CN115672255B

CN115672255B - Thiol remover and aviation kerosene deodorization method

Info

Publication number: CN115672255B
Application number: CN202110873098.1A
Authority: CN
Inventors: 晋超; 翟维明; 刘锋; 褚阳
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2021-07-30
Filing date: 2021-07-30
Publication date: 2024-05-17
Anticipated expiration: 2041-07-30
Also published as: CN115672255A

Abstract

The invention discloses a mercaptan removal agent which comprises a carrier and an active component, wherein the carrier is a manganese oxide molecular sieve, and the active component is copper, and is characterized in that copper elements existing in a Cu ₂ O form in the active component account for not less than 20% of the total copper elements. The mercaptan removal agent provided by the invention realizes the purification of mercaptan by utilizing the special crystal structure of the active phase through the adsorption and catalytic conversion mode, has the advantages of low cost, high desulfurization precision, high sulfur capacity and high single-pass conversion rate, and has a good mercaptan removal effect. The mercaptan removal agent can directly remove mercaptan in aviation kerosene at a lower temperature, achieves the purpose of deodorization, has a simple process and convenient operation, and has good popularization prospect.

Description

Thiol remover and aviation kerosene deodorization method

Technical Field

The invention relates to the field of adsorbents, in particular to a mercaptan removal agent and application of the adsorbent in deodorizing aviation kerosene.

Background

Aviation kerosene (also called jet fuel, hereinafter referred to as aviation kerosene) is one of the most important products with the most important control indexes and the most strict quality requirements in petroleum products. There are two main methods for producing aviation kerosene: firstly, the heavy distillate oil is prepared by high-medium pressure hydrocracking, and secondly, the heavy distillate oil is refined by straight-run aviation kerosene, wherein the yield of the heavy distillate oil is maximum. The specific gravity, freezing point, smoke point and sulfur content of the straight-run aviation kerosene fraction of the main crude oil at home and abroad basically meet the requirements of aviation kerosene product indexes, but the thiol sulfur is generally higher, the thiol can cause the aviation kerosene to generate malodor, so that unstable substances in the aviation kerosene are easy to oxidize and fold to generate colloidal substances and sediments, the stability is influenced, precise parts of an engine are corroded, and the sensibility of the aviation kerosene to additives (such as antioxidants, metal deactivators and the like) is influenced. In order to reduce the sulfur content of mercaptan in aviation kerosene to no more than 20 mug/g, the refining process mainly comprises two types of hydrogenation technology and non-hydrogenation technology. In general, a non-noble metal hydrofining catalyst is adopted in the hydrofining process, but the reaction pressure, the reaction temperature and the hydrogen oil are relatively high, so that the investment and the operation cost are relatively high; or the noble metal catalyst is used, the severity of the operation condition can be reduced, but the noble metal catalyst has high cost and is easy to supplement sulfide poisoning, and the operation period is influenced. Therefore, the selective adsorption desulfurization technology is adopted to remove the mercaptan prospect in the aviation kerosene, which has important significance for supporting the development of national aviation industry and improving the aviation kerosene production scale and economic benefit of enterprises. The development of the mercaptan removal agent with high mercaptan capacity, low cost and simple operation has very practical significance.

Disclosure of Invention

The invention aims to provide a mercaptan removal agent and a aviation kerosene deodorization method, and in order to achieve the purposes, the invention specifically comprises the following two aspects:

The invention provides a mercaptan removal agent, which comprises a carrier and an active component, wherein the carrier is a manganese oxide molecular sieve, and the active component is copper, and is characterized in that copper elements in the form of Cu ₂ O in the active component account for not less than 20% of the total copper elements.

The invention also provides a aviation kerosene deodorization method, which comprises the steps of contacting the mercaptan removal agent and aviation kerosene raw materials containing mercaptan in a closed reactor isolated from oxygen, wherein the contact conditions comprise: the temperature is between room temperature and 100 ℃ and the time is between 0.1 and 12 hours. The room temperature refers to the environment temperature which does not need to be heated, and is generally 13-35 ℃, that is to say, the temperature range of the contact condition according to the invention can be 15-100 ℃ and 20-100 ℃ according to the different environment temperatures.

The active component in the mercaptan removal agent provided by the invention is copper, the content of Cu ₂ O is not lower than 20% of the total copper element, the mercaptan is purified by utilizing the special crystal structure of the active phase through the adsorption and catalytic conversion mode, the cost is low, the desulfurization precision is high, the sulfur capacity is high, the single-pass conversion rate is high, and the mercaptan removal agent has a good mercaptan removal effect. The mercaptan removal agent can directly remove mercaptan in aviation kerosene at a lower temperature, achieves the purpose of deodorization, has a simple process and convenient operation, and has good popularization prospect.

