阅读说明：本技术 渣油制备低硫石油焦的方法 (Method for preparing low-sulfur petroleum coke from residual oil ) 是由 刘必心 申海平 任磊 李子锋 陈煜� 于 2019-08-28 设计创作，主要内容包括：本发明涉及石油焦制备领域,公开了一种渣油制备低硫石油焦的方法,其中,所述方法包括：在氧化反应条件下,以及在溶剂和液相催化剂的存在下,将渣油与臭氧接触反应,得到含有氧化渣油的产物；在热转化条件下,将含有氧化渣油的产物进行热转化反应,得到低硫石油焦。本发明以渣油为原料通过先对渣油中含硫化合物在溶剂和液相催化剂存在下进行预氧化再结合热转化反应可以制备低硫石油焦。本发明采用清洁、绿色的臭氧作为氧化剂,成本低且工艺相对简单。(The invention relates to the field of petroleum coke preparation, and discloses a method for preparing low-sulfur petroleum coke from residual oil, wherein the method comprises the following steps: under the condition of oxidation reaction and in the presence of solvent and liquid-phase catalyst, residual oil and ozone are contacted and reacted to obtain a product containing oxidized residual oil; and carrying out thermal conversion reaction on the product containing oxidized residual oil under the thermal conversion condition to obtain the low-sulfur petroleum coke. The low-sulfur petroleum coke can be prepared by using residual oil as a raw material, pre-oxidizing sulfur-containing compounds in the residual oil in the presence of a solvent and a liquid-phase catalyst, and then combining a thermal conversion reaction. The invention adopts clean and green ozone as the oxidant, and has low cost and relatively simple process.)

1. A process for making low sulfur petroleum coke from residua, characterized in that the process comprises:

(1) under the condition of oxidation reaction and in the presence of solvent and liquid-phase catalyst, residual oil and ozone are contacted and reacted to obtain a product containing oxidized residual oil;

(2) and (2) carrying out thermal conversion reaction on the oxidized residual oil-containing product obtained in the step (1) under the thermal conversion condition to obtain low-sulfur petroleum coke.

2. The method as claimed in claim 1, wherein in the step (1), the weight ratio of the residual oil, the solvent and the liquid phase catalyst calculated by the effective components is 100-1000:1, preferably 100-500: 1.

3. The process of claim 1 or 2, wherein in step (1), the solvent is selected from one or more of benzene, toluene, chloroform, pyridine, N dimethylformamide, dichloromethane, catalytic diesel, coker diesel, reformed gasoline, and coker gasoline.

4. The process according to claim 1 or 2, wherein in step (1), the liquid phase catalyst is selected from one or more of nickel naphthenate, iron naphthenate, acetic acid, trifluoroacetic acid, benzoic acid, iron isooctanoate, and molybdenum isooctanoate.

5. The method as set forth in claim 1 or 2, wherein the amount of ozone used in step (1) is 100mL/min to 1000mL/min based on 100g of the total amount of the residue and the solvent.

6. The method according to any one of claims 1 to 5, wherein in step (1), the oxidation reaction conditions comprise: the reaction temperature is 35-110 ℃, and preferably 40-100 ℃; the reaction time is 2 to 20 hours, preferably 3 to 15 hours; the reaction pressure was normal pressure in gauge pressure.

7. The method as claimed in any one of claims 1 to 6, wherein the residual oil is contact-reacted with ozone in the presence of a solvent and a liquid phase catalyst in the step (1) in a manner comprising: heating residual oil to 90-200 deg.c, preferably 100-180 deg.c, mixing with solvent and liquid phase catalyst, and contacting with ozone for reaction.

8. The method of any of claims 1-7, wherein the method further comprises: before subjecting the oxidized residuum-containing product obtained in step (1) to a thermal conversion reaction, subjecting the product to fractional distillation to separate the solvent therein, and returning the separated solvent as at least a portion of the solvent used in step (1).

9. The method according to any one of claims 1 to 8, wherein in step (2), the conditions of the thermal conversion reaction comprise: the reaction temperature is 250-550 ℃, and preferably 370-525 ℃; the reaction time is 0.5 to 10 hours, preferably 1 to 5 hours; the reaction pressure was normal pressure in gauge pressure.

