst stream 116 and passed to the thiolation reactor 30.

For special requirements on the product, as shown in Figure-4, the heavier C8-C12 sulfhydryl oil stream 112 separated in the light hydrocarbon recovery unit 50 is part of the product demarcation zone, and the other part is recirculated by the reboiler 52. Light hydrocarbon recovery unit 50. A portion 118 of the resulting lighter C5-C7 hydrocarbon-rich stream 111 is separated back to the isomerization unit 10 and another portion is passed to the condenser 51. After condensation, the non-condensable gas 124 delivers gas, a portion of the condensate 122 is returned to the light hydrocarbon recovery unit 50, and another portion 123 is sent to the boundary zone. DRAWINGS

Figure 1 Flow chart of the production method

Figure 1 Product simple refining process

Figure 3 catalyst supplement

Figure 4 Product deep refining process

Example 1

In order to verify the effect of the present invention, an industrial experiment was carried out on an experimental apparatus using the process flow shown in Fig. 1.

The raw materials used in this experiment were light gasoline fractions and isomeric carbon tetraolefins in straight-run gasoline of a petrochemical company. The typical properties of raw material straight-run light gasoline are shown in Table-1. The composition of the isomeric carbon tetraene is: isobutylene 91%, other carbon tetraolefins 9%.

Table -1 Typical properties of a petrochemical company's straight-run light gasoline

The process conditions employed were that the isomerization unit had a hydrogen partial pressure of 1.8 MPa, a temperature of 270 ° C, a space velocity of 1.2 hours - a hydrogen oil volume ratio of 520, and a system pressure of 5.5 MPa. Alkylation Part of the catalyst was sulfuric acid, the reaction temperature was 12 ° C, the reaction pressure was 0.55 MPa, and the acid to hydrocarbon ratio was 1.45. The alkylated oil obtained from the experiment had an octane number of 88.9. Example 2

The thiolated oil obtained in Example 1 was simply purified, and a refining experiment was carried out on an experimental apparatus by using the process shown in Fig. 2. The experimental temperature was 75 ° C, the experimental pressure was 50 kPa, and the experimental sulfhydryl oil research octane number was 91.5.

Example 3

In order to verify the effects of the present invention, an industrial experiment was conducted on an experimental apparatus using the process flow shown in Fig. 4.

The raw materials used in this experiment are a petrochemical company, pentamidine oil and isomeric carbon tetraene. The properties of the raw material eucalyptus oil are shown in Table-2. The composition of the isomeric carbon tetraene is: isobutylene 91%, other carbon tetraolefins 9%.

Table -2 The nature of a petrochemical company

The process conditions used are that the isomerization unit has a hydrogen partial pressure of 1.8 MPa and a temperature of 270 ° C. The mass space velocity is 1.2 hours 3⁄4 汕 volume ratio is 520, and the system pressure is 5.5 MPa. The alkylation part of the catalyst was sulfuric acid, the reaction temperature was 12 ° C, the reaction pressure was 0.55 MPa, and the acid to hydrocarbon ratio was 1.45. The experimental sulfhydryl oil research octane number was 91.5.

Industrial Applicability The method disclosed in the present invention faces a C5-C6 terpene hydrocarbon on a raw material, and takes into consideration C4 hydrocarbon. The raw material is passed through an isomerization and alkylation process to form an alkylated oil, in which only unreacted hydrogen and a small amount of C3-C4 light components are simply separated. Make the process flow the most simple. In particular, to solve the problem of processing the mixed feed of the wide fraction, the reaction separation is carried out, and a small amount of unreacted raw materials can be recycled or directly into the product. Adapting to the actual production of refineries, it has broadened the source of raw materials and greatly reduced production costs. At the same time, the product has a high value of bismuth-based oil, which guarantees good economic benefits.

Claims

Rights request

A method for producing a high-octane value gasoline blending component, characterized by:

1) The C4-C8 mixed terpene hydrocarbon and the C4 olefin raw material enter the isomerization reaction device, and the isomerization reaction is carried out by catalytic reaction of the isomerization catalyst under hydrogen condition;

2) the isomerization stream formed by the reaction enters the hydrogen separation unit;

3) the separated hydrogen is mixed with the supplemented fresh hydrogen and returned to the isomerization reaction device;

4) separating the obtained liquid hydrocarbon and the raw material isomerized C4 olefin into the thiolation device;

5) the thiolation stream formed by the alkylation catalyst is introduced into the thiolation catalyst recovery device to separate the C4-C6 light hydrocarbon, the catalyst, and the C8-C12 thiolated product stream;

6) Separating the obtained C4-C6 light hydrocarbon stream to the gas or recycling it for recycling;

7) A portion of the separated catalyst stream is returned to the thiolation unit and another portion of the demarcation zone.

2. The method for producing a high-octane-value gasoline blending component according to claim 1, wherein: the thiolated product stream separated in the thiolated catalyst recovery unit is passed to a light hydrocarbon recovery portion; and the obtained C5- is separated. A portion of the C7 hydrazine hydrocarbon stream is returned to the isomerization reactor, and another portion of the demarcation zone is separated; the resulting C8-C12 thiolated product stream is separated as the product outbound zone.

3. A process for the production of a high gamma value gasoline blending component according to claim 1 wherein the additional thiolated catalyst stream is premixed with the recycle catalyst stream and passed to an alkylation reactor.

4. The method for producing a high-octane-valued gasoline blending component according to claim 1, wherein: a portion of the mercaptosulfide stream separated in the light hydrocarbon recovery unit is used as a product outbound zone, and another portion is subjected to a reboiler. Returning light hydrocarbon recovery unit; separating a part of the obtained C5-C7 hydrazine hydrocarbon stream back to the isomerization reaction device, and another part into the condenser; after condensing, the gas is not condensed, and the condensate is partially returned to the light hydrocarbon recovery device, Part of it is sent out of the precinct.

5. The method for producing a high-octane-valued gasoline blending component according to claim 1, characterized in that The catalyst for isomerization is a silicon or aluminum supported platinum catalyst, and the platinum loading mass fraction is 0.01 to 5% of the catalyst.

6. The method for producing a high-octane-valued gasoline blending component according to claim 1, wherein the promoter for the isomerization reaction is tin, lead, iron, cobalt, tungsten, molybdenum, ruthenium, copper, silver. , cadmium, bismuth or a mixture of various rare earths, the mass percentage being 0.01~: L% of the catalyst.

The mass fraction of the isomerization reaction is 0. 5~2.5MPa, the temperature is 150~280°C, the quality is as follows. The space velocity is 0.2 to 5.5 hours - the hydrogen oil volume ratio is 400 to 600, and the system pressure is 4 to 12 MPa.

The method for producing a high-octane gasoline blending component according to claim 1, wherein the alkylation catalyst is one of sulfuric acid, hydrofluoric acid or a chlorine-containing solid acid, and the acid to hydrocarbon ratio is 1.45.

The method for producing a high-octane-value gasoline blending component according to claim 1, wherein the thiolation reaction temperature is from -10 to 25 °C.