CN107151562A - A kind of method of liquefied gas esterification production high-knock rating gasoline blend component - Google Patents

Abstract

The invention provides a method for producing high-octane gasoline blending components through esterification of liquefied gas. The method comprises the following steps: mixing the liquefied gas and the organic acid in a certain proportion, sending them into an esterification reactor equipped with an esterification catalyst after being heated, so that the olefins and organic acids in the liquefied gas are generated under the action of the esterification catalyst Esterification reaction; then the esterification product is sent to the rectification system for separation to obtain high-quality liquefied gas with low olefin content and esters with high octane number. The method can obtain high-octane esters while reducing the olefin content in the liquefied gas, and can be used for the production of high-octane blending components.

Description

A method for producing high-octane gasoline blending components through esterification of liquefied gas

technical field

The invention relates to a method for producing high-octane gasoline blending components through esterification of liquefied gas; specifically, a method for converting low-value-added liquefied gas into high-octane esters, and the ester mixture produced by the reaction The blending component that can be used for finished gasoline belongs to the technical field of producing gasoline from liquefied gas in the field of petroleum refining.

Background technique

With the development of the oil refining industry, various refineries produce a considerable amount of liquefied gas in the process of oil refining, which contains rich C3 and C4 alkanes and olefins, and may also have a small amount of C2 and C5 hydrocarbons. At present, most refineries sell this part of liquefied gas as fuel, resulting in a waste of resources. The liquefied gas-to-gasoline technology can effectively use low-value-added liquefied gas to produce high-octane gasoline, which is a very meaningful way of resource utilization and can significantly increase the economic benefits of refineries.

CN102851063A discloses a method for producing high-octane clean gasoline by aromatizing dry gas and liquefied gas. The method utilizes a fixed-bed reactor, and a liquefied gas aromatization catalyst is loaded in the upper section, and a dry gas aromatization catalyst is filled in the lower section. ; The liquefied gas enters from the top of the reactor, and the aromatization reaction occurs in the upper section of the reactor, and the dry gas enters between the packed beds of the reactor, and the dry gas aromatization reaction occurs in the lower section of the reactor; the finally obtained aromatic oil is separated The system gets gasoline with an octane rating of up to 97.5 (RON).

CN101875851A discloses a method for non-hydrogen-facing upgrading of liquefied gas fractions. In this method, the liquefied gas raw material is divided into multiple streams, which respectively enter a plurality of series-connected upgrading reaction zones, and the superposition and isomerization of olefins occur in contact with the reformed catalyst. As well as the aromatization reaction, after the gas-liquid separation of the obtained product, part of the gas phase stream is recycled to the reaction system, and the remaining gas phase stream and liquid phase stream are used as vehicle liquefied gas blending components and gasoline blending components respectively. This method solves the problems of high catalyst bed temperature and difficult control of reaction heat when only liquefied gas is used as raw material for non-hydrogen upgrading, and the octane number of the obtained gasoline blending components can reach 90 (RON).

CN103509600A discloses a method for producing high-octane gasoline blending components by aromatization of mixed carbon four, which involves aromatizing mixed carbon four in a fixed-bed reactor to produce high-octane gasoline blending components At the same time, the isobutane that does not participate in the reaction in the raw material and the isobutane generated by the aromatization reaction are converted into olefins through catalytic dehydrogenation, and are mixed with C4 to carry out the aromatization reaction before being recycled to the aromatization reactor. The method increases the total amount of olefins participating in the aromatization reaction, improves the yield of octane gasoline blending components and the effect of the aromatization reaction.

CN102690677A discloses a method for producing high-octane clean gasoline by combining liquefied gas alkane aromatization and olefin aromatization. The method uses two-stage catalyst beds, the upper end is filled with an alkane aromatization catalyst, and the lower end is filled with an olefin aromatization catalyst. Catalyst; the liquefied gas raw material is fed between the two-stage catalysts, mixed with the alkane aromatization product, and then enters the lower bed; after the reaction product is separated, the obtained gasoline is sent to the gasoline stabilization system, and the obtained olefin-depleted liquefied gas is partially returned to the The upper stage reactor carries out the alkane aromatization reaction. In the method, both olefins and alkanes in the liquefied gas can be converted into the target product gasoline, the gasoline yield can reach 60%, and the gasoline octane number is as high as 93 (RON).