10. A process according to any one of claims 1 to 9 in which the resid is a vacuum resid.

Technical Field

The invention relates to the field of petroleum coke preparation, in particular to a method for preparing low-sulfur petroleum coke from residual oil, and more particularly relates to a method for preparing low-sulfur petroleum coke by carrying out oxidation pretreatment on residual oil and then carrying out thermal conversion reaction.

Background

With the heavy and inferior crude oil resources, the deep processing technology of heavy oil becomes the key point for the development of oil refining technology. At present, the processes of coking, heavy oil catalytic cracking, residual oil hydrogenation and the like are still taken as main processes, and delayed coking is the heavy oil conversion technology which is most applied in the world at present. Since the first set of delayed coking device was put into production in the United states in 1930, the delayed coking process developed rapidly, and the first set of delayed coking device in China was built and put into production in 1963. Delayed coking is one of the main means for processing inferior heavy oil, the processing capacity of the delayed coking is increased year by year, a large amount of petroleum coke is inevitably generated, only a part of high-quality petroleum coke can be used in the fields of electrodes, fuels and the like for aluminum and steel making, and in addition, the utilization problem of the petroleum coke with high sulfur generated by increasing sulfur-containing crude oil (such as the sulfur content of the petroleum coke produced by enterprises which process imported high-sulfur crude oil in China is more than 7 percent) needs to be solved urgently. How to reduce the sulfur content in high-sulfur petroleum coke generated by delayed coking is a very concerned problem for researchers and enterprises at home and abroad at present.

At present, aiming at the production of low-sulfur petroleum coke, the low-sulfur petroleum coke is produced mainly by raw material pretreatment, namely, by removing sulfur-containing compounds in raw oil and then feeding the treated raw material into a coking device.

The hydrotreating technology is the most widely used desulfurization technology in the petroleum refining industry at present, the hydrotreating not only requires a high-temperature high-pressure reaction environment but also requires a large amount of noble metal catalysts, and in addition, the hydrogen consumption of the hydrotreating is large, and the hydrotreating process undoubtedly causes a large burden on some refineries no matter from the source of hydrogen or from the aspect of economic cost, so the development of other desulfurization technologies is not slow.

In view of the large investment of the device and the operation strip of the hydrodesulfurization technologyThe parts are harsh and the like. Non-hydrodesulfurization techniques have received increasing attention. From the current research situation, non-hydrodesulfurization technologies mainly include adsorption desulfurization, complex desulfurization, extraction desulfurization, biological desulfurization, ionic liquid desulfurization, membrane separation desulfurization, alkylation desulfurization, and the like, and combinations of these technologies. Compared with other traditional non-hydrodesulfurization technologies (including adsorption desulfurization, complex desulfurization, extraction desulfurization and biological desulfurization), the oxidative desulfurization technology has the advantages of high desulfurization efficiency, mild reaction conditions and the like, and has become a research focus of the non-hydrodesulfurization technology in recent years and is paid more and more attention. Some foreign researchers and companies have made corresponding researches on the oxidative desulfurization technology, but the current researches mainly focus on the oxidative desulfurization of light oil products (gasoline and diesel oil), for example, the us Petro star company researches how to use a conversion-extraction desulfurization process (abbreviated as CED technology) to remove sulfur-containing compounds from diesel oil from 1996. At present, a novel continuous desulfurization combined process is developed, wherein H is used at normal pressure and below 100 DEG C₂O₂Acetic acid is used as oxidant, and sulfur in light oil is extracted through selective oxidation and liquid-liquid extraction to reduce sulfur content from 400 microgram/g to below 10 microgram/g. Further, for example, the Japanese Petroleum energy Co., Ltd (PEC) utilizes H₂O₂Acetic acid or carboxylic acid of trifluoroacetic acid is used as catalyst for oxidation, then washed by NaOH aqueous solution, and silica gel or alumina gel is used for absorbing oxidized sulfide, thus achieving the purpose of removing sulfide in diesel oil. The sulfur content of the diesel oil treated by the process can be reduced from 500-600 mu g/g to 10 mu g/g, the process conditions are mild (50 ℃, the reaction lh is carried out under 0.1 MPa), and the desulfurization rate is high, but the yield of the product is very high.