Detailed Description

The technical scheme of the invention is further described below according to specific embodiments. The scope of the invention is not limited to the following examples, which are given for illustrative purposes only and do not limit the invention in any way. Unless defined otherwise, all technical and scientific terms used herein have the meaning commonly understood by one of ordinary skill in the art. In case of conflict, the present specification, definitions, will control.

The invention provides a mercaptan removal agent which comprises a carrier and an active component, wherein the carrier is a manganese oxide molecular sieve, and the active component is copper, and is characterized in that copper elements existing in the form of Cu ₂ O in the active component account for not less than 20%, preferably not less than 30%, and more preferably 30-80% of the total copper elements.

The carrier in the mercaptan removal agent is manganese oxide molecular sieve, and the active component is copper. The manganese oxide molecular sieve can be one or more selected from birnessite, bucell ore, hydromanganese ore, barium manganese ore, potassium manganese ore and calcium manganese ore, and the active component copper part exists in the form of Cu ₂ O. Based on the dry weight of the mercaptan removal agent, the content of each component in the mercaptan removal agent in the invention is preferably: the content of the carrier is 80 to 99.5 wt%, and the content of the copper active component in terms of CuO is 0.5 to 20 wt%.

The specific surface area and pore volume of the thiol removal agent of the present invention are not particularly limited, and generally, the specific surface area may be 50 to 300m ²/g, and the pore volume may be 0.2 to 1.2cm ³/g.

The thiol remover used in the invention is not particularly limited in source, and can be a commercial reagent or prepared by the raw materials by themselves, so long as the composition, the content and the related parameters meet the corresponding requirements of the invention. In order to better realize the method, the invention provides two preparation methods for obtaining the mercaptan removal agent, namely a doping method and a loading method, which are respectively described as follows:

The method a is a doping method, which is to mix a reduced manganese compound with a copper metal salt and then mix the mixture with an oxidized manganese compound for hydrothermal reaction so as to prevent the copper metal salt and the oxidized manganese compound from forming an unexpected complex and changing a crystal structure, and mainly comprises the following steps:

(a-1) dissolving a reduced manganese compound and a copper metal salt in water to obtain a mixed solution;

(a-2) mixing an oxidized manganese compound with the mixed solution of the step (a-1), performing a hydrothermal reaction, and collecting a precipitate;

(a-3) drying, calcining and activating the precipitate of step (a-2) to obtain the thiol removal agent.

The manganese compounds in the oxidized state and the manganese compounds in the reduced state of the present invention are relatively speaking; the manganese compound in an oxidized state generally refers to a compound containing manganese in a relatively high valence state (e.g., mn ⁷⁺、Mn⁶⁺, etc.), and the manganese compound in a reduced state generally refers to a compound containing manganese in a relatively low valence state (e.g., mn ²⁺, etc.). For example, the oxidation state manganese compound is selected from one or more of potassium permanganate, potassium manganate and sodium permanganate, the copper metal salt is selected from one or more of copper nitrate, copper sulfide and copper chloride, and the reduction state manganese compound is selected from one or more of manganese sulfate, manganese nitrate, manganese acetate and manganese chloride; preferably, the molar ratio of the oxidized manganese compound, the reduced manganese compound, and the copper metal salt is (0.2 to 3): 1: (0.01-1).

Washing the precipitate obtained in step (a-2) with deionized water until the washing liquid is neutral (e.g., pH 6.5-7.5).

The drying and firing in the step (a-3) are conventional in the art, and the relevant conditions are not particularly limited, for example, the drying temperature in the step (a-3) is 80 to 350 ℃, preferably 100 to 300 ℃, for 1 to 24 hours, preferably 2 to 12 hours; the roasting temperature is 200-900 ℃, preferably 250-800 ℃ and the time is 0.5-12 h, preferably 2-6 h. The calcination may be carried out in an air atmosphere or in an inert gas atmosphere, preferably in an N ₂ atmosphere.

In order to further improve the performance of the mercaptan removal agent, the method further comprises the step of adding acid into the mixed solution between the step (a-2) and the step (a-2), and adjusting the pH value of the mixed solution to 0.2-3; the acid may be a common inorganic acid such as nitric acid, hydrochloric acid, sulfuric acid, or an organic acid such as acetic acid which can achieve the above object.