CN101538479A discloses a method for producing alkylated oil by low-temperature hydroalkylation of carbon tetraolefins, in which the mixed carbon tetraolefins are passed into a fixed-bed reactor equipped with a zeolite molecular sieve catalyst under hydrogen conditions to undergo alkylation In the reaction, the liquid yield of carbon five or more in the obtained product is as high as 75%, the sum of straight-chain alkanes and branched-chain alkanes is as high as 61%, and the octane number of the liquid phase oil is more than 93.6 (RON).

CN103361121A discloses a production method of high-octane gasoline blending components. The method uses C4-C8 mixed alkanes and C4 olefins as raw materials, and sequentially passes through an isomerization reactor and an alkylation reactor, and the obtained product is separated. , C4-C6 light hydrocarbon gas delivery system or the inlet of the isomerization reactor for recycling, and the remaining stream is used as the alkylated gasoline product out of the boundary area. The method has simple process and flexible operation, and the octane number of the alkylated gasoline product can reach 91.5 (RON).

To summarize the above-mentioned high-octane methods for liquefied gas or C4 olefins, mainly through aromatization or isomerization. Although these two methods can obtain high-octane gasoline, the aromatization reaction temperature is high and energy consumption is high. It is relatively large and has high requirements for equipment; the isomerization reaction catalyst is easily deactivated, and the single-pass service life is short, which is not conducive to long-term operation.

Contents of the invention

In order to solve the above-mentioned technical problems, the object of the present invention is to provide a method for producing high-octane gasoline blending components through esterification of liquefied gas. The method can obtain high-octane esters while reducing the olefin content in the liquefied gas, and can be used for the production of high-octane gasoline blending components.

In order to achieve the above object, the invention provides a method for esterifying liquefied gas to produce high-octane gasoline blending components, the method comprising the following steps:

The liquefied gas and organic acid are mixed in a certain proportion, heated and sent to the esterification reactor equipped with an esterification catalyst, so that the olefins (generally C3-C4 olefins) and organic acids in the liquefied gas can react with the esterification catalyst Under the esterification reaction;

Then the esterification product is sent to the rectification system for separation to obtain high-quality liquefied gas with low olefin content and esters with high octane number.

In the above-mentioned production method, preferably, the liquefied gas is liquefied gas directly produced by one or several upstream thermal cracking, coking and catalytic cracking units. The liquefied gas is a liquefied gas with a high olefin content, and the olefin content is 10-95 wt%.

In the above production method, preferably, the organic acid includes one or a combination of compounds with the following general structural formula:

In the formula, R is any one of H, CH ₃ , C ₂ H ₅ , and C ₃ H ₇ .

In the above production method, the ratio of the liquefied gas to the organic acid is determined according to the olefin content in the liquefied gas. Preferably, the amount of the organic acid should be such that the olefin and organic acid in the liquid stream after the liquefied gas is mixed with the organic acid The volume ratio of organic acid is 0.5-2:1.

In the above production method, preferably, the esterification catalyst has high secondary ester selectivity, which includes metal oxide catalysts, zeolite molecular sieve catalysts, SO ₄ ^2- /M _x O _y catalysts, and strongly acidic cation exchange resin catalysts, etc. Among them, preferably, the metal oxide catalyst can include ZnO, SnO and Al ₂ O ₃ supported by at least one of silicon oxide, molecular sieve and diatomaceous earth, etc. A catalyst made of at least one metal oxide, and the carrier may have a mesoporous structure;

The zeolite molecular sieve catalyst may include one or more mixed molecular sieve catalysts of aluminum phosphate molecular sieve, silicoaluminophosphate molecular sieve, H-type mordenite, HY zeolite, H-beta zeolite and HZSM-5 zeolite, etc., and the The zeolite molecular sieve can be a step-pore zeolite molecular sieve;

_The SO ₄ ^2- /M _x O _y catalyst may include SO ₄ ^2- supported on a carrier made of at least one metal oxide among ZrO, ZnO and SnO, ^etc. _x O _y catalyst, and the metal oxide can be a mesoporous metal oxide;

The strongly acidic cation exchange resin catalyst may include a meso-macroporous polymer cross-linked polymer catalyst containing a strongly acidic reactive group (such as sulfonic acid group-SO ₃ H, etc.).