In addition, a few companies have studied the oxidative desulfurization technology of heavy oil, for example, the FlexUPTM oxidative desulfurization technology developed by the american aurora company can treat heavy sulfur-containing crude oil, oil sand bitumen and coal liquefaction oil, and can also treat residual oil from oil refinery, straight run wax oil, coker wax oil, catalytic cracking slurry oil, heavy cycle oil, and the like.

CN100429295C discloses a fixed bed oxidative desulfurization reaction method, which comprises the following three parts: (1) oxidizing petroleum fractions containing alkyl aromatic hydrocarbons to prepare organic peroxides; (2) mixing the petroleum fraction containing organic peroxide with the petroleum fraction to be desulfurized or chemical raw materials, and then oxidizing sulfur-containing compounds; (3) and (3) separation of oxidation products in distillate oil. The oxidant in the step (2) is organic peroxide prepared by the reaction of air or oxygen and distillate oil containing alkyl aromatic hydrocarbon, and the organic peroxide and the distillate oil to be oxidized are mixed in a fixed bed reactor (catalyst: supported molybdenum phosphorus oxide) for oxidation reaction; the oxidation products (sulfones and sulfoxides) were isolated by extraction with N, N-dimethylformamide.

CN103827264A discloses an oxidative desulfurization reaction in a fluid catalytic cracking process, wherein a raw hydrocarbon and a gaseous oxidant are fed into a riser reactor together to form a suspended substance (fluidized bed) with a regenerated mixed catalyst (FCC catalyst and oxidized S catalyst) in the riser, and the reaction temperature (conventional FCC reaction temperature 400-565 ℃) and pressure are controlled within the operating characteristics range of the catalytic cracking catalyst. Not only the catalytic cracking reaction but also the oxidation reaction of sulfur-containing compounds, and the resulting oxidized sulfide is decomposed at high temperature into SO₂And (4) discharging.

CN104395435A discloses a method for modifying a heteroatom-containing hydrocarbon stream by removing heteroatom contaminants, the method comprising: contacting a heteroatom-containing hydrocarbon feed with an oxidant and an immiscible acid; the oxidized heteroatom-containing hydrocarbon feed is contacted with at least one caustic and at least one selectivity promoter comprising an organic compound having at least one acidic proton prior to removal of the heteroatom contaminants from the heteroatom-containing hydrocarbon feed. The method disclosed in example 2 describes in detail: at 85 ℃, mixing straight-run light normal pressure oil and cumyl peroxide, carrying out contact reaction with a pellet-shaped titanyl catalyst in a fixed bed reactor to carry out oxidation reaction, and heating the reaction product to 50 ℃ again to carry out reaction. And separating by gravity to obtain light normal pressure oil with light phase with fully reduced heteroatoms and heavy phase by-products (containing oxidation products). In addition, the cumyl peroxide is recovered and reused by means of vacuum distillation.

Therefore, the related reports on the oxidation desulfurization of the residual oil are few, and only the report is introduced in CN104395435A of Odela corporation in the United states. Therefore, the technology for oxidative desulfurization of residual oil, particularly the technology for preparing low-sulfur petroleum coke from residual oil, is still under further research and development.

Disclosure of Invention

The invention aims to overcome the problem of residual oil oxidative desulfurization in the prior art, and provides a method for preparing low-sulfur petroleum coke by oxidative desulfurization of residual oil.

