阅读说明：本技术 一种轻油在非加氢或临氢气氛下脱硫的方法 (Method for desulfurizing light oil in non-hydrogenation or hydrogenation atmosphere ) 是由 宋华 于 2020-06-17 设计创作，主要内容包括：本发明公开了一种轻油在非加氢或临氢气氛下脱硫的方法,该方法在非加氢或临氢气氛下,将船用燃料油、催化柴油、直馏柴油、催化汽油等轻油脱硫转变为低硫含量的清洁燃料,从而大幅度提高轻油的经济价值。本发明利用甲烷、乙烷、丙烷或天然气气氛,利用多金属负载催化剂在较低温度和较低压力的条件下,通过活化轻油中的烃分子和甲烷分子,实现其C-S键的活化与断裂,在实现了较低焦炭产率、较高液体收率的同时降低了油品硫含量,解决了目前柴油等轻油加氢脱硫制备清洁油品过程中催化剂成本较高、工艺流程复杂、需要使用昂贵的高压氢气、固定资产投资较大、经济效益偏低等一系列问题。为低成本降低轻油S含量,生产清洁油品以及高效利用甲烷提供了一种新途径。(The invention discloses a method for desulfurizing light oil in a non-hydrogenation or hydrogenation atmosphere, which converts the light oil desulfurization of marine fuel oil, catalytic diesel oil, straight-run diesel oil, catalytic gasoline and the like into clean fuel with low sulfur content in the non-hydrogenation or hydrogenation atmosphere, thereby greatly improving the economic value of the light oil. The invention realizes the activation and the breakage of C-S bonds by activating hydrocarbon molecules and methane molecules in light oil by utilizing methane, ethane, propane or natural gas atmosphere and utilizing a multi-metal supported catalyst under the conditions of lower temperature and lower pressure, reduces the sulfur content of oil products while realizing lower coke yield and higher liquid yield, and solves a series of problems of higher catalyst cost, complex process flow, need of using expensive high-pressure hydrogen, larger investment of fixed assets, lower economic benefit and the like in the process of preparing clean oil products by hydrodesulfurization of light oil such as diesel oil and the like at present. Provides a new way for reducing the content of light oil S with low cost, producing clean oil products and efficiently utilizing methane.)

1. A method for desulfurizing light oil in non-hydrogenation or hydrogen atmosphere is characterized in that in the non-hydrogenation or hydrogen atmosphere, under the action of a catalyst, the method efficiently converts and removes sulfur-containing compounds in the light oil in a reactor, and reduces the sulfur content in the product oil.

2. The method for desulfurizing light oil in a non-hydrogenation or hydrogen atmosphere according to claim 1, wherein the light oil is one or a mixture of more of bunker fuel oil, catalytic diesel oil, straight-run diesel oil and catalytic gasoline.

3. The method for desulfurizing light oil in a non-hydrogenation or hydrogen atmosphere according to claim 1, wherein the catalyst is prepared by loading various metals on a formed carrier, the carrier material is preferably a silica-alumina molecular sieve comprising one of FAU, MFI and BEA molecular sieves, and the silica-alumina ratio ranges from 2.5:1 to 280: 1.

4. The method for desulfurizing light oil in a non-hydrogenation or hydrogen atmosphere according to claim 3, wherein the silica-alumina ratio of the MFI type molecular sieve is 20:1 to 30: 1.

5. A method for desulphurizing a light oil according to claim 3 in a non-hydrogenated or hydrogenated atmosphere, wherein the metals selected are two or more of Ga, Mo, Ag, Co, Ni and Ce, and the metal sources used are their corresponding soluble sourcesSalts of Ga (NO)₃)₃，(NH₄)₆Mo₇O₂₄，AgNO₃，Co(NO₃)₂，Ni(NO₃)₂And Ce (NO)₃)₃The metal loading, namely the weight ratio of the metal oxide to the carrier, is 1 to 20 weight percent, wherein the loading proportion is as follows: 1 wt% Ga, 1 wt% Ag and 10 wt% Mo.

6. A method for desulfurizing light oil according to claim 5 in a non-hydrogenation or hydrogen atmosphere, wherein the catalyst is prepared by: firstly, dissolving soluble metal salt in water to form a metal precursor solution, then soaking the metal precursor solution into a porous carrier, drying at the temperature of 80-120 ℃ for 1-2 h, roasting at the temperature of 500-700 ℃ for 2-5 h, and controlling the temperature rise rate from room temperature to the roasting temperature to be 5-20 ℃/min.

