阅读说明：本技术 一种合成气直接制备高品质航油的方法 (Method for directly preparing high-quality aviation oil from synthesis gas ) 是由 吴晋沪 刘广波 李冰爽 王辉 李建青 訾仲岳 武景丽 于 2019-09-17 设计创作，主要内容包括：本发明公开了一种合成气直接制备高品质航油的方法,使用包括一段反应装置和二段反应装置的两段式反应系统,将合成气制低碳烃催化剂和低碳烃齐聚催化剂分别装入一段反应装置和二段反应装置。将惰性气体通入两段式反应系统在常压下吹扫3～5h,使其升温至300～500℃。将氢气混合气通入一段反应装置,使合成气制低碳烃催化剂被还原预处理3～8h；然后充压至0.5～5MPa。将合成气通入一段反应装置反应后将一段产物进行气液分离,得到液态产物和低碳烃混合气；将低碳烃混合气增压和/或脱除CO<Sub>2</Sub>后作为原料气送入二段反应装置发生合成反应,获得高品质航油。本发明具有工艺简单、产品品质高等优点。(The invention discloses a method for directly preparing high-quality aviation fuel from synthesis gas, which comprises the steps of using a two-section reaction system comprising a first-section reaction device and a second-section reaction device, and respectively loading a catalyst for preparing low-carbon hydrocarbon from the synthesis gas and a catalyst for oligomerization of the low-carbon hydrocarbon into the first-section reaction device and the second-section reaction device. And introducing inert gas into the two-stage reaction system, and purging for 3-5 hours at normal pressure to raise the temperature to 300-500 ℃. Introducing the hydrogen mixed gas into a first-stage reaction device, and carrying out reduction pretreatment on the catalyst for preparing the low-carbon hydrocarbon from the synthesis gas for 3-8 hours; then pressurizing to 0.5-5 MPa. Introducing the synthesis gas into a first-stage reaction device for reaction, and then carrying out gas-liquid separation on a first-stage product to obtain a liquid product and a low-carbon hydrocarbon mixed gas; pressurizing and/or removing CO from low-carbon hydrocarbon mixed gas 2 And then the raw material gas is sent into a two-stage reaction device to carry out synthetic reaction, and the high-quality aviation fuel is obtained. The invention has the advantages of simple process, high product quality and the like.)

1. The method for directly preparing the high-quality aviation fuel from the synthesis gas is characterized by using a two-stage reaction system comprising a first-stage reaction device and a second-stage reaction device, wherein the first-stage reaction device is used for preparing low-carbon hydrocarbons from the synthesis gas, and the second-stage reaction device is used for preparing the high-quality aviation fuel from the low-carbon hydrocarbons through oligomerization; the method comprises the following steps:

respectively loading a low-carbon hydrocarbon catalyst prepared from 20-40 meshes of synthetic gas and a low-carbon hydrocarbon oligomerization catalyst into a first-stage reaction device and a second-stage reaction device;

introducing inert gas into a two-stage reaction system, and purging for 3-5 hours at normal pressure; heating the two-stage reaction system to 300-500 ℃ at a heating rate of 2-20 ℃/min;

introducing the hydrogen mixed gas into a first-stage reaction device, and carrying out reduction pretreatment on the catalyst for preparing the low-carbon hydrocarbon from the synthesis gas for 3-8 hours; further pressurizing the first-stage reaction device to 0.5-5 MPa;

introducing the synthesis gas into a first-stage reaction device, and reacting the synthesis gas under the action of a catalyst for preparing low-carbon hydrocarbon from the synthesis gas to generate a first-stage product containing the low-carbon hydrocarbon; carrying out gas-liquid separation on the first-stage product to obtain a low-carbon hydrocarbon mixed gas and part of high-carbon-number oil products;

pressurizing and/or removing CO from low-carbon hydrocarbon mixed gas₂Then the mixture is used as a raw material and sent into a two-stage reaction device, and a synthetic reaction is carried out under the action of a low-carbon hydrocarbon oligomerization catalyst to generate a high-carbon number oil product, so as to obtain the high-quality aviation oil.

2. The method for directly preparing high-quality aviation oil from synthesis gas according to claim 1, wherein the mass percent x of hydrogen in the hydrogen mixture is 0%<x<50 percent; the synthesis gas comprises H₂And CO, and H₂The ratio of/CO is 0.5 to 3.

3. The method for directly preparing high-quality aviation oil from synthesis gas according to claim 1, wherein the catalyst for preparing low-carbon hydrocarbon from synthesis gas is selected from metal, metal oxide or metal carbide, and the metal comprises any one or more of iron, cobalt, manganese and copper.