In the prior art, the method for preparing petroleum coke by using residual oil is generally to directly perform thermal conversion reaction on the residual oil. However, if low sulfur content of the petroleum coke is desired, further desulfurization of the residuum is required. The inventor of the invention finds that when the residual oil is subjected to oxidative desulfurization treatment by adopting the prior art, the residual oil has a boiling point of over 500 ℃ and a high viscosity, and the mass transfer efficiency of the oxidative desulfurization reaction of the residual oil is remarkably reduced at the oxidative desulfurization temperature of usually not higher than 130 ℃, so that the oxidative desulfurization effect of the residual oil is poor. Therefore, how to achieve effective oxidative desulfurization of residual oil is the key to making low sulfur petroleum coke from residual oil. In addition, if the solid-phase catalyst is adopted for catalytic oxidative desulfurization according to the teaching of the prior art, not only the catalyst residue in the oxidation product is high, but also the catalyst is extremely easy to inactivate because heavy oil macromolecules such as asphaltene exist in the residual oil and the like and the catalyst is greatly damaged, so that on one hand, continuous residual oil oxidative desulfurization treatment cannot be realized, and on the other hand, the solid-phase catalyst is not favorable for recycling. Therefore, the inventor of the invention can well realize the sufficient oxidation of sulfur-containing substances in the residual oil, such as the oxidation of thiophene into sulfone, by mixing the residual oil with the solvent to reduce the viscosity of the residual oil system so as to ensure the mass transfer efficiency of the system and on the basis of the reduction, the inventor adopts the liquid-phase catalyst to catalyze, oxidize and desulfurize. In the subsequent thermal conversion reaction process, the oxidation product is converted into sulfur dioxide under the thermal conversion condition and is fully removed, so that low-sulfur petroleum coke is obtained, and the problem that the catalyst is difficult to filter after reaction due to the adoption of a solid-phase catalyst is also avoided.

In order to achieve the above object, the present invention provides a method for preparing low sulfur petroleum coke from residual oil, wherein the method comprises:

(1) under the condition of oxidation reaction and in the presence of solvent and liquid-phase catalyst, residual oil and ozone are contacted and reacted to obtain a product containing oxidized residual oil;

(2) and (2) carrying out thermal conversion reaction on the oxidized residual oil-containing product obtained in the step (1) under the thermal conversion condition to obtain low-sulfur petroleum coke.

The method provided by the invention can prepare the low-sulfur petroleum coke by using the residual oil as the raw material under mild conditions through pre-oxidizing the sulfur-containing compounds in the residual oil and combining with a thermal conversion (coking) reaction. The invention adopts clean and green ozone as the oxidant, and has low cost and relatively simple process. In addition, the method provided by the invention preferably recycles the solvent through a fractionating device after the oxidation reaction, and can further reduce the reaction cost.

Drawings

FIG. 1 is a schematic diagram of a process for preparing low-sulfur petroleum coke from residual oil, which mainly comprises two parts of oxidizing pretreatment of residual oil and thermal conversion of oxidized products to remove sulfur.

Description of the reference numerals

1-a resid feed vessel in which resid, solvent, and catalyst are mixed;

2-an oxidation reactor, wherein the ozone is prepared by introducing oxygen into an ozone generator;

3-solvent fractionation equipment;

4-oxidation residual oil thermal conversion device.

Detailed Description

The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.

In the present invention, the "low sulfur petroleum coke" refers to petroleum coke having a sulfur content of not more than 3 wt%.

According to the invention, the method for preparing low-sulfur petroleum coke from residual oil comprises the following steps:

(1) under the condition of oxidation reaction and in the presence of solvent and liquid-phase catalyst, residual oil and ozone are contacted and reacted to obtain a product containing oxidized residual oil;

(2) and (2) carrying out thermal conversion reaction on the oxidized residual oil-containing product obtained in the step (1) under the thermal conversion condition to obtain low-sulfur petroleum coke.

According to the present invention, the residual feedstock is a residual feedstock that can be suitably used in the process of the present invention to produce low sulfur petroleum coke, e.g., the residual feedstock is a vacuum residue and the residual feedstock has a sulfur content of at least 5 wt.%. The low-sulfur petroleum coke with the sulfur content of not higher than 3 weight percent can be prepared by using residual oil as a raw material and combining pre-oxidation of sulfur-containing compounds in the residual oil with thermal conversion reaction.

According to the present invention, in the step (1), the solvent is various solvents capable of diluting and/or dissolving the residual oil under the oxidation condition to improve the fluidity of the residual oil, thereby achieving an improvement in the mass transfer efficiency of the oxidation reaction during the oxidation reaction and an improvement in the desulfurization effect of the residual oil. Preferably, the solvent is selected from one or more of benzene, toluene, chloroform, pyridine, N-dimethylformamide, dichloromethane, catalytic diesel, coker diesel, reformate gasoline and coker gasoline.