In the above production method, preferably, the conditions of the esterification reaction are: temperature 80-200°C, pressure 1-60atm, liquid volume space velocity 0.5-10h ^-1 (calculated as organic acid).

In the above production method, preferably, the esterification reactor is a fixed-bed esterification reactor.

In the above production method, preferably, according to the composition of the liquefied gas and the esterification product, the rectification system can be a rectification system composed of two or more rectification towers. When performing rectification in the rectification system, the first rectification tower can be used to separate high-quality liquefied gas with low olefin content, and the top pressure of the rectification tower can be controlled at 1-10 atm, and the top temperature can be controlled Control at 20-70°C, the pressure of the tower bottom can be controlled at 1-10atm, the temperature of the tower bottom can be controlled at 100-200°C, the reflux ratio can be controlled at 0.1-10; The mixture of the mixture is further rectified, and water can be used as entrainer in this rectification process, the mol ratio of the mixture of esters and organic acid and entrainer water can be 1-5:1, the rectification column The pressure at the top of the tower can be controlled at 1-10atm, the temperature at the top of the tower can be controlled at 50-90°C, the pressure at the bottom of the tower can be controlled at 1-10atm, the temperature at the bottom of the tower can be controlled at 90-150°C, and the reflux ratio can be controlled at 0.1-5 ; Then the mixture of the obtained esters and a small amount of water can be phase-separated to obtain high-octane esters; at the same time, the mixture of organic acids and water obtained can be further rectified by using the third rectification column , the top pressure of the rectification tower can be controlled at 1-10atm, the top temperature can be controlled at 80-120°C, the bottom pressure can be controlled at 1-10atm, the bottom temperature can be controlled at 100-150°C, the reflux ratio It can be controlled at 0.1-5, and the obtained organic acid can be recycled as a raw material for esterification reaction, and the obtained water can be recycled as an entrainer together with the water obtained by phase separation. In addition, the rectification towers in the above-mentioned rectification system can all use packed towers. Compared with plate towers, packed towers have many advantages such as high mass transfer flux, large processing capacity, low pressure drop, and low overall cost. The packing can include θ ring, Pall ring, Raschig ring, etc.

In the above production method, preferably, the olefin content of the obtained high-quality liquefied gas with low olefin content is 5-40v%, and the research octane number of the esters with high octane number is 100-130.

The invention provides a method for producing high-octane gasoline blending components through esterification of liquefied gas, which can obtain high-octane esters while reducing the content of olefins in liquefied gas, and can be used for high-octane Production of gasoline blending components. At the same time, the method for high-octane liquefied gas provided by the present invention adopts esterification reaction, the reaction conditions of the esterification reaction are mild, the requirements for equipment are not high, and the service life of the esterification catalyst is long, so the aromatization reaction temperature is overcome. The defects of relatively high energy consumption, high requirements for equipment, easy deactivation of isomerization reaction catalyst, short service life of one pass, and unfavorable long-term operation provide an effective and feasible method for the field of liquefied gas to gasoline new technology.

Description of drawings

Fig. 1 is the technological process schematic diagram of embodiment 1, embodiment 2, embodiment 3 and embodiment 4.

detailed description

In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is described in detail below, but it should not be construed as limiting the scope of implementation of the present invention.

Example 1

This example provides a method for producing high-octane gasoline blending components by esterification of liquefied gas with high olefin content (ie model gas 1). The composition of model gas 1 is shown in Table 1.

Wherein, based on the total weight, the composition ratio of the esterification catalyst is: 40wt% HZSM-5, 60wt% Al ₂ O ₃ —SiO ₂ (namely silicon-containing alumina).

The concrete preparation steps of esterification catalyst are as follows:

Mix deionized water, sodium hydroxide, aluminum nitrate, ethyl orthosilicate and tetrapropylammonium hydroxide in a molar ratio of 150:2:2.5:20:5, and stir evenly to obtain a mixed system of starting sol, Then add polyquaternary ammonium PCD (the molar ratio of polyquaternium PCD to aluminum nitrate is 0.3:1), stir evenly; age at 50°C for 24h; crystallize at 170°C for 72h; The resulting product was cleaned, separated, dried, and calcined at 550°C for 5 hours to obtain the stepped pore ZSM-5.