4. The method for directly preparing high-quality aviation oil from synthesis gas according to claim 1, wherein the low-carbon hydrocarbon oligomerization catalyst comprises a ZSM-5 molecular sieve and an acid component, and a modification component and/or a load, and the ZSM-5 molecular sieve has a mass percent x of 30%<x<100 percent; the acid component comprises phosphoric acid or sulfuric acid; the modified component is nickel salt and/or zinc salt; the load is Al₂O₃And/or SiO₂。

5. The method for directly preparing high-quality aviation oil from synthesis gas according to claim 1, wherein the first-stage reaction device is a fixed bed reactor or a slurry bed reactor, the reaction temperature for preparing low-carbon hydrocarbon from synthesis gas of the first-stage reaction device is 210-350 ℃, the pressure is 0.5-5 MPa, and the space velocity is 800-10000 h^-1。

6. The method for directly preparing high-quality aviation oil from synthesis gas according to claim 1, wherein the second-stage reaction device is a fixed bed reactor, a fluidized bed reactor or a slurry bed reactor, and the reaction temperature for preparing high-quality aviation oil by oligomerization of low-carbon hydrocarbons in the second-stage reaction device is 180-350 ℃, the pressure is 0.5-6 MPa, and the space velocity is 800-10000 h^-1。

Technical Field

The invention relates to a method for directly preparing high-quality aviation oil from synthesis gas, belonging to the technical field of aviation oil preparation.

Background

The aviation industry is the only traffic field completely depending on liquid fuel, and the development of the technology for preparing aviation kerosene by using synthetic gas is a great strategic demand for sustainable development of energy in China. With the development of the Chinese economic society, the number of newly built airports and airplane frames is continuously increased, and the consumption of the Chinese aviation kerosene is in a continuous increasing situation. Aviation fuel is a strategic material of a country as a liquid fuel with a great international demand at present. At present, the China aviation fuel mainly takes petroleum as a raw material, the yield of the China aviation fuel in a crude oil refined product is less than 10%, and the external dependence of the China petroleum is close to 70%. The Chinese energy shows the structural characteristics of rich coal, lean oil and little gas, and the synthetic gas can be obtained from various ways such as coal, biomass and the like as an important platform for energy conversion, and has important significance for Chinese energy safety and environmental protection by directly converting the synthetic gas into aviation fuel.

The aviation fuel oil generally consists of hydrocarbons with the carbon number of 6-16, and comprises a plurality of components such as alkane, cyclane and aromatic hydrocarbon (Prem L, Donald H, Philip D. environmental Science & Technology,2011,45, 10744-.

At present, the aviation fuel oil prepared by converting synthesis gas is prepared by a multi-Fischer-Tropsch synthesis route, the reaction comprises a fixed bed, a slurry bed, a moving bed and other processes, but the Fischer-Tropsch process has the characteristics of wide carbon number distribution of products (according with ASF distribution), most of products are straight-chain hydrocarbons and the like essentially, so that the selectivity of the oil prepared by the Fischer-Tropsch process is low, the product has a simple structure/cannot directly meet the requirements of aviation fuel components, and the product needs to be further refined and blended to be used as aviation fuel (H.Galvis, K.Jong, ACS catalysis.2013,3,2130, 2149; ASTM-D7566-18, 2018).

Disclosure of Invention

The invention aims to provide a method for directly preparing high-quality aviation oil from synthesis gas, which is characterized in that the synthesis gas is directly prepared into C2-C5 low-carbon hydrocarbons under the action of a catalyst, then the C2-C5 low-carbon hydrocarbons are further subjected to trimerization and tetramerization under the action of an acid catalyst to controllably generate a longer carbon chain product (C6-C16), and the oligomerization is accompanied by isomerization, cyclization, aromatization and other reactions to prepare the aviation fuel with controllable carbon number and rich product molecular composition structure.

