CN110016362B - Method for preparing alkylate oil by taking metal compound as auxiliary agent - Google Patents

Abstract

The invention belongs to the field of petrochemical industry, and in particular relates to a method for preparing an alkylated oil by using a metal compound as an auxiliary agent. The alkylation reaction is carried out by using isobutane and carbon tetraolefin as raw materials, and the catalyst is a strong protic acid such as concentrated sulfuric acid. The auxiliary agent is a metal compound of lanthanum or bismuth, the addition amount of the auxiliary agent is 0.5wt%-10wt%, the reaction temperature is in the temperature range of 20-80°C, the pressure is 0.1-2.0MPa, and the time is 0.1-60min. The metal compounds of lanthanum or bismuth can be used as alkylation assistants to generate high-quality and high-yield alkylate oil, which can control the acid strength of the catalyst, improve the selectivity of carbon eight components in the prepared alkylate oil, and reduce the The content of by-products, and the catalytic system can be recycled to reduce the acid consumption of the protic acid catalyst. When the reaction is complete, the catalytic system will separate from the alkylation product.

Description

A kind of method for preparing alkylate oil with metal compound as auxiliary agent

technical field

The invention belongs to the field of petrochemical industry, and particularly relates to a method for preparing alkylated oil by using a metal compound as an auxiliary agent.

Background technique

Under the two-wheel drive of strengthening environmental governance and accelerating the quality upgrade of refined oil, the demand for high-octane gasoline additives will greatly increase. The alkylation reaction of isobutane and olefins under the action of strong acid is an important process for producing clean gasoline components in the petrochemical field. Aromatics and other characteristics make it an ideal clean gasoline blending component.

The traditional alkylation catalysts are hydrofluoric acid and concentrated sulfuric acid. Hydrofluoric acid has strong corrosiveness, toxicity and volatility, and poses a great threat to people and the environment. It has been banned and prohibited from building hydrogen in some areas. Fluoric acid device. The concentrated sulfuric acid alkylation process occupies a large proportion in the Chinese market. Although the process is relatively mature, there are also problems such as large discharge of waste acid, high regeneration cost and environmental pollution. In recent decades, many researchers have improved and perfected the concentrated sulfuric acid process to reduce acid consumption and improve the quality of alkylation products, mainly divided into two aspects: strengthening acid-hydrocarbon mixing and adding additives. In terms of strengthening the mixing of acid and hydrocarbons, design and improve new reactors, such as the use of supergravity reactors, impingement flow reactors and other new reactors to improve the degree of liquid-liquid mixing and enhance heat exchange efficiency. In terms of adding additives, it is mainly divided into the following aspects: 1) Surfactant as an auxiliary can enhance the mixing degree of the acid-hydrocarbon interface, increase the solubility of isobutane, reduce side reactions, and improve alkylation. product quality. Such as dodecylbenzenesulfonic acid and p-phenylenediamine (US3655807, US3689590), N,N,N-trialkylphosphoric triamide (US3865896) and so on. 2) Buffer additive, by improving the acid-hydrocarbon interface, delaying the change of acidity and prolonging the life of the catalyst, etc. For example, Huang et al. (Ind.Eng.Chem.Res.2015,54,1464-1469) used 0.5wt% of [Bmim][SbF ₆ ] and 40ml of concentrated sulfuric acid as a catalyst, the acid-hydrocarbon ratio was 40/50, and the reaction time For 10 min, the obtained C8 content was 90.07%, the selectivity of TMPs was 82.03%, the octane number was 98, and the catalyst life was nearly doubled. Wang et al. (Ind.Eng.Chem.Res., 2016, 55(30):8271-8280) used [N ₂₂₂₄ ]NTf ₂ and trifluoromethanesulfonic acid to form an ionic buffer effect, which also improved the effect of trifluoromethanesulfonic acid Catalytic performance and lifetime. 3) Hydrogen transfer assistant, which enhances the rate of hydrogen transfer in the reaction control step, so that more alkylation products are transferred to C8 and TMPs (trimethylpentane). For example, amantadine and its ionic liquid.

