阅读说明：本技术 一种降低催化裂化进料油中硫、氮含量的串联处理工艺 (Series treatment process for reducing sulfur and nitrogen content in catalytic cracking feed oil ) 是由 朱文帅 朱昊男 吴沛文 巢艳红 邓畅 于 2021-07-07 设计创作，主要内容包括：本发明公开了一种降低催化裂化进料油(FCC)中总硫、总氮含量的串联处理工艺。本发明可使催化裂化进料油中硫含量降低60％～99％、氮含量降低80％～100％,处理过后低硫低氮含量的催化裂化进料油再进入加氢预处理装置、亦或是直接进入催化裂化装置,不仅能够在一定程度上降低加氢预处理装置的操作运行成本、提升生产安全性,而且能够提高下游产物催化裂化汽、柴油的产品质量,以适应FCC原料愈来愈劣质化的现状。本发明中使用的萃取剂均能够通过真空旋蒸的方式完成高效回收再利用。(The invention discloses a series treatment process for reducing the total sulfur and total nitrogen content in catalytic cracking feed oil (FCC). The invention can reduce the sulfur content in the catalytic cracking feed oil by 60-99 percent and the nitrogen content by 80-100 percent, and the treated catalytic cracking feed oil with low sulfur and low nitrogen content enters the hydrogenation pretreatment device or directly enters the catalytic cracking device, thereby not only reducing the operation cost of the hydrogenation pretreatment device to a certain extent and improving the production safety, but also improving the product quality of downstream products of catalytic cracking gasoline and diesel oil so as to adapt to the current situation that the FCC raw material is degraded more and more. The extracting agent used in the invention can be efficiently recycled and reused in a vacuum rotary evaporation mode.)

1. a series treatment process for reducing the contents of sulfur and nitrogen in catalytic cracking feed oil is characterized by comprising the following steps:

(1) mixing an extracting agent and catalytic cracking feed oil and then preheating;

(2) fully oscillating the preheated mixture in the step (1) to ensure that an oil phase is fully contacted with an extractant phase as much as possible, and standing or centrifuging to ensure that the two phases are layered;

(3) repeating the steps (1) to (2) for a plurality of times to obtain the oil product after the upper layer treatment;

(4) transferring the oil product treated in the step (3) to a reaction device, adding an oxidant and a catalyst containing transition metal, stirring and reacting at a certain temperature for a certain reaction time, and separating an oil phase, a water phase and a catalyst phase after the reaction is finished;

(5) mixing the oil phase obtained in the step (4) with an extracting agent, and preheating in a water bath;

(6) fully shaking the preheated mixture in the step (5) to ensure that the oil phase is fully contacted with the extractant phase as much as possible, and standing or centrifuging to ensure that the two phases are layered;

(7) and (4) repeating the mixed centrifugal layering operation in the steps (5) - (6) for a plurality of times to obtain the oil product after the upper layer is treated, recovering the extractant phase at the lower layer, and recovering the extractant by distillation.

2. The tandem treatment process for reducing the sulfur and nitrogen content in the catalytic cracking feed oil according to claim 1, wherein in the step (1), the catalytic cracking feed oil is a coker gas oil CGO produced in the delayed coking of heavy oil and a vacuum gas oil VGO produced in the vacuum distillation of heavy oil in the industrial petroleum refining process, and the ratio of the volume ratio of the coker gas oil CGO to the vacuum gas oil VGO is as follows: VGO is a mixture mixed in a ratio of 0-0.5: 1.

3. The tandem process for reducing the sulfur and nitrogen content in catalytic cracking feed oil according to claim 1, wherein in the steps (1) to (8), the extracting agent comprises any one or a mixture of several extracting agents selected from furfural, N-Dimethylformamide (DMF) and N-methylpyrrolidone (NMP) in any proportion;

wherein, in the step (1), the volume ratio of the catalytic cracking feed oil to the extracting agent is 1: 1-5;

in the step (5), the volume ratio of the oil phase to the extractant is 1:1 to 5.