Mix the above-mentioned stepped pore ZSM-5 zeolite with 1mol/L NH ₄ Cl solution at a weight ratio of 1:10, stir at 80°C for 4h, filter, wash, dry, and roast at 550°C for 5h; repeat the above steps once to obtain ammonium exchange The step-pore HZSM-5 zeolite.

Weigh 30g of silica-alumina powder (containing Al ₂ O ₃ 92.0wt%, SiO 8.0wt%), 20g of the above-mentioned stepped pore HZSM-5 zeolite and 1.9g of squid powder, grind and mix evenly, add 4.5mL of 65wt% nitric acid solution, Fully kneaded, then molded on an extruder, dried at 120°C for 4 hours, and calcined at 550°C for 5 hours to obtain a clover-shaped transesterification catalyst with a diameter of 2mm.

The process of producing high-octane gasoline blending components by esterification with model gas 1 as raw material is as follows, and the process flow is shown in Figure 1:

First, stream 1 (i.e. model gas 1) and stream 2 (i.e. acetic acid) are mixed at a volume ratio of 1.6:1 to form stream 3. After being heated, stream 3 is sent to fixed-bed esterification reactor 101, where it contacts with the esterification catalyst. Esterification reaction, the reaction conditions are: pressure 20atm, temperature 120°C, liquid volume space velocity 3h ^-1 (calculated as acetic acid);

The stream 4 obtained after the esterification reaction is sent to the first rectification tower 102 for separation to obtain the overhead stream 5 (i.e. high-quality liquefied gas with low olefin content) and the bottom stream 6 (i.e. the mixture of esters and acetic acid) ; The first rectifying tower 102 adopts packed tower, and packing is the stainless steel θ ring of 2.5 * 2.5mm, and theoretical plate number is 39, and feed plate number is 20, and reflux ratio is 1, tower top pressure 5atm, tower still pressure 5.27atm, tower top The temperature is 54.2°C, and the temperature of the tower kettle is 187.5°C;

Stream 6 and stream 7 (being water) are sent into the second rectifying tower 103 with the molar ratio of 2.75:1 and are separated, obtain tower top stream 9 (being esters and a small amount of water) and tower bottom stream 8 (being water and acetic acid ); The second rectifying tower 103 adopts packed tower, and packing is the stainless steel θ ring of 2.5 * 2.5mm, and theoretical plate number is 35, and feed plate number is 20, and reflux ratio is 3.5, tower top pressure 1atm, tower still pressure 1.24atm, tower The top temperature is 76.6°C and the bottom temperature is 119.7°C;

Stream 9 is sent to phase separation system 104 to obtain stream 14 (i.e. high-octane esters) and stream 12 (i.e. water). The operating conditions of phase separation system 104 are: pressure 1atm, temperature 30°C;

Stream 8 is sent to the third rectification tower 105 and separates, and obtains tower top stream 11 (being water) and tower bottom stream 10 (being acetic acid), and the third rectification tower 105 adopts packed tower, and packing is the stainless steel of 2.5 * 2.5mm θ ring, the number of theoretical plates is 44, the number of feeding plates is 26, the reflux ratio is 15, the pressure at the top of the tower is 1 atm, the pressure at the bottom of the tower is 1.30 atm, the temperature at the top of the tower is 99.7°C, and the temperature at the bottom is 125.9°C;

After the stream 11 is mixed with the stream 12, the stream 13 is obtained, and the stream 13 is mixed with the stream 7, and continues to enter the second rectifying tower 102 as an entrainer;

Stream 10 is mixed with stream 2 to obtain stream 15, which continues to be used as acetic acid raw material and enters fixed-bed esterification reactor 101.

See Table 1 for the composition of model gas 1, liquefied gas after esterification and ester products.

Table 1 Composition of model gas 1, liquefied gas and ester products after esterification

composition Conversion rate,% model gas 1 LPG after esterification Esters Propane, v% - 17.0 28.0 - Propylene, v% 73.0 18.0 8.0 - Butane, v% - 12.0 19.8 - Butene, v% 65.2 40.0 22.9 - Pentane, v% - 13.0 21.3 - Isopropyl acetate, v% - - - 33.5 sec-butyl acetate, v% - - - 66.5 Research Octane Number (RON) 121.0

Using the method provided in this example to carry out esterification of liquefied gas, acetic acid and entrainer (i.e. water) can be reused, avoiding the discharge of waste liquid; as can be seen from Table 1, the conversion rates of propylene and butene in the liquefied gas are respectively It is 73.0% and 65.2%. While reducing the olefin content in liquefied gas, an ester mixture with high octane number is produced. The research method octane number is as high as 121.0, which can be used for gasoline blending components.