The method b is a loading method, firstly preparing a manganese oxide molecular sieve from an oxidized manganese compound and a reduced manganese compound, and then loading copper metal salt on the manganese oxide molecular sieve, and specifically comprises the following steps:

(b-1) subjecting an aqueous solution containing an oxidized manganese compound and a reduced manganese compound to a hydrothermal reaction, collecting a solid product, and performing first drying and first calcination to obtain a manganese oxide molecular sieve;

(b-2) supporting copper metal salt on the manganese oxide molecular sieve, and performing secondary drying and secondary roasting, and then activating to obtain the mercaptan removal agent.

Wherein the selection and content of the manganese compound in an oxidized state, the manganese compound in a reduced state and the copper metal salt can be referred to the method a, and preferably the method comprises the step of adding an acid to an aqueous solution before the hydrothermal reaction, adjusting the pH value of the aqueous solution to 0.2 to 3, and the selection of the kind of the acid can also be referred to the method a.

The hydrothermal reaction in method b is carried out under the conditions conventional in the art, the temperature is generally controlled to be 80-200 ℃, and in method a, the hydrothermal reaction temperature can be adjusted to be 150-200 ℃, so that the manganese oxide molecular sieve crystal structure is formed and copper-manganese ore (CuMn ₂O₄) is also formed.

The purpose of the activation in step (a-3) and step (b-2) is to convert copper in which the CuO form is present partially or totally into the Cu ₂ O form, preferably the activation conditions include: the activation atmosphere is a reducing atmosphere in which the reducing gas is hydrogen and/or carbon monoxide and the balance is nitrogen and/or an inert gas, the volume content of the reducing gas is 1-50%, more preferably 2-30%, the activation temperature is 50-200 ℃, more preferably 80-180 ℃, and the activation time is 0.5-5 hours, more preferably 0.8-3 hours.

The invention also provides a method for deodorizing aviation kerosene, which comprises the steps of contacting the mercaptan removal agent disclosed by the invention with an aviation kerosene raw material containing mercaptan in a reactor isolated from oxygen, wherein the contact conditions comprise: the temperature is between room temperature and 100 ℃ and the time is between 0.1 and 12 hours.

The source, the type and the content of the mercaptan-containing aviation kerosene raw material are not particularly limited, and any aviation kerosene which needs to be deodorized can be treated by the mercaptan removal agent disclosed by the invention, so that the purpose of deodorization is achieved. For example, aviation kerosene produced by hydrocracking a heavy distillate oil at high and medium pressures, aviation kerosene produced by refining a straight run aviation kerosene fraction, and the like.

According to the method, the deodorization of the aviation kerosene is carried out in a reactor isolated from oxygen, which can be a closed reactor protected by nitrogen and/or inert gas, or can be a continuous reaction under the atmosphere of nitrogen and/or inert gas. In the contact process, the contact efficiency can be increased by various conventional modes, and the deodorization effect is improved.

The method provided by the invention can directly obtain aviation kerosene with ultralow mercaptan content at a lower temperature, and the mercaptan removal agent has the advantages of low cost, high mercaptan removal precision, high sulfur capacity, high single pass conversion rate, convenient deodorization process, simple operation and contribution to industrialized popularization.

The present invention is further illustrated by the following specific examples, which are intended to be illustrative of the preferred embodiments and not limiting of the invention, and any equivalent examples of equivalent variations are possible by those skilled in the art using the teachings set forth above.

Reagents, instruments and tests

Unless otherwise specified, all reagents used in the present invention are analytically pure and commercially available.

The model of the XRD diffractometer adopted by the invention is XRD-6000 type X-ray powder diffractometer (Shimadzu), and XRD testing conditions are as follows: cu target, ka radiation (wavelength λ=0.154 nm), tube voltage 40kV, tube current 200mA, scan speed 10 ° (2θ)/min.

The content of the active ingredient was measured by X-ray fluorescence spectrometry RIPP-90 (petrochemical analysis method (RIPP experimental method), edited by Yang Cuiding, gu Kanying, wu Wenhui, first edition of science Press 1990, 9 th edition, pages 371-379).

The H ₂ S analyzer used in the invention is a German SICK GMS810 hydrogen sulfide analyzer.

Example 1

3.17G of potassium permanganate is dissolved in 40.55g of deionized water, the solution is heated and stirred to be dissolved to form potassium permanganate solution, 5.78g of 50 wt% manganese sulfate solution and 1.22g of copper nitrate are mixed and stirred uniformly, 6ml of nitric acid is added and stirred uniformly, the pH value is regulated to be less than 3, and the mixture is reacted for 24 hours at 130 ℃. The resulting brown precipitate was filtered and washed with deionized water several times until ph=7 of the washing solution, and then the solid product was dried at 120 ℃ overnight and calcined at 400 ℃ for 4 hours, and then treated at 120 ℃ for 1 hour with heating up to 120 ℃ in 10% h ₂ -Ar atmosphere to prepare a thiol removal agent A1:3% CuO-OMS-2, wherein the copper element in the form of Cu ₂ O accounts for 58% of the total copper elements.