7. A method for desulphurizing a light oil in a non-hydrogenated or hydrogenated atmosphere according to claim 3, wherein the support material is in the form of a powder or a shaped support; wherein, the carrier in the form of powder is directly made of molecular sieve material, and the preparation method of the formed carrier comprises the following steps: according to the molecular sieve material: methyl cellulose: adhesive: the weight ratio of the acid solution is 1: 0.05-0.2: 0.1-0.5 to form a mixture, molding, drying at 80-120 ℃ for 2h, roasting at 500-700 ℃ for 2-5 h, and controlling the heating rate from room temperature to roasting temperature to be 5-20 ℃/min; the binder comprises one or more of silica sol, aluminum sol and acidified pseudo-boehmite, and the acid solution comprises one or more of acetic acid and citric acid aqueous solutions, and the concentration of the acid solution is 5-10%.

8. The method for desulfurizing light oil in a non-hydrogenation or hydrogen atmosphere according to claim 1, wherein the reactor is one or more of a batch autoclave reactor, a continuous fixed bed reactor and a semi-batch reactor; in a batch autoclave reactor, light oil and catalyst are addedThe mass ratio of the agent is 100:1 to 1: 10; in the continuous fixed bed reactor, the liquid hourly space velocity of the light oil is 0.1h^-1To 5h^-1The reaction temperature is 350-450 ℃, and the reaction pressure is 1-50 atmospheric pressures.

9. The method for converting light oil into aromatic hydrocarbon according to claim 1, wherein the reaction atmosphere is methane, ethane, propane or natural gas.

Technical Field

The invention belongs to the field of petroleum refining and petroleum processing, and particularly relates to a method for desulfurizing light oil in a non-hydrogenation or hydrogenation atmosphere_xExhaust of polluted gasesAnd (4) placing.

Background

In recent years, the total amount of heavy and poor crude oil processed and the proportion of the processed amount in all the raw oil have gradually increased. The poor crude oil generally has high content of heteroatoms such as S, N, so the fuel oil obtained by refining, particularly the diesel oil product, often has high sulfur content. The organic sulfur in diesel oil usually exists in the form of thioether, thiophene and benzothiophene, and SO can be generated after combustion_xThese SO_xNot only corrodes the combustion chamber and the exhaust emission system of the engine, but also can enter the interior of the diesel engine through the gap of the piston ring of the diesel engine so as to accelerate the deterioration of lubricating oil. Generally, the higher the S content in gas oils such as diesel oil, the more serious the problem becomes. In recent years, more and more environmental problems are gradually presented, and governments and international organizations of various countries have also developed a series of policy regulations to regulate the content of S in fuel oil. For example, the canadian government requires that the S content in diesel fuel used by transportation vehicles must be less than 15ppm from 2006, and that the S content in train locomotives and bunker fuel oil must also be less than 15ppm from 2012 onwards. Particularly recently, the international maritime organization also requires that ships driving in a general area from 1 month 2020 have to have a substantial reduction in the S content of fuel oil from 3.5% to less than 0.5%, i.e. 5000 ppm.

In recent years, along with the great oscillation of crude oil price and the gradual obvious trend of energy diversification, global refining enterprises present new situations of refining integration and transformation of oil refining to chemical engineering, and give consideration to high-yield high-quality clean fuel while producing high-yield chemical products, so that the process for producing traditional gasoline and diesel oil is gradually upgraded to produce low-sulfur or ultra-low-sulfur clean fuel. Therefore, there is a need for developing new processes and new technologies for the desulfurization of gasoline and diesel.