Invention content:

The main purpose of the present invention is to provide a kind of auxiliary agent for improving the catalyzed alkylation of protonic acid, for improving the quality of alkylation products and reducing acid consumption, and the concrete technical scheme adopted is as follows:

The invention provides a method for preparing alkylate oil by using metal compounds as auxiliary agents, which means that under the condition of alkylation of isobutane and olefin, protic acid is used as catalyst, and metal compounds such as lanthanum and bismuth are used as auxiliary agents An alkylation reaction is carried out to obtain an alkylated oil.

In the method proposed by the present invention, the olefins are one or more mixtures of 1-butene, 2-butene, isobutene, and C4 after ether, and the molar ratio of isobutane and olefin is 1:1～ 180:1.

In the method proposed by the present invention, the catalyst is a protonic acid such as concentrated sulfuric acid, trifluoromethanesulfonic acid, and hexafluoroisopropoxysulfonic acid, and the auxiliary agent is a metal compound of lanthanum or bismuth, such as lanthanum trifluoromethanesulfonate and Triphenyl bismuth, etc., the catalyst and the promoter synergistically catalyze the preparation of alkylate oil.

In the method proposed by the present invention, the addition amount of the auxiliary agent is 0.5wt% to 10wt%.

In the method proposed by the present invention, the volume ratio of the catalyst to the mixed feedstock hydrocarbon can be adjusted within 0.01-2 to obtain high-quality alkylate oil.

In the method proposed by the present invention, the alkylation reaction is carried out in the temperature range of -20～80℃, the reaction pressure is 0.1～2.0MPa, and the reaction time is 0.1～60min.

In the method proposed by the present invention, the alkylation reaction takes place in a stirred reactor, a packed bed reactor, a microfluidic reactor, a hypergravity reactor, an ultrasonic reactor, a liquid-liquid two-phase mixing reactor, etc. The reaction can also be produced continuously.

Compared with the existing concentrated sulfuric acid alkylation process, the present invention provides a method for preparing alkylated oil by using metal compounds as auxiliary agents, and has the following advantages: the metal compounds of lanthanum or bismuth are used as alkylation auxiliary agents, The acid strength of the catalyst can be regulated, the selectivity of the C8 component in the prepared alkylate oil can be improved, the content of by-products can be reduced, and the catalytic system can be recycled to reduce the acid consumption of the proton acid catalyst.

The present invention will be described in further detail below. However, the following examples are only simple examples of the present invention, and do not represent or limit the protection scope of the present invention. The protection scope of the present invention is subject to the claims.

Detailed ways:

In order to make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention are further described below through specific embodiments. In order to better illustrate the present invention and facilitate the understanding of the technical solutions of the present invention, typical but non-limiting examples of the present invention are as follows.

Comparative Example 1:

40ml of concentrated sulfuric acid was added to the stirred reaction kettle, and the air in the kettle was first replaced with nitrogen to maintain a certain pressure in the kettle, so that the mixed hydrocarbons remained liquid and participated in the reaction. Turn on the stirring and constant temperature tank, wait for the temperature in the kettle to reach 3 °C, use a double plunger micro pump to feed 50 ml of hydrocarbon mixed raw materials at a feed rate of 500 mL/h, and the ratio of alkene to olefin is 10:1. After 10 minutes of reaction, the stirring was stopped, the unreacted isobutane was collected in the air bag for detection, the liquid in the reaction kettle was poured out, and the layers were separated after standing. The upper layer was alkylated oil, and the lower layer was acid. The alkylated oil was saturated with Sodium bicarbonate solution and deionized water were washed three times, respectively, and sent to gas chromatography for oil analysis. Gas chromatography (SHIMADZU GC 2014) was used for oil analysis, and the FID detector was a DB-Petro 100m × 0.25mm × 0.50μm capillary chromatographic column. The normalization method was used for quantification. The composition of the obtained alkylated oil is shown in Table 1.

Example 1:

The operation steps are as in Comparative Example 1, the catalyst is 40ml of concentrated sulfuric acid, the auxiliary agent is 0.05g of lanthanum trifluorosulfonate, and other conditions remain unchanged, and the results are shown in Table 1.