According to the present invention, in the step (1), the liquid phase catalyst is various liquid phase catalysts capable of catalyzing oxidation of the residue. The liquid phase catalyst refers to a catalyst generally used in the form of a liquid phase, for example, a catalyst itself is liquid, or a mixed solution of a catalyst and a solvent. Preferably, the liquid phase catalyst is selected from one or more of nickel naphthenate, iron naphthenate, acetic acid, trifluoroacetic acid, benzoic acid, iron isooctanoate, and molybdenum isooctanoate.

According to the invention, in the step (1), the dosage of the solvent is based on the improvement of the fluidity of the residual oil, and the dosage of the liquid phase catalyst is based on the catalysis of the oxidation of the residual oil, namely the oxidation of sulfur-containing compounds in the residual oil. Preferably, the weight ratio of the residual oil, the solvent and the catalyst based on the effective components is 100-1000:1, and more preferably 100-500: 1. Wherein the effective component of the liquid phase catalyst means the amount of solute or pure substance (catalyst) in the liquid phase catalyst when the liquid phase catalyst is used in the form of a solution or is liquid itself.

According to the invention, in the step (1), the invention adopts ozone as the oxidant, so that the process is simple, the ozone is obtained in a simple and convenient manner, for example, the ozone can be prepared by introducing oxygen into an ozone generator, and the ozone generator has the advantages of environmental friendliness, cleanness and low cost. The dosage of the ozone is based on the oxidation of sulfur-containing compounds in the residual oil, and preferably, the dosage of the ozone is 100mL/min-1000mL/min based on the total amount of 100g of the residual oil and the solvent. The source of the ozone is not particularly limited in the present invention, and the ozone can be obtained by ozone instrument preparation or can be obtained commercially. Wherein, the concentration of the ozone prepared by the ozone instrument is generally 80-120mg/L, and the concentration of the prepared ozone in the specific embodiment is 100 mg/L.

According to the present invention, in the step (1), the conditions of the oxidation reaction generally include a reaction temperature and a reaction time, and a reaction pressure. The conditions for the oxidation reaction can be selected from a wide range and can be selected according to the routine reference in the art. Preferably, the reaction temperature of the oxidation reaction is 35 to 110 ℃, more preferably 40 to 100 ℃; the reaction time of the oxidation reaction is 2 to 20 hours, more preferably 3 to 15 hours; the reaction pressure of the oxidation reaction was normal pressure in terms of gauge pressure.

According to the present invention, since the boiling point of the residue is generally above 500 ℃ and the viscosity is large. Therefore, in order to further improve the mass transfer effect of the reaction and improve the effect of oxidative desulfurization of the residual oil, the residual oil needs to be preheated first so that the residual oil can flow. Therefore, in the preferred case, in the step (1), the residual oil is reacted with ozone in contact with the solvent and the liquid phase catalyst in a manner comprising: heating residual oil to 90-200 deg.c, preferably 100-180 deg.c, mixing with solvent and liquid phase catalyst, and contacting with ozone for reaction. The heated residual oil, the solvent and the liquid phase catalyst can be uniformly mixed under stirring, and the specific stirring condition is not particularly limited as long as the three components are uniformly mixed.

According to the invention, the method further comprises: before subjecting the oxidized residuum-containing product obtained in step (1) to a thermal conversion reaction, subjecting the product to fractional distillation to separate the solvent therein, and returning the separated solvent as at least a portion of the solvent used in step (1). The cost of the reaction can be further reduced by fractionating the solvent for reuse. Wherein the conditions of the fractionation may be selected based on the boiling points of the different solvents to effect separation of the solvent from the product containing the oxidized sulfur-containing compounds.

According to the invention, in the step (2), the oxidized sulfur-containing compounds in the oxidized residual oil in the step (1) can be further decomposed and removed through a thermal conversion reaction, and meanwhile, low-sulfur petroleum coke is prepared through a coking process. Wherein, the thermal conversion reaction refers to the process of deep cracking and condensation of organic matters and carbonization zooming at high temperature. Specifically, in the step (2), the conditions of the thermal conversion reaction generally include a reaction temperature and a reaction time, and a reaction pressure. The conditions for the thermal conversion reaction can be selected from a wide range and can be selected according to the routine skill in the art. Preferably, the reaction temperature of the thermal conversion reaction is 250 ℃ to 550 ℃, more preferably 370 ℃ to 525 ℃; the reaction time of the thermal conversion reaction is 0.5 to 10 hours, more preferably 1 to 5 hours; the reaction pressure was normal pressure in gauge pressure.