The most widely used diesel desulfurization technology at present is diesel hydrofining desulfurization. The technology is to convert organic sulfide in diesel oil into H under the action of catalyst in the presence of high-pressure hydrogen₂S and then desulfurization is carried out. The catalyst used in the reaction adopts chromium, molybdenum, tungsten, iron, cobalt, nickel, platinum and the like, and can also be used by combining cobalt-molybdenum, nickel-molybdenum or nickel-cobalt-molybdenum, and generallyAlumina is used as a carrier. In the diesel oil hydrofining production process, if carbon deposits on the surface of the catalyst and organic metal compounds of vanadium and nickel in heavy oil react with hydrogen and deposit on the catalyst, the catalyst is poisoned and loses the catalytic action. To solve this problem, two processes, direct desulfurization and indirect desulfurization, have been developed. The direct desulfurization is to select a catalyst with better poisoning resistance to directly carry out hydrodesulfurization, and simultaneously adopt proper protective measures, such as adding a protective tower in front of a reaction tower in the existing process, filling other cheap catalysts, and removing impurities and metal components as far as possible. The indirect desulfurization is to distill heavy oil under reduced pressure and separate the heavy oil into distillate oil and residual oil. The distillate oil is separately hydrodesulfurized and then mixed with the residual oil. Or treating the residual oil with liquefied propane (or butane) as solvent, separating out asphalt, and mixing with distillate oil for hydrogenation treatment. The reaction mechanism is that MoS is utilized₂Unsaturated coordination sites in the isodesulfurization active material phase are combined with S atoms in the diesel oil molecules to form Mo-S bonds, so that C-S chemical bonds are cut off, and active H is utilized₂Binding to the S site to form H₂S thereby restoring the catalyst activity. The oil product produced by the method has good quality, low sulfur content and higher product yield, but the method also has a series of problems: the pressure of the reaction is very high, generally a hydrogen atmosphere with about 40-150 atmospheric pressures is required, the temperature is 320-400 ℃, the investment of the whole set of hydrogenation device is large, the operation cost is high, the diesel oil cost is increased greatly, and the upper limit of the gasoline and diesel oil selling price is regulated by the government of China, so the profit of medium and small-scale oil refining enterprises is difficult to ensure. Meanwhile, the method needs to use expensive high-pressure hydrogen which is derived from steam reforming of natural gas, the whole process needs high water consumption and energy consumption, and simultaneously, a large amount of CO can be discharged₂And greenhouse gases, the technology is not economically advantageous.

In order to solve the economic pressure of the diesel hydrodesulfurization process, many researchers begin to explore the non-hydrodesulfurization technology of the diesel, and currently, a series of progresses are made, such as adsorption desulfurization, extraction desulfurization, complex desulfurization, oxidation desulfurization and the like. For example, CN1624081A discloses a diesel oxidation desulfurization method, which utilizes a series of complex catalysts, uses air as an oxidant, and adopts complex methods such as cooling, extraction and separation to achieve a diesel oil removal rate of 70%, and the method has a complex process flow. CN101173192A discloses a process for cutting diesel oil fraction into light diesel oil and heavy diesel oil, then treating the light diesel oil by hydrodesulfurization process and treating the heavy diesel oil by oxidative desulfurization process, so as to implement different treatment methods for different sulfides, which can improve the economy, but the process is too complex. CN101850237A discloses a preparation method of an adsorption desulfurizer, the desulfurizer has long treatment time, the reaction time of raw materials and the desulfurizer is about 1 hour, and the treatment capacity cannot be too large, so that the adsorption desulfurizer is not suitable for industrial amplification. CN102888244B discloses a method for producing bunker fuel oil, which uses a residual oil hydrorefining catalyst, a distillate oil hydrocracking catalyst, etc., and requires complicated reaction separation, re-blending, etc. to obtain the final product, and the method is also complicated. Therefore, the existing non-hydrodesulfurization technology still has a series of defects and shortcomings such as complex process flow, low processing speed and the like.

Wherein, the natural gas has the characteristics of large storage capacity and low cost. Meanwhile, the most main component in natural gas is methane CH₄It has the highest H/C molar ratio among all the organics, can provide more active H radicals if it can activate methane under certain conditions, and can be used as hydrogen source for hydrodesulfurization reaction without needing to go through the steam reforming step of methane to prepare H₂The method can greatly reduce the cost of the process, simplify the flow, reduce the energy consumption and the water consumption and further improve the comprehensive economic benefit. At present, the main application of natural gas is still to generate heat and electricity by combustion, so the economic value of the natural gas is low. If natural gas can be converted into chemicals, the economy can be greatly improved while the CO in the combustion process can be reduced₂And the emission of greenhouse gases. In recent years, a lot of reports of activating conversion of natural gas into chemicals have appeared, but high temperature is generally required and the conversion rate is relatively low, for example, in the methane oxidation coupling which refers to the ethylene reaction, the temperature is generally required to be higher than 700 DEGWarm and ethylene yields of less than 25% (Lunsford, j.h.angelw.chem.int.ed.engl., 1995,34, 970-980). There is therefore a need to develop new technologies for converting methane to chemicals under mild conditions.