4. The tandem treatment process for reducing the sulfur and nitrogen content in catalytic cracking feed oil according to claim 1, wherein in the step (1) and the step (5), the preheating temperature is 30-150 ℃ and the preheating time is 1-30 minutes.

5. The tandem treatment process for reducing the sulfur and nitrogen content in catalytic cracking feed oil according to claim 1, wherein in the step (2) and the step (6), the rotation speed of the centrifugation is 1000-15000 rpm, and the time of the centrifugation is 1-15 minutes.

6. The reduced catalysis of claim 1The series treatment process of the sulfur and nitrogen content in the cracking feed oil is characterized in that in the step (4), the oxidant comprises H₂O₂One or a mixture of a plurality of oxidants of aqueous solution, air and high purity oxygen in any proportion; the dosage ratio is respectively as follows:

H₂O₂the concentration of the aqueous solution is 3 wt.% to 30 wt.%, and the addition amount is H added into every 5mL of oil product₂O₂0.1-5 mL of aqueous solution;

the air flow rate is 150-200 mL/min^-1；

The flow rate of the high-purity oxygen is 50-150 mL/min^-1。

7. The in-line process for reducing the sulfur and nitrogen content of a catalytic cracking feed oil according to claim 1, wherein in step (4), the transition metal-containing catalyst includes, but is not limited to, metal-organic framework material type catalyst UiO-66, molybdenum trioxide, tungsten trioxide, phosphotungstic acid, phosphomolybdic acid, high entropy metal oxide MgNiCuZnCoO, high entropy metal oxide (CoCrFeMnNi)₃O₄Any one or a mixture of several catalysts in any proportion;

the addition amount of the catalyst containing the transition metal is 0.1-0.5 g of the catalyst corresponding to every 5mL of the oil product.

8. The tandem treatment process for reducing the sulfur and nitrogen content in catalytic cracking feed oil according to claim 1, wherein in the step (4), the reaction temperature is 30-120 ℃, the reaction time is 30-300 minutes, and the stirring speed is 100-1100 rpm.

9. The tandem process for reducing the sulfur and nitrogen content in the catalytic cracking feed oil according to claim 1, wherein in the step (7), the method for recovering the extracting agent by distillation comprises any one or two processes of vacuum rotary distillation and inert gas atmosphere atmospheric distillation in any sequence;

when the recovery object is furfural or DMF, heating in a constant-temperature oil bath at 100-150 ℃ under the reduced-pressure rotary evaporation condition of-0.1 MPa;

when NMP is used as a recycling object, the NMP is heated in a constant-temperature oil bath under the conditions of-0.1 MPa of reduced pressure rotary evaporation and 140-170 ℃, and the treatment time is 15-30 minutes.

10. The catalytic cracking feed oil treated by the series treatment process as claimed in any one of claims 1 to 9, wherein the sulfur content and the nitrogen content are reduced by 60% to 100%.

Technical Field

The invention relates to a pretreatment process of catalytic cracking raw oil, in particular to a method capable of effectively reducing the content of sulfur and nitrogen in the catalytic cracking raw oil.

Background

Catalytically cracked feed oil (FCC) processing is reported to be an important component of deep secondary processing of crude oil. On the one hand, in the major industrial countries which are the first turn of the world, China needs to process hundreds of millions of tons of FCC raw materials every year, and the huge processing amount causes the catalytic cracking regenerator to discharge a large amount of SO-containing gas to the atmosphere every year_x、NO_xSmoke, causing serious environmental problems; on the other hand, a considerable number of industrial FCC feedstock hydrogenation pretreatment devices currently require not only high-temperature, high-hydrogen partial-pressure operating conditions, but also a limited effect on removing nitrides from oils. A large number of sulfur-containing and nitrogen-containing species remaining in the oil product can affect the downstream products of catalytic cracking: such as the quality of catalytic cracking gasoline and diesel oil, and can cause irreversible poisoning of the catalytic cracking catalyst. Along with the increasing price difference of high and low sulfur crude oil in recent years, the yield of poor FCC raw oil is gradually increased.