The present invention will be described in further detail below with reference to fig. 1.

According to a specific embodiment of the present invention, the method for preparing low sulfur petroleum coke from residual oil comprises: heating residual oil to make the residual oil be able to flow, uniformly mixing the heated residual oil with solvent and liquid-phase catalyst in residual oil raw material tank 1, then feeding the mixture into oxidation reactor 2, and making the mixture contact with ozone prepared by ozone instrument to make oxidation reaction. The oxidized residuum containing product is passed to a solvent fractionation unit 3 for fractionation to effect distillative separation of solvent therefrom and to return separated solvent to at least a portion of the solvent used in residuum feed drum 1. And (3) feeding the oxidized residual oil subjected to solvent separation into an oxidized residual oil thermal conversion device 4 for thermal conversion reaction to prepare low-sulfur petroleum coke.

The present invention will be described in detail below by way of examples.

In the following examples and comparative examples:

the amount of the catalyst is given as the effective amount, the ozone is prepared by an ozone generator, and the concentration of the prepared ozone is 100 mg/L;

the feedstock used was vacuum residue, the properties of which are shown in table 1;

the sulfur content of petroleum coke is determined by elemental analysis;

a small-sized simulated coking device is adopted in the thermal conversion experiment of the oxidation residual oil.

TABLE 1

Example 1

This example illustrates the process of the present invention for making low sulfur petroleum coke from resid.

The vacuum residue is put into an oven and heated to 140 ℃ until the residue can flow, 50g of the residue is poured into a 250mL three-neck flask while the residue is hot, 50g of solvent toluene is added, 0.2g of catalyst benzoic acid is added at the same time, and the residue, the solvent and the catalyst are stirred to be fully mixed. Ozone (based on the total amount of 100g of residual oil and solvent, the flow rate of ozone is 150ml/min, the concentration of ozone is 100mg/L) is introduced into the three-neck flask for oxidation reaction, the reaction temperature is 40 ℃, and the reaction time is 5 hours. After the reaction is finished, the solvent toluene in the residual oil system is distilled off. And respectively taking out 1g of oxidized residual oil and original residual oil, and carrying out a residual oil thermal conversion experiment on a small-sized green coke evaluation device, wherein the reaction temperature is 450 ℃ and the reaction time is 1 hour, so as to obtain coke. And finally, carrying out sulfur content test on the obtained coke, and comparing the change of the sulfur content in the petroleum coke before and after oxidation, wherein the specific result is shown in table 2.

Example 2

This example illustrates the process of the present invention for making low sulfur petroleum coke from resid.

Heating vacuum residue in an oven to 150 ℃ until the residue can flow, pouring 50g of residue into a 250mL three-neck flask while the residue is hot, adding 50g of solvent catalytic diesel oil and 0.1g of catalyst iron isooctanoate, and stirring to fully mix the residue, the solvent and the catalyst. Ozone (based on the total amount of 100g of residual oil and solvent, the flow rate of ozone is 500ml/min, the concentration of ozone is 100mg/L) is introduced into the three-neck flask to carry out oxidation reaction, the reaction temperature is 50 ℃, and the reaction time is 7 hours. After the reaction is finished, the solvent in the residual oil system is distilled off to catalyze the diesel oil. And respectively taking out 1g of oxidized residual oil and original residual oil, and carrying out a residual oil thermal conversion experiment on a small-sized green coke evaluation device at the reaction temperature of 500 ℃ for 1.5 hours to obtain coke. And finally, carrying out sulfur content test on the obtained coke, and comparing the change of the sulfur content in the petroleum coke before and after oxidation, wherein the specific result is shown in table 2.

Example 3

This example illustrates the process of the present invention for making low sulfur petroleum coke from resid.