Disclosure of Invention

The invention aims to provide a method for desulfurizing light oil in a non-hydrogenation or hydrogen atmosphere, which aims to solve a series of problems of high catalyst cost, complex process flow, use of expensive high-pressure hydrogen, large investment in fixed assets, low economic benefit and the like in the process of preparing clean oil products by hydrodesulfurization of light oil such as diesel oil and the like at present. The technology adopts a technology similar to hydrodesulfurization, but hydrogen is not used in the whole technological process, and the novel catalyst is utilized to remove S in light oil molecules under the atmosphere of methane, ethane, propane and the like, so that the sulfur content of the light oil is reduced at a milder condition in one step, and clean oil products are produced at low cost.

The invention is realized by adopting the following technical scheme:

a process for desulfurizing the light oil in non-hydrogenation or hydrogen atmosphere features that under the action of catalyst, the sulfur-contained compounds in the light oil are efficiently converted and removed in reactor to reduce the sulfur content in product oil.

The invention is further improved in that the light oil is one or a mixture of more of bunker fuel oil, catalytic diesel oil, straight-run diesel oil and catalytic gasoline.

The catalyst is further improved in that the catalyst is prepared by loading various metals on a formed carrier, the carrier material is preferably a silicon-aluminum molecular sieve which comprises one of FAU (Fabry-Perot unit), MFI (MFI) and BEA (BEA) molecular sieves, and the silicon-aluminum ratio ranges from 2.5:1 to 280: 1.

The further improvement of the invention is that the silicon-aluminum ratio of the MFI type molecular sieve is 20: 1-30: 1.

In a further development of the invention, the metals selected are two or more of Ga, Mo, Ag, Co, Ni, Ce, and the metal sources used are their corresponding soluble salts, including Ga (NO)₃)₃，(NH₄)₆Mo₇O₂₄，AgNO₃，Co(NO₃)₂，Ni(NO₃)₂And Ce (NO)₃)₃The metal loading, namely the weight ratio of the metal oxide to the carrier, is 1 to 20 weight percent, wherein the loading proportion is as follows: 1 wt% Ga, 1 wt% Ag and 10 wt% Mo.

The further improvement of the invention is that the preparation method of the catalyst comprises the following steps: firstly, dissolving soluble metal salt in water to form a metal precursor solution, then soaking the metal precursor solution into a porous carrier, drying at the temperature of 80-120 ℃ for 1-2 h, roasting at the temperature of 500-700 ℃ for 2-5 h, and controlling the temperature rise rate from room temperature to the roasting temperature to be 5-20 ℃/min.

In a further development of the invention, the support material is in the form of a powder or a shaped support; wherein, the carrier in the form of powder is directly made of molecular sieve material, and the preparation method of the formed carrier comprises the following steps: according to the molecular sieve material: methyl cellulose: adhesive: the weight ratio of the acid solution is 1: 0.05-0.2: 0.1-0.5 to form a mixture, molding, drying at 80-120 ℃ for 2h, roasting at 500-700 ℃ for 2-5 h, and controlling the heating rate from room temperature to roasting temperature to be 5-20 ℃/min; the binder comprises one or more of silica sol, aluminum sol and acidified pseudo-boehmite, and the acid solution comprises one or more of acetic acid and citric acid aqueous solutions, and the concentration of the acid solution is 5-10%.

The invention has the further improvement that the reactor is one or more of a batch type high-pressure kettle reactor, a continuous fixed bed reactor and a semi-batch reactor; in a batch autoclave reactor, wherein the mass ratio of light oil to catalyst is 100:1 to 1: 10; in the continuous fixed bed reactor, the liquid hourly space velocity of the light oil is 0.1h^-1To 5h^-1The reaction temperature is 350-450 ℃, and the reaction pressure is 1-50 atmospheric pressures.

A further improvement of the invention is that the reaction atmosphere is methane, ethane, propane or natural gas.