Example 2

This example provides a method for producing high-octane gasoline blending components through esterification of liquefied gas with high olefin content (model gas 1).

The composition and preparation method of esterification catalyst are:

Dissolve 10.0 g of zirconium chloride in 50 mL of ethanol, add 3.0 g of sodium dodecyl sulfate (SDS), drop 30 wt % of ammonia water therein at 50 ° C, adjust the pH of the solution to 6.0, and obtain Zr(OH) ₄ sol; the above sol was gelled at 80°C for 12 hours to obtain ZrO ₂ gel; the ZrO ₂ gel was dried at 90°C for 12 hours, and fired at 500°C for 5 hours to remove the template agent to obtain mesoporous ZrO ₂ ; 120-mesh sieve, immerse the sieved product in 100mL 2mol/L ammonium sulfate solution for 1h, filter, wash, dry, and roast at 600°C for 4h to obtain SO ₄ ^2- /ZrO ₂ catalyst.

The process of carrying out esterification with model gas 1 as a raw material to produce high-octane gasoline blending components is the same as in Example 1, and its technological process is as shown in Figure 1; the difference is the operating conditions of each rectifying tower:

The first rectification column 102 adopts a packed tower, and the filler is a stainless steel θ ring of 2.5×2.5 mm, with a theoretical plate number of 31, a feed plate number of 16, a reflux ratio of 1, a tower top pressure of 5 atm, a tower bottom pressure of 5.21 atm, and a tower top temperature of 27.5°C, the temperature of the tower kettle is 189.1°C;

The second rectifying column 103 adopts a packed tower, and the filler is a stainless steel θ ring of 2.5 × 2.5mm, with a theoretical plate number of 35, a feed plate number of 15, a reflux ratio of 3, a tower top pressure of 1 atm, a tower bottom pressure of 1.24 atm, and a tower top temperature of 1 atm. 76.7°C, the temperature of the tower kettle is 102.5°C;

The third rectifying column 105 adopts a packed tower, and the packing is a stainless steel θ ring of 2.5×2.5 mm, with 48 theoretical plates, 27 feed plates, a reflux ratio of 3.5, a tower top pressure of 1 atm, a tower bottom pressure of 1.33 atm, and a tower top temperature 99.7°C, the temperature of the tower kettle is 110.8°C;

See Table 2 for the composition of model gas 1, liquefied gas after esterification and ester products.

Table 2 Composition of model gas 1, liquefied gas and ester products after esterification

composition Conversion rate,% model gas 1 LPG after esterification Esters Propane, v% - 17.0 26.8 - Propylene, v% 68.0 18.0 9.1 - Butane, v% - 12.0 18.9 - Butene, v% 60.0 40.0 25.2 - Pentane, v% - 13.0 20.0 - Isopropyl acetate, v% - - - 33.8 sec-butyl acetate, v% - - - 66.2 Research Octane Number (RON) 121.0

It can be seen from Table 2 that the conversion rates of propylene and butene in the liquefied gas are 68.0% and 60.0% respectively. While reducing the olefin content in the liquefied gas, an ester mixture with a high octane number is produced. The research method The octane number is as high as 121.0, which can be used in gasoline blending components.

Example 3

This example provides a method for producing high-octane gasoline blending components by esterifying liquefied gas (model gas 2) with high olefin content. The composition of model gas 2 is shown in Table 3.