The FCC raw material pretreatment process which can not only meet the increasingly strict environmental protection requirement, but also improve the production safety and effectively reduce the oil refining cost is designed, thereby being beneficial to further improving the quality of petroleum products in China and the development of environmental protection career.

Disclosure of Invention

The invention aims to design a serial FCC raw oil pretreatment process, and the process is used for real FCC raw oil pretreatment so as to achieve the purpose of effectively reducing the contents of sulfur and nitrogen compounds in the FCC raw oil.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a series treatment process for reducing the contents of sulfur and nitrogen in catalytic cracking feed oil comprises the following steps:

(1) mixing an extracting agent and catalytic cracking feed oil and then preheating;

(2) fully oscillating the preheated mixture in the step (1) to ensure that an oil phase is fully contacted with an extractant phase as much as possible, and standing or centrifuging to ensure that the two phases are layered;

(3) repeating the steps (1) to (2) for a plurality of times to obtain the oil product after the upper layer treatment;

(4) transferring the oil product treated in the step (3) to a reaction device, adding an oxidant and a catalyst containing transition metal, stirring and reacting at a certain temperature for a certain reaction time, and separating an oil phase, a water phase and a catalyst phase after the reaction is finished;

(5) mixing the oil phase obtained in the step (4) with an extracting agent, and preheating in a water bath;

(6) fully shaking the preheated mixture in the step (5) to ensure that the oil phase is fully contacted with the extractant phase as much as possible, and standing or centrifuging to ensure that the two phases are layered;

(7) and (4) repeating the mixed centrifugal layering operation in the steps (5) - (6) for a plurality of times to obtain the oil product after the upper layer is treated, recovering the extractant phase at the lower layer, and recovering the extractant by distillation.

In the step (1), the catalytic cracking feed oil is a coking wax oil CGO produced in the delayed coking of heavy oil and a vacuum wax oil VGO produced in the vacuum distillation of heavy oil in the refining process of industrial petroleum, and the catalytic cracking feed oil is prepared by mixing the following components in percentage by volume (CGO): VGO is a mixture mixed in a ratio of 0-0.5: 1.

In the steps (1) - (8), the extracting agent includes but is not limited to any one or a mixture of several extracting agents of furfural, N-Dimethylformamide (DMF) and N-methylpyrrolidone (NMP) mixed according to any proportion;

wherein, in the step (1), the volume ratio of the catalytic cracking feed oil to the extracting agent is 1: 1-5;

in the step (5), the volume ratio of the oil phase to the extractant is 1:1 to 5.

In the step (1) and the step (5), the preheating temperature is 30-150 ℃, and the preheating time is 1-30 minutes.

In the step (2) and the step (6), the rotating speed of the centrifugation is 1000-15000 rpm, and the time of the centrifugation is 1-15 minutes.

In step (4), the oxidizing agent comprises H₂O₂One or a mixture of a plurality of oxidants of aqueous solution, air and high purity oxygen in any proportion; the dosage ratio is respectively as follows:

H₂O₂the concentration of the aqueous solution is 3 wt.% to 30 wt.%, and the addition amount is H added into every 5mL of oil product₂O₂0.1-5 mL of aqueous solution;

the air flow rate is 150-200 mL/min^-1；

The flow rate of the high-purity oxygen is 50-150 mL/min^-1。

In the step (4), the transition metal-containing catalyst includes, but is not limited to, a metal-organic framework material type catalyst UiO-66, molybdenum trioxide, tungsten trioxide, phosphotungstic acid, phosphomolybdic acid, high entropyMetal oxide MgNiCuZnCoO, high entropy metal oxide (CoCrFeMnNi)₃O₄Any one or a mixture of several catalysts in any proportion;

the addition amount of the catalyst containing the transition metal is 0.1-0.5 g of the catalyst corresponding to every 5mL of the oil product.

In the step (4), the reaction temperature is 30-120 ℃, the reaction time is 30-300 minutes, and the stirring speed is 100-1100 rpm.