The invention has at least the following beneficial technical effects:

the invention provides a method for desulfurizing light oil in a non-hydrogenation or hydrogen atmosphere, which is characterized in that the light oil such as diesel oil with higher sulfur content is prepared into a low-sulfur product by a simple one-step reaction under the atmosphere of methane, ethane, propane or natural gas by using a simple catalyst, and the desulfurization rate is up to more than 90%. The invention realizes the high-efficiency removal of the S-containing compound in the light oil through a simple one-step reaction under the conditions of lower operation cost and mild reaction conditions, the liquid yield can reach 98 percent under the optimal conditions, and the desulfurization rate can reach more than 75 percent. The invention improves a series of problems of high catalyst cost, complex process flow, expensive high-pressure hydrogen, large investment of fixed assets, low economic benefit and the like in the conventional hydrodesulfurization technology, also solves a series of problems of low treatment efficiency, complex process flow, difficult control of oxidation depth and the like in newly developed adsorption desulfurization, extraction desulfurization, complex desulfurization, oxidation desulfurization and other technologies, and provides a new way for high-efficiency desulfurization of light oil, improvement of economic value of oil products and high-efficiency utilization of natural gas.

Detailed Description

The present invention will be further described with reference to the following examples.

The research of the invention finds that the coexistence of micromolecule alkane such as methane and the like and S-containing molecules in light oil can effectively promote the activation of methane under the action of a multi-metal supported catalyst in the atmosphere of methane, ethane, propane or natural gas, is beneficial to the breaking of C-S bonds in the light oil molecules, and can maintain lower coke and higher liquid yield while effectively reducing the S content.

Therefore, the invention provides a method for desulfurizing light oil in a non-hydrogenation or hydrogen atmosphere, which comprises the following steps:

(1) directly using a powder type carrier material or preparing a formed carrier material: the inorganic porous carrier comprises alumina, a silicon-aluminum molecular sieve, silica gel and the like, and the preparation method of the formed carrier comprises the following steps: mixing molecular sieve powder with methylcellulose and the acid solution according to the proportion of 1: 0.05-1: 0.2, adding the acid solution (comprising one or more of acetic acid and citric acid) according to the proportion of 1: 0.1-1: 0.5, uniformly stirring, adding a binder such as silica sol, alumina sol, acidified pseudo-boehmite and the like according to the proportion of 1: 0.1-1: 0.5, molding by a kneading and extruding machine, drying at the temperature of 80-120 ℃ for 2h, roasting at the temperature of 500-700 ℃ for 2-5 h, and heating at the rate of 5-20 ℃/min.

(2) Metal water-soluble salts including Ga (NO)₃)₃，(NH₄)₆Mo₇O₂₄，AgNO₃，Co(NO₃)₂，Ni(NO₃)₂And Ce (NO)₃) And the like, under the condition that the metal loading is 1-20 wt%, impregnating and loading the inorganic porous carrier in an equal volume, wherein the preferable loading proportion is as follows: 1 wt% Ga, 1 wt% Ag and 10 wt% Mo. Dissolving metal salt in water to form a metal precursor solution, then soaking the metal precursor solution into a porous carrier, standing for more than 2 hours to ensure that the soaking solution is uniformly dispersed, drying for 2 hours at the temperature of 80-120 ℃, roasting for 2-5 hours at the temperature of 500-700 ℃, and obtaining the catalyst at the heating rate of 5-20 ℃/min.

(3) One or a mixture of several of bunker fuel oil, catalytic diesel oil, straight-run diesel oil and catalytic gasoline is directly used as a reaction raw material, and the catalytic conversion performance of the bunker fuel oil, the catalytic diesel oil, the straight-run diesel oil and the catalytic gasoline is researched under the atmosphere of methane, ethane, propane or natural gas by using an intermittent high-pressure kettle type reactor, a continuous Fixed Bed Reactor (FBR) and the like.

(4) The reaction conditions used were: the temperature is 350-450 ℃, the reaction pressure is 1-50 atmospheric pressures, preferably 400 ℃ and 30 atmospheric pressures. In the batch autoclave reactor, the mass ratio of light oil to catalyst is 100:1 to 1:10, preferably 20:1, the Liquid Hourly Space Velocity (LHSV) of the light oil is about 0.1h^-1To about 5h^-1And preferably 1h^-1。

The invention uses methane, ethane, propane or natural gas atmosphere without hydrogen, and activates hydrocarbon molecules through the prepared multi-metal supported catalyst, thereby realizing the S-containing hydrocarbon molecules and alkane micromolecules in the synergistic cotransformation light oil, and the desulfurization rate can reach more than 75%.