The vacuum residue is put into an oven and heated to 120 ℃ until the residue can flow, 50g of the residue is poured into a 250mL three-neck flask while the residue is hot, 50g of solvent toluene is added, 0.4g of catalyst molybdenum isooctanoate is added at the same time, and the residue, the solvent and the catalyst are stirred to be fully mixed. Ozone (based on the total amount of 100g of residual oil and solvent, the flow rate of the ozone is 700ml/min, the concentration of the ozone is 100mg/L) is introduced into the three-neck flask for oxidation reaction, the reaction temperature is 45 ℃, and the reaction time is 8 hours. After the reaction is finished, evaporating the solvent toluene in the residual oil system, respectively taking out 1g of oxidized residual oil and original residual oil, and carrying out a residual oil thermal conversion experiment on a small-sized green coke evaluation device, wherein the reaction temperature is 470 ℃ and the reaction time is 2 hours, so as to obtain coke. And finally, carrying out sulfur content test on the obtained coke, and comparing the change of the sulfur content in the petroleum coke before and after oxidation, wherein the specific result is shown in table 2.

Example 4

This example illustrates the process of the present invention for making low sulfur petroleum coke from resid.

Heating the vacuum residue in an oven to 170 ℃ until the residue can flow, pouring 50g of the residue into a 250mL three-neck flask while the residue is hot, adding 50g of solvent N, N-dimethylformamide and 0.15g of catalyst trifluoroacetic acid, and stirring to fully mix the residue, the solvent and the catalyst. The three-neck flask is filled with ozone (based on the total amount of 100g of residual oil and solvent, the flow rate of the ozone is 500ml/min, the concentration of the ozone is 100mg/L) to carry out oxidation reaction, the reaction temperature is 65 ℃, and the reaction time is 5 hours. After the reaction is finished, the solvents N and N dimethylformamide in the residual oil system are evaporated, 1g of oxidized residual oil and original residual oil are respectively taken out, a residual oil thermal conversion experiment is carried out on a small-sized green coke evaluation device, the reaction temperature is 380 ℃, and the reaction time is 1 hour, so that coke is obtained. And finally, carrying out sulfur content test on the obtained coke, and comparing the change of the sulfur content in the petroleum coke before and after oxidation, wherein the specific result is shown in table 2.

Example 5

This example illustrates the process of the present invention for making low sulfur petroleum coke from resid.

Heating vacuum residuum in an oven to 140 ℃ until the residuum can flow, pouring 50g of residuum into a 250mL three-neck flask while the residuum is hot, adding 50g of solvent pyridine, adding 0.2g of catalyst iron naphthenate, and stirring to fully mix the residuum, the solvent and the catalyst. Ozone (based on the total amount of 100g of residual oil and solvent, the flow rate of ozone is 150ml/min, the concentration of ozone is 100mg/L) is introduced into the three-neck flask for oxidation reaction, the reaction temperature is 40 ℃, and the reaction time is 5 hours. After the reaction is finished, the solvent pyridine in the residual oil system is distilled off. And respectively taking out 1g of oxidized residual oil and original residual oil, and carrying out a residual oil thermal conversion experiment on a small-sized green coke evaluation device, wherein the reaction temperature is 450 ℃ and the reaction time is 1 hour, so as to obtain coke. And finally, carrying out sulfur content test on the obtained coke, and comparing the change of the sulfur content in the petroleum coke before and after oxidation, wherein the specific result is shown in table 2.

The vacuum residue is put into an oven and heated to 140 ℃ until the residue can flow, 50g of the residue is poured into a 250mL three-neck flask while the residue is hot, 50g of solvent toluene is added, 0.2g of catalyst benzoic acid is added at the same time, and the residue, the solvent and the catalyst are stirred to be fully mixed. Ozone (based on the total amount of 100g of residual oil and solvent, the flow rate of ozone is 150ml/min, the concentration of ozone is 100mg/L) is introduced into the three-neck flask for oxidation reaction, the reaction temperature is 40 ℃, and the reaction time is 5 hours. After the reaction is finished, the solvent toluene in the residual oil system is distilled off. And respectively taking out 1g of oxidized residual oil and original residual oil, and carrying out a residual oil thermal conversion experiment on a small-sized green coke evaluation device, wherein the reaction temperature is 450 ℃ and the reaction time is 1 hour, so as to obtain coke. And finally, carrying out sulfur content test on the obtained coke, and comparing the change of the sulfur content in the petroleum coke before and after oxidation, wherein the specific result is shown in table 2.