The invention is realized by the following technical scheme:

a method for directly preparing high-quality aviation fuel from synthesis gas uses a two-stage reaction system comprising a first-stage reaction device and a second-stage reaction device, wherein the first-stage reaction device is used for preparing low-carbon hydrocarbons from the synthesis gas, and the second-stage reaction device is used for preparing high-quality aviation fuel from the low-carbon hydrocarbons by oligomerization; the method comprises the following steps:

respectively loading a low-carbon hydrocarbon catalyst prepared from synthesis gas and a low-carbon hydrocarbon oligomerization catalyst into a first-stage reaction device and a second-stage reaction device;

introducing inert gas into a two-stage reaction system, and purging for 3-5 hours at normal pressure; heating the two-stage reaction system to 300-500 ℃ at a heating rate of 2-20 ℃/min;

introducing the hydrogen mixed gas into a first-stage reaction device, and carrying out reduction pretreatment on the catalyst for preparing the low-carbon hydrocarbon from the synthesis gas for 3-8 hours; then further pressurizing the first-stage reaction device to 0.5-5 MPa;

introducing the synthesis gas into a first-stage reaction device, and reacting the synthesis gas under the action of a catalyst for preparing low-carbon hydrocarbon from the synthesis gas to generate a first-stage product containing the low-carbon hydrocarbon; carrying out gas-liquid separation on the first-stage product to obtain a liquid product serving as an oil product and a low-carbon hydrocarbon mixed gas serving as a second-stage reaction raw material;

pressurizing and/or removing CO from low-carbon hydrocarbon mixed gas₂Then the mixture is sent into a two-stage reaction device as a raw material, and is subjected to synthetic reaction under the action of a low-carbon hydrocarbon oligomerization catalyst to generate a C6-C16 hydrocarbon mixture containing alkane, cycloalkane and arene, namely an oil product, so as to obtain the high-quality aviation oil.

In the technical scheme, the mass percent x of the hydrogen contained in the hydrogen mixture is 0 percent<x<50 percent; the synthesis gas comprises H₂And CO, and H₂The ratio of/CO is 0.5 to 3.

In the above technical scheme, the catalyst for preparing low carbon hydrocarbon from synthesis gas is selected from metal, metal oxide or metal carbide, and the metal comprises any one or a mixture of iron, cobalt, manganese and copper.

The technical proposal is thatThe low-carbon hydrocarbon oligomerization catalyst comprises a ZSM-5 molecular sieve, an acid component, a modified component and/or a load, wherein the mass percent x of the ZSM-5 molecular sieve is 30%<x<100 percent; the acid component comprises phosphoric acid or sulfuric acid; the modified component is nickel salt and/or zinc salt; the load is Al₂O₃And/or SiO₂。

In the technical scheme, the first-stage reaction device adopts a fixed bed reactor or a slurry bed reactor, the reaction temperature for preparing the low-carbon hydrocarbon from the synthesis gas of the first-stage reaction device is 210-350 ℃, the pressure is 0.5-5 MPa, and the airspeed is 800-10000 h^-1。

In the technical scheme, the second-stage reaction device adopts a fixed bed reactor, a fluidized bed reactor or a slurry bed reactor, and the reaction temperature of the low-carbon hydrocarbon oligomerization high-quality aviation oil of the second-stage reaction device is 180-350 ℃, the pressure is 0.5-6 MPa, and the airspeed is 800-10000 h^-1。

The invention has the advantages that: the preparation method of the catalyst is simple; the catalyst is used in the process of preparing high-quality aviation fuel components by oligomerizing low-carbon hydrocarbons, has wide raw material application range, directly obtains products containing all components of aviation fuel such as aromatic hydrocarbon, naphthenic hydrocarbon, isomeric hydrocarbon and the like, and has simple process and high product quality.

Detailed Description

The following further describes the embodiments and operation of the present invention.

The invention adopts a two-section reaction system comprising a first-section reaction device and a second-section reaction device, wherein the first-section reaction device is used for preparing low-carbon hydrocarbon from synthesis gas, and the second-section reaction device is used for preparing high-quality aviation oil from the low-carbon hydrocarbon through oligomerization. The first-stage reaction device is a fixed bed reactor or a slurry bed reactor, and the second-stage reaction device is a fixed bed reactor, a fluidized bed reactor or a slurry bed reactor. The reaction temperature for preparing the low-carbon hydrocarbon from the synthesis gas of the first-stage reaction device is 210-350 ℃, the pressure is 0.5-5 MPa, and the space velocity is 800-10000 h^-1. The reaction conditions for oligomerization of the low-carbon hydrocarbon of the second-stage reaction device to prepare the high-quality aviation fuel can be consistent with the conditions of the first-stage reaction device, and can also be selected from the following steps: the reaction temperature is 180-350 ℃ and the pressure0.5-6 MPa and airspeed of 800-10000 h^-1。

The process and effect of producing high quality aviation fuel from synthesis gas by the process of the present invention is further illustrated by the following examples. Wherein, the selectivity of the aviation oil refers to the proportion of the hydrocarbon components of C6-C16 in the total product