Comparative Example 2:

Preparation of hexafluoroisopropoxysulfonic acid: slowly add equimolar hexafluoroisopropanol dropwise to chlorosulfonic acid at -20 °C, and keep stirring, and slowly increase to 140 °C until HCl gas is no longer released. The reaction mixture was distilled under reduced pressure to obtain hexafluoroisopropoxysulfonic acid. The operation steps of the alkylation process are as in Comparative Example 1, the catalyst is 10 ml of hexafluoroisopropoxysulfonic acid, and other conditions remain unchanged. The results are shown in Table 1.

Example 2:

The operation steps are as in Comparative Example 1, the catalyst is 10 ml of hexafluoroisopropoxysulfonic acid, the auxiliary agent is 0.02 g of lanthanum trifluoromethanesulfonate, other conditions remain unchanged, and the results are shown in Table 1.

Example 3:

The operation steps are as in Comparative Example 1, the catalyst is 10 ml of hexafluoroisopropoxysulfonic acid, the auxiliary agent is 0.04 g of lanthanum trifluoromethanesulfonate, and other conditions remain unchanged, and the results are shown in Table 1.

Example 4:

The operation steps are according to Comparative Example 1, the catalyst is 10 ml of hexafluoroisopropoxysulfonic acid, the auxiliary agent is 0.02 g of triphenylbismuth, and other conditions remain unchanged. The results are shown in Table 1.

Example 5:

The operation steps are according to Comparative Example 1, the catalyst is 10ml of hexafluoroisopropoxysulfonic acid, the auxiliary agent is 0.04g of triphenylbismuth, other conditions are unchanged, and the results are shown in Table 1.

Table 1 Alkylation effect of different examples

The applicant declares that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art can understand that the technical solutions of the present invention can be modified. Or equivalent replacements, without departing from the spirit and scope of the technical solutions of the present invention, should be included in the scope of the claims of the present invention.

The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the specific details of the above-mentioned embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention. These simple modifications All belong to the protection scope of the present invention.

In addition, it should be noted that the specific technical features described in the above-mentioned specific embodiments can be combined in any suitable manner unless they are inconsistent. In order to avoid unnecessary repetition, the present invention provides The combination method will not be specified otherwise.

In addition, the various embodiments of the present invention can also be combined arbitrarily, as long as they do not violate the spirit of the present invention, they should also be regarded as the contents disclosed in the present invention.

Claims (6)

1. a method for preparing alkylated oil with metal compound as auxiliary agent, is characterized in that, with isobutane and carbon tetraolefin as alkylation reaction raw material, with strongly acidic protonic acid as catalyzer, lanthanum or bismuth The metal compound is the auxiliary agent, and the three are contacted in the reactor. The catalyst and the auxiliary agent cooperate to catalyze the alkylation reaction to prepare alkylate oil. After the reaction is completed, stand and separate to obtain high-octane alkylate oil. , wherein the strongly acidic protonic acid is concentrated sulfuric acid, trifluoromethanesulfonic acid, hexafluoroisopropoxysulfonic acid, the metal compound of lanthanum or bismuth is lanthanum trifluoromethanesulfonate, triphenylbismuth, and the The addition amount of the auxiliary agent is 0.5wt%-10wt%. 2. method according to claim 1, is characterized in that, carbon tetraolefin is 1-butene, 2-butene, isobutene, ether after carbon four one or the mixture of two or more above-mentioned carbon four olefins, isobutylene A suitable molar ratio of alkane to alkene is from 1:1 to 180:1. 3 . The method according to claim 1 , wherein the volume ratio of the catalyst to the mixed raw materials of isobutane and carbon tetraolefin is adjusted within 0.01-2 to obtain better alkylate oil. 4 . 4 . The method according to claim 1 , wherein the alkylation reaction is carried out in the temperature range of -20 to 80° C., the reaction pressure is 0.1 to 2.0 MPa, and the reaction time is 0.1 to 60 min. 5 . 5. The method according to claim 1, wherein the alkylation reaction is carried out in a stirred reactor, a packed bed reactor, a microfluidic reactor, a hypergravity reactor, an ultrasonic reactor, or a liquid-liquid two-phase mixing Reactor, batch reaction or continuous production. 6. The method according to claim 1, characterized in that, after the alkylation reaction, the alkylate oil can be obtained by standing and separation, and the upper layer alkylate oil is taken out; the lower layer catalytic system is continuously put into the reaction, and the catalytic system can be recycled Use to reduce acid consumption.