Example 2

The thiol removal agent A2 was prepared in the same manner as in example 1, except that the content of CuO as the active component was varied, and the composition of A2 was 6% CuO-OMS-2, wherein the copper element present in the form of Cu ₂ O was 48% of the total copper element.

Example 3

Thiol removal agent A3 was prepared in the same manner as in example 1, except that the hydrothermal reaction temperature was not uniform, and the hydrothermal reaction was performed at 190℃to obtain thiol removal agent A3:3% CuO-OMS-2-190, wherein the copper element in the form of Cu ₂ O is 37% of the total copper element.

Example 4

The potassium permanganate solution, the manganese sulfate solution, copper nitrate and nitric acid were mixed and transferred to a flask equipped with a condenser tube, and refluxed at 120 ℃ for 24 hours, and the other steps were the same as in example 1, to obtain a thiol removal agent A4:3% CuO-OMS-2-Ref, wherein the copper element in the form of Cu ₂ O accounts for 40% of the total copper elements.

Example 5

Firstly, preparing a manganese molecular sieve OMS-2 carrier by a hydrothermal synthesis method, dissolving 3.17g of potassium permanganate in 40.55g of deionized water, heating and stirring to dissolve the potassium permanganate to form a potassium permanganate solution, then mixing the potassium permanganate solution with 5.78g of 50 wt% manganese sulfate solution, adding 6ml of nitric acid to adjust the pH value of the solution to 1.0, stirring uniformly, and reacting at 130 ℃ for 24 hours. The resulting brown precipitate was filtered and washed with deionized water several times until ph=7 of the washing solution, and then the solid product was dried overnight at 120 ℃, followed by calcination for 4 hours under an air atmosphere at 400 ℃ to prepare manganese oxide molecular sieve OMS-2.

Then copper nitrate is loaded on an OMS-2 carrier by a loading method, the solid product is dried overnight at 120 ℃ and roasted for 4 hours in air at 500 ℃, and then the thiol remover A6 is prepared by activating the solid product by the activating method in the example 1: 15% CuO-OMS-2, wherein the copper element in the form of Cu ₂ O represents 29% of the total copper element.

Comparative example 1

The mercaptan removal agent is selected from commercial zinc oxide desulphurisation agents (hereinafter referred to as D1).

XRD analysis of the thiol remover obtained in the example only shows characteristic peaks of OMS-2, which shows that the thiol remover has an OMS-2 molecular sieve structure and the active component copper is uniformly doped. The substitution of the doping method with the loading method does not affect the crystalline nature of the thiol removal agent.

Example 6

Transferring 0.5g of the mercaptan removal agent A1 of the embodiment 1 into a 50g reaction kettle of industrial aviation kerosene distillate containing mercaptan under the condition of isolating oxygen, filling nitrogen into the reaction kettle, stirring and reacting for 1h at 50 ℃ and normal pressure, filtering and removing the mercaptan removal agent after cooling to room temperature, and sending an oil sample to analyze mercaptan content, wherein the result is shown in the table 1.

Examples 7 to 10

The aviation kerosene fraction was treated in the same manner as in test example 6, except that the thiol removal agents were A2 to A5, respectively, and the results are shown in Table 1.

Example 8

The aviation kerosene fraction was treated in the same manner as in example 6, except that thiol removal agent A3 was selected to conduct the desulfurization reaction of the aviation kerosene fraction, and the results are shown in Table 1.

Comparative example 2

The results of the sweetening reaction of comparative example D1 and the aviation kerosene fraction were selected in the same manner as in example 6 and are shown in Table 1.

TABLE 1

* "Cu ₂ O ratio" means the percentage of copper element present in the form of Cu ₂ O in the mercaptan removal agent to total copper element.