In the step (7), the method for distilling and recovering the extractant comprises any one or two processes of reduced pressure rotary distillation and inert gas atmosphere normal pressure distillation in series connection in any order;

when the recovery object is furfural or DMF, heating in a constant-temperature oil bath at 100-150 ℃ under the reduced-pressure rotary evaporation condition of-0.1 MPa;

when NMP is used as a recycling object, the NMP is heated in a constant-temperature oil bath under the conditions of-0.1 MPa of reduced pressure rotary evaporation and 140-170 ℃, and the treatment time is 15-30 minutes.

The sulfur content and the nitrogen content of the catalytic cracking feed oil treated by the series treatment process are reduced by 60-100%, and the color of the oil product is clear.

The invention has the beneficial effects that:

the invention utilizes simple series pretreatment process to obtain FCC feed oil with low sulfur and nitrogen content after treatment. The process flow is simple to operate, the reaction condition is mild, the extracting agent is cheap and easy to obtain, and complex and expensive instruments and equipment are not needed. The process flow comprises the step of efficiently recycling the extracting agent, so that the economical efficiency and the environmental friendliness of the process are further improved.

Drawings

FIG. 1 is a color chart of an oil before treatment (a) and an oil after treatment (b).

FIG. 2 is a color map (a) of commercial furfural and a color map (b) of recycled furfural produced by the process.

Detailed Description

The invention will be further illustrated by reference to the following examples. The technical solution of the present invention is not limited to the specific embodiments listed below, and includes any combination between the specific embodiments.

Example 1:

the process for reducing the total sulfur and total nitrogen content in the FCC raw oil by the series process is specifically carried out according to the following steps:

(1) mixing an extractant furfural and catalytic cracking feed oil FCC in a volume ratio of 1-5: 1 in a centrifuge tube, placing in a constant-temperature water bath at 30-80 ℃, and keeping for 1-30 minutes.

(2) And (2) fully shaking and mixing the FCC feed oil obtained in the step (1) and a liquid mixture of an extractant furfural, and immediately centrifuging at the rotating speed of 1000-15000 rpm for 1-15 minutes.

(3) Taking out the centrifuge tube, placing the centrifuge tube in a constant-temperature water bath again, and keeping the centrifuge tube for 1-30 minutes. The upper layer of the obtained centrifugal tube is treated oil, and the lower layer of the centrifugal tube is treated by extractant furfural.

(4) Repeating the steps (2) to (3) for 3 times.

(5) Transferring the upper treated oil to a double-neck jacketed bottle, adding a metal-organic framework material type catalyst UiO-66 and 30 wt.% H under magnetic stirring₂O₂The aqueous solution reacts, after the reaction is finished, the oil phase, the water phase and the catalyst phase are centrifugally separated, and the method is characterized in that: the addition amount of the catalyst is 0.1-0.5 g of 30 wt.% H added in every 5mL of oil product₂O₂The addition amount of the water solution is 0.1-5 mL per 5mL of oil product, the reaction time is 0.5-5 h, and the reaction temperature is 30-120 ℃.

(6) And (3) mixing the oil phase obtained by centrifugal separation after the reaction in the step (5) and an extractant furfural in a volume ratio of 1: 1-5 in a centrifugal tube, placing in a constant-temperature water bath at 30-80 ℃, and keeping for 1-30 minutes.

(7) And (4) fully shaking and mixing the treated oil product obtained in the step (6) with a liquid mixture of an extractant furfural, and immediately centrifuging at the rotating speed of 1000-15000 r/min for 1-15 min.

(8) Taking out the centrifuge tube, placing the centrifuge tube in a constant-temperature water bath at the temperature of 30-80 ℃ again, and keeping the temperature for 1-30 minutes.

(9) Repeating the steps (7) to (8) for a plurality of times. The upper layer of the obtained centrifugal tube is treated oil, and the lower layer of the centrifugal tube is treated by extractant furfural.

(10) And (5) collecting the furfural phase obtained after the step (4) and the step (8), placing the furfural phase in a heart-shaped bottle, placing the heart-shaped bottle in a constant-temperature oil bath at the temperature of 100-150 ℃, and performing rotary evaporation for 20-120 minutes under the pressure of-0.1 MPa to obtain the clarified recovered furfural.