The composition of esterification catalyst and preparation method are identical with embodiment 1;

The process of carrying out esterification with model gas 2 as a raw material to produce high-octane gasoline blending components is the same as in Example 1, and its technological process is as shown in Figure 1; the difference is the operating conditions of each rectifying tower:

The first rectification column 102 adopts a packed tower, the packing is a stainless steel θ ring of 2.5×2.5 mm, the number of theoretical plates is 38, the number of feed plates is 20, the reflux ratio is 1, the pressure at the top of the tower is 5 atm, the pressure at the bottom of the tower is 5.26 atm, and the temperature at the top of the tower is 26.1°C, the temperature of the tower kettle is 194.4°C;

The second rectifying tower 103 adopts a packed tower, and the filler is a stainless steel θ ring of 2.5 × 2.5mm, with a theoretical plate number of 35, a feed plate number of 15, a reflux ratio of 3.5, a tower top pressure of 1 atm, a tower bottom pressure of 1.24 atm, and a tower top temperature 77.2°C, the temperature of the tower kettle is 108.2°C;

The third rectifying column 105 adopts a packed tower, and the filler is a stainless steel θ ring of 2.5 × 2.5mm, the number of theoretical plates is 47, the number of feed plates is 27, the reflux ratio is 4, the pressure at the top of the tower is 1 atm, the pressure at the bottom of the tower is 1.32 atm, and the temperature at the top of the tower is 1 atm. 99.7°C, the temperature of the tower kettle is 126.2°C;

See Table 3 for the composition of model gas 2, liquefied gas after esterification and ester products.

Table 3 Composition of model gas 2, liquefied gas and ester products after esterification

composition Conversion rate,% model gas 1 LPG after esterification Esters Propane, v% - 22.0 34.1 - Propylene, v% 74.8 15.0 5.9 - Butane, v% - 16.0 24.8 - Butene, v% 67.8 30.0 15.0 - Pentane, v% - 17.0 20.2 - Isopropyl acetate, v% - - - 35.5 sec-butyl acetate, v% - - - 64.5 Research Octane Number (RON) 121.3

It can be seen from Table 3 that the conversion rates of propylene and butene in the liquefied gas are 74.8% and 67.8% respectively. While reducing the olefin content in the liquefied gas, an ester mixture with a high octane number is produced. The research method The octane number is as high as 121.3, which can be used in gasoline blending components.

Example 4

This example provides a method for producing high-octane gasoline blending components through esterification of liquefied gas with high olefin content (model gas 2).

The composition of esterification catalyst and preparation method are identical with embodiment 2;

The process of carrying out esterification with model gas 2 as a raw material to produce high-octane gasoline blending components is the same as in Example 1, and its technological process is as shown in Figure 1; the difference is the operating conditions of each rectifying tower:

The first rectification column 102 adopts a packed tower, and the filler is a stainless steel θ ring of 2.5 × 2.5 mm, with a theoretical plate number of 38, a feed plate number of 20, a reflux ratio of 1, a tower top pressure of 5 atm, a tower bottom pressure of 1.26 atm, and a tower top temperature of 26.0°C, the temperature of the tower kettle is 196.6°C;

The second rectifying column 103 adopts a packed tower, and the filler is a stainless steel θ ring of 2.5 × 2.5 mm, with a theoretical plate number of 35, a feed plate number of 15, a reflux ratio of 4, a top pressure of 1 atm, a pressure of the tower bottom of 1.24 atm, and a temperature of the top of the tower 77.6°C, the temperature of the tower kettle is 108.6°C;

The third rectifying column 105 adopts a packed tower, and the filler is a stainless steel θ ring of 2.5 × 2.5mm, the number of theoretical plates is 47, the number of feed plates is 27, the reflux ratio is 4, the pressure at the top of the tower is 1 atm, the pressure at the bottom of the tower is 1.32 atm, and the temperature at the top of the tower is 1 atm. 99.7°C, the temperature of the tower kettle is 126.2°C;

See Table 4 for the composition of liquefied gas and ester products after esterification.

Table 4 Composition of model gas 2, liquefied gas and ester products after esterification

composition Conversion rate,% model gas 1 LPG after esterification Esters Propane, v% - 22.0 33.0 - Propylene, v% 70.1 15.0 6.9 - Butane, v% - 16.0 24.6 - Butene, v% 62.5 30.0 17.3 - Pentane, v% - 17.0 20.0 - Isopropyl acetate, v% - - - 35.9 sec-butyl acetate, v% - - - 64.1 Research Octane Number (RON) 121.3

It can be seen from Table 4 that the conversion rates of propylene and butene in the liquefied gas are 70.1% and 62.5% respectively. While reducing the olefin content in the liquefied gas, an ester mixture with a high octane number is produced. The research method The octane number is as high as 121.3, which can be used in gasoline blending components.