According to the physicochemical properties of the manganese molecular sieve, the special crystal structure of the copper-based manganese molecular sieve is fully utilized, the advantages of the copper-based manganese molecular sieve in the field of mercaptan removal are fully exerted, and the copper-based manganese molecular sieve can have high mercaptan removal performance at a lower temperature. As can be seen from Table 1, in the thiol removal agent provided by the invention, after the copper-based molecular sieve adsorbent is subjected to activation treatment, the percentage of copper elements existing in the form of Cu ₂ O in the active component is higher than 20% of the total copper elements, and copper-manganese ore crystals formed in the thiol removal agent structure can further improve the desulfurization precision, so that the thiol removal performance is greatly improved. In addition, the specific surface area and the pore volume of the mercaptan removal agent are obviously larger than those of the zinc oxide of the comparative example, so that the pore volume and the specific surface area of the mercaptan removal agent are increased, mercaptan molecules can enter the pore canal of the mercaptan removal agent, and the mercaptan molecules are promoted to be adsorbed with the mercaptan removal agent. Therefore, the mercaptan removal agent provided by the invention has obviously higher desulfurization precision when being used for the mercaptan removal reaction including aviation kerosene deodorization than the prior art including commercial zinc oxide desulfurization agents. The mercaptan removal agent disclosed by the invention is simple in preparation mode, good in repeatability and beneficial to industrial popularization.

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the scope of the technical concept of the present invention, and all the simple modifications belong to the protection scope of the present invention.

Claims

1. The mercaptan removal agent comprises a carrier and an active component, wherein the carrier is a manganese oxide molecular sieve, and the active component is copper, and is characterized in that the content of the carrier is 80-99.5 wt% based on the dry weight of the mercaptan removal agent, and the content of the active component is 0.5-20 wt% based on CuO; the copper element in the form of Cu ₂ O in the active component accounts for not less than 20% of the total copper element.

2. The thiol removal agent of claim 1, wherein the manganese oxide molecular sieve is selected from one or more of birnessite, bucell ore, hydromanganese ore, barium manganese ore, potassium manganese ore, and calcium manganese ore.

3. The thiol removal agent according to claim 1, wherein the copper element present in the form of Cu ₂ O in the active component is present in a proportion of not less than 30% of the total copper element.

4. The thiol removal agent of claim 1, wherein the thiol removal agent is prepared by process a or process b;

The method a comprises the following steps:

(a-3) drying, roasting and activating the precipitate of step (a-2) to obtain the mercaptan removal agent;

The method b comprises the following steps:

5. The mercaptan removal agent according to claim 4, characterized in that in method a and method b, the manganese compounds in oxidation state are each independently selected from one or more of potassium permanganate, potassium manganate, sodium permanganate, the copper metal salts are selected from one or more of copper nitrate, copper sulphide, copper chloride, and the manganese compounds in reduction state are each independently selected from one or more of manganese sulphate, manganese nitrate, manganese acetate, manganese chloride.

6. The thiol removal agent according to claim 5, wherein the molar ratio of the oxidized manganese compound, the reduced manganese compound, and the copper metal salt is (0.2 to 3): 1: (0.01-1).

7. The mercaptan removal agent according to claim 4, characterized in that the drying temperature in step (a-3) of method a is 80-350 ℃, the time is 1-24 hours, the calcination temperature is 200-900 ℃ and the time is 0.5-12 hours; in the method b, the temperature of the first drying is 80-350 ℃, the time is 1-24 h, the temperature of the first roasting is 200-900 ℃, the time is 0.5-12 h, the temperature of the second drying is 80-350 ℃, the time is 1-24 h, and the temperature of the second roasting is 200-900 ℃ and the time is 0.5-12 h.

8. The thiol removal agent as claimed in claim 4, further comprising a step of adding an acid to the mixed solution between the steps (a-2) and (a-2), wherein the pH of the mixed solution is adjusted to 0.2 to 3.

9. The thiol removal agent as claimed in claim 4, further comprising a step of adding an acid to the aqueous solution before the hydrothermal reaction of the method b, wherein the pH of the aqueous solution is adjusted to 0.2 to 3.

10. The thiol removal agent of claim 4, wherein the activation conditions in process a and/or process b comprise: the activating atmosphere is a reducing gas atmosphere, wherein the reducing gas is H ₂ and/or CO, the volume content of the reducing gas is 1-50%, the activating temperature is 50-200 ℃, and the activating time is 0.5-5 hours.

11. The thiol removal agent as claimed in claim 10, wherein the volume content of the reducing gas is 2 to 30%, the activation temperature is 80 to 180 ℃, and the activation time is 0.8 to 3 hours.

12. A process for deodorizing aviation kerosene comprising contacting a thiol removal agent with a thiol-containing aviation kerosene feedstock in an oxygen-sequestering reactor, the contacting conditions comprising: the temperature is between room temperature and 100 ℃ and the time is between 0.1 and 12 hours; the mercaptan removal agent according to any one of claims 1-11, characterized in that the mercaptan removal agent is one of the mercaptan removal agents.

13. The method of claim 12, wherein the thiol-containing aviation kerosene feedstock has a thiol content of from 20 to 120ppm.