(11) And after the process is finished, detecting the total sulfur content and the total nitrogen content of the treated oil product. The results were calculated from the measured data and are shown in Table 1. (Total Sulfur content measuring apparatus: X-ray fluorescence spectrometer Lab-X3500; Total Nitrogen content measuring apparatus: Antek-MultiTek Total Sulfur, Total Nitrogen, halogen Analyzer)

TABLE 1

Example 2:

the process for reducing the total sulfur and the total nitrogen content in FCC feed oil by the series process is specifically carried out according to the following steps:

(1) mixing an extracting agent NMP and FCC feed oil in a volume ratio of 1-5: 1 in a centrifuge tube, and placing the centrifuge tube in a constant-temperature water bath at 30-80 ℃ for 1-30 minutes.

(2) And (2) fully shaking and mixing the liquid mixture of the FCC feed oil obtained in the step (1) and an extracting agent NMP, and immediately centrifuging at the rotating speed of 1000-15000 r/min for 1-15 min.

(3) Taking out the centrifuge tube, placing the centrifuge tube in a constant-temperature water bath at the temperature of 30-80 ℃ again, and keeping the temperature for 1-30 minutes. The upper layer of the obtained centrifugal tube is treated oil, and the lower layer of the obtained centrifugal tube is extracting agent NMP.

(4) Repeating the steps (2) to (3) for 3 times.

(5) Transferring the treated oil product on the upper layer to a double-neck sleeve bottle, and adding a metal oxide catalyst MoO under the condition of magnetic stirring₃And 30 wt.% H₂O₂The aqueous solution reacts, after the reaction is finished, the oil phase, the water phase and the catalyst phase are centrifugally separated, and the method is characterized in that: the addition amount of the catalyst is 0.1-0.5 g of 30 wt.% H added in every 5mL of oil product₂O₂The addition amount of the aqueous solution is 0.1-5 mL per 5mL of oil product, and the reaction time is 0.5 ∞And 5h, wherein the reaction temperature is 30-120 ℃.

(6) And (3) mixing the oil phase obtained by centrifugal separation after the reaction in the step (5) and an extracting agent NMP in a volume ratio of 1: 1-5 in a centrifuge tube, placing in a constant-temperature water bath at 30-80 ℃, and keeping for 1-30 minutes.

(7) And (4) fully shaking and mixing the treated oil product obtained in the step (6) with a liquid mixture of an extracting agent NMP, and immediately centrifuging at the rotating speed of 1000-15000 rpm for 1-15 minutes.

(8) Taking out the centrifuge tube, placing the centrifuge tube in a constant-temperature water bath at the temperature of 30-80 ℃ again, and keeping the temperature for 1-30 minutes.

(9) Repeating the steps (7) to (8) for a plurality of times. The upper layer of the obtained centrifugal tube is treated oil, and the lower layer of the obtained centrifugal tube is extracting agent NMP.

(10) And (5) collecting the NMP phase obtained after the step (4) and the step (8) are finished, placing the NMP phase in a heart-shaped bottle in a constant-temperature oil bath at 140-170 ℃, rotationally evaporating for 30 minutes under-0.1 MPa, and recovering the clear NMP.

(11) And after the process is finished, detecting the total sulfur content of the treated oil product. The results calculated from the measured data are shown in Table 2. (Total Sulfur content measuring apparatus: X-ray fluorescence spectrometer Lab-X3500)

TABLE 2

(1) The FCC feed oil is from catalytic cracking hydrogenation feed of Tianjin Hongkong oil field, is viscous liquid at room temperature, is solidified at low temperature, and has increased temperature and reduced viscosity. The total sulfur and nitrogen contents are shown in Table 3.

TABLE 3

	Total sulfur content	Total nitrogen content
			Catalytic cracking hydrogenation raw material for Tianjin Hongkong oil field	1040ppm	1016ppm

(2) The calculation method is as follows:

(3)