Claims (10)

1. a kind of method of liquefied gas esterification production high-knock rating gasoline blend component, this method comprises the following steps：

Liquefied gas is mixed by a certain percentage with organic acid, heated rear esterification of the feeding equipped with esterification catalyst Device, makes alkene and organic acid in liquefied gas that esterification occur in the presence of esterification catalyst；

Then esterification products feeding distillation system is separated, obtains high-quality liquefied gas and the Gaoxin of low olefin-content The esters of alkane value.

2. according to the method described in claim 1, wherein, the liquefied gas be upstream thermal cracking, coking and catalysis The liquefied gas that one or more in cracking unit are directly produced, the olefin(e) centent of the liquefied gas is 10-95wt%.

3. according to the method described in claim 1, wherein, the organic acid include with following general structure change One or more of combinations in compound：

In formula, R is H, CH₃、C₂H₅、C₃H₇In any one.

4. according to the method described in claim 1, wherein, the addition of the organic acid makes the liquefied gas and institute The volume ratio for stating alkene and organic acid in the mixed liquid phase stream of organic acid is 0.5-2:1.

5. according to the method described in claim 1, wherein, the esterification catalyst has high secondary ester selectivity, its Including metal oxide catalyst, zeolite molecular sieve catalyst, SO₄ ^2-/M_xO_yCatalyst and highly acidic cation are handed over The one or more of combinations changed in resin catalyst.

6. method according to claim 5, wherein, the metal oxide catalyst include with silica, At least one of molecular sieve and diatomite are carrier loaded ZnO, SnO and Al₂O₃At least one of metal oxidation Catalyst made by thing；Preferably, the carrier has meso-hole structure；

The zeolite molecular sieve catalyst include aluminium phosphate molecular sieve, aluminium silicophosphate molecular sieve, H types modenite, The molecular sieve catalyst that one or more in HY zeolites, H- β zeolites and HZSM-5 zeolites are mixed；It is excellent Selection of land, the zeolite molecular sieve catalyst is step hole zeolite molecular sieve catalyst；

The SO₄ ^2-/M_xO_yCatalyst is included SO₄ ^2-It is carried at least one of ZrO, ZnO and SnO metal Made SO on the carrier that oxide is made₄ ^2-/M_xO_yCatalyst；Preferably, the metal oxide is mesoporous Metal oxide；

The strong acid cation exchange resin catalyst includes Jie containing strong acid reaction group-large pore macromolecular and handed over Linked polymer catalyst.

7. according to the method described in claim 1, wherein, the esterifier be fixed bed esterifier.

8. according to the method described in claim 1, wherein, the condition of the esterification is：80-200 DEG C of temperature, Pressure 1-60atm, the liquid volume air speed 0.5-10h in terms of organic acid^-1。

9. according to the method described in claim 1, wherein, the distillation system include two or more rectifying Tower.

10. the method according to claim 1 or 9, wherein, when carrying out rectifying in the distillation system, first The high-quality liquefied gas of low olefin-content is separated using first rectifying column, and the tower top pressure control of the rectifying column System is in 1-10atm, and tower top temperature control is at 20-70 DEG C, and tower reactor Stress control is in 1-10atm, bottom temperature control At 100-200 DEG C, reflux ratio is controlled in 0.1-10；Second distillation column is recycled to enter the mixture of esters and organic acid The further rectifying of row, and in the distillation process using water as entrainer, the mixture of esters and organic acid and be total to The mol ratio for boiling agent water is 1-5:1, the tower top pressure control of the rectifying column is in 1-10atm, and tower top temperature control exists 50-90 DEG C, tower reactor Stress control is in 1-10atm, and bottom temperature control is at 90-150 DEG C, and reflux ratio is controlled in 0.1-5； Then split-phase is carried out to obtained esters and the mixture of a small amount of water, and then obtains high-octane esters；Utilize simultaneously Third distillation column carries out further rectifying, the tower top pressure of the rectifying column to obtained organic acid and the mixture of water Control is controlled at 80-120 DEG C in 1-10atm, tower top temperature, and tower reactor Stress control is in 1-10atm, bottom temperature Control is at 100-150 DEG C, and reflux ratio is controlled in 0.1-5, and obtained organic acid makes as the feedstock circulation of esterification With the water that obtained water is obtained with split-phase is recycled together as entrainer.