Example 6

This example illustrates the process of the present invention for making low sulfur petroleum coke from resid.

Vacuum residuum is put into an oven and heated to 140 ℃ until the residuum can flow, 50g of residuum is poured into a 250mL three-neck flask while the residuum is hot, 400g of solvent coker gasoline is added, 0.5g of catalyst acetic acid is added at the same time, and the residuum, the solvent and the catalyst are stirred to be fully mixed. The three-neck flask is filled with ozone (based on the total amount of 450g of residual oil and solvent, the ozone flow is 675ml/min) to carry out oxidation reaction, the reaction temperature is 40 ℃, and the reaction time is 5 hours. After the reaction is finished, the solvent coking gasoline in the residual oil system is distilled off. And respectively taking out 1g of oxidized residual oil and original residual oil, and carrying out a residual oil thermal conversion experiment on a small-sized green coke evaluation device, wherein the reaction temperature is 450 ℃ and the reaction time is 2 hours to obtain coke. And finally, carrying out sulfur content test on the obtained coke, and comparing the change of the sulfur content in the petroleum coke before and after oxidation, wherein the specific result is shown in table 2.

Comparative example 1

This comparative example is illustrative of a reference process for making petroleum coke from residuum.

The vacuum residue is put into an oven and heated to 140 ℃ until the residue can flow, 50g of the residue is poured into a 250mL three-neck flask while the residue is hot, 50g of solvent toluene is added, and the mixture is stirred to fully mix the residue and the toluene. Ozone (based on the total amount of 100g of residual oil and solvent, the flow rate of ozone is 150ml/min, the concentration of ozone is 100mg/L) is introduced into the three-neck flask for oxidation reaction, the reaction temperature is 65 ℃, and the reaction time is 5 hours. After the reaction is finished, the solvent toluene in the residual oil system is distilled off. And respectively taking out 1g of oxidized residual oil and original residual oil, and carrying out a residual oil thermal conversion experiment on a small-sized green coke evaluation device at the reaction temperature of 450 ℃ for 1 hour to obtain coke. And finally, carrying out sulfur content test on the obtained coke, and comparing the change of the sulfur content in the petroleum coke before and after oxidation, wherein the specific result is shown in table 2.

Comparative example 2

This comparative example is illustrative of a reference process for making petroleum coke from residuum.

Vacuum residuum is put into an oven and heated to 140 ℃ until the residuum can flow, 50g of residuum is poured into a 250mL three-neck flask while the residuum is hot, 0.2g of catalyst benzoic acid is added, and the residuum and the catalyst are stirred to be fully mixed. Ozone (based on the total amount of 100g of residual oil and solvent, the flow rate of ozone is 150ml/min, the concentration of ozone is 100mg/L) is introduced into the three-neck flask for oxidation reaction, the reaction temperature is 40 ℃, and the reaction time is 5 hours. After the reaction is finished, the solvent toluene in the residual oil system is distilled off. And respectively taking out 1g of oxidized residual oil and original residual oil, and carrying out a residual oil thermal conversion experiment on a small-sized green coke evaluation device at the reaction temperature of 450 ℃ for 1 hour to obtain coke. And finally, carrying out sulfur content test on the obtained coke, and comparing the change of the sulfur content in the petroleum coke before and after oxidation, wherein the specific result is shown in table 2.

Comparative example 3

This comparative example is illustrative of a reference process for making petroleum coke from residuum.

And (3) directly carrying out a residue oil thermal conversion experiment on the vacuum residue oil on a small-sized green coke evaluation device, wherein the reaction temperature is 500 ℃, and the reaction time is 2 hours, so as to obtain the coke. Finally, the obtained coke was subjected to sulfur content test, and the specific results are shown in table 2.

TABLE 2

As can be seen from the results in table 2, the process of the present invention can produce low sulfur petroleum coke with a sulfur content reduced by at least 12.63% compared to the sulfur content of the residual oil feedstock.

The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.