CN111826217B - A kind of low carbon number, light color, sulfur-free, chlorine-free and ash-free polymerization inhibitor and its application - Google Patents

Abstract

The invention relates to a medium material required in the petrochemical production process, in particular to a low-carbon light-color sulfur-free chlorine-free ashless polymerization inhibitor and application thereof. According to the fact that the mixed oil (hereinafter referred to as light mixed oil) of gasoline and diesel oil is distilled and separated, a low-carbon light-color sulfur-free chlorine-free ashless polymerization inhibitor is compounded, the use safety performance of the low-carbon light-color sulfur-free chlorine-free ashless polymerization inhibitor is evaluated, technical guarantee is provided for long-period safe operation of a distillation device, and the method is applicable to distillation and separation of the light mixed oil under the conditions of normal pressure and the temperature of less than or equal to 250 ℃; the method can prevent olefin in oil products, olefin, oxygen and various oil product additives in the oil products in the distillation process, and condensation coking of iron ions, manganese ions and the like generated by equipment corrosion and/or separated by the additives in the distillation separation process by adding diphenylamine derivatives, p-phenylenediamine derivatives, alkyl succinimide and carbon nonaromatic hydrocarbon, and reduce scaling coke-forming substances.

Description

A kind of low carbon number, light color, sulfur-free, chlorine-free and ash-free polymerization inhibitor and its application

technical field

The invention relates to a medium material required in a petrochemical production process, more particularly, the invention relates to a low-carbon number, light-colored, sulfur-free, chlorine-free, ash-free polymerization inhibitor and its application.

Background technique

The pipeline transportation technology has been widely used in the long-distance transportation of gasoline and diesel products for automobiles at home and abroad, but there are not many reports on the mixed oil treatment technology in the pipeline transportation technology. There are five main methods: direct back-mixing method; distillation separation method; Metal oxide treatment method; alkali treatment method; filtration method. Among them, the distillation separation method is the most used and the most effective. However, in the distillation separation method, the olefins in the oil are easily condensed and fouled with the olefins in the oil, various additives, and iron ions, manganese ions, etc. in the distillation process when heated, resulting in high oil color. There are many problems such as high colloid content and short start-up cycle.

In order to reduce the condensation, scaling and coke formation of oil products during transportation, storage and use, it may be considered to add detergent and dispersant, polymerization inhibitor, anti-thermal oxidation stabilizer, etc. However, most of these additives are only suitable for normal temperature processes, and it is very rare that they can be safely used in high temperature heating processes, and there are very few related reports.

According to the fact that the mixed oil (hereinafter referred to as light mixed oil) arising from the pipeline transportation of gasoline and diesel oil needs to be separated by distillation, the actual situation of gasoline and diesel oil can be recovered, and a low-carbon number suitable for the distillation and separation process of light mixed oil is compounded. Light-colored sulfur-free and ashless polymerization inhibitor, which can prevent olefins in oil and olefins in oil, oxygen and various oil additives in the distillation process, as well as equipment corrosion in the process of separation from distillation and/or by The condensation and coking of iron ions, manganese ions, etc., which are separated from the additives, can reduce the scaling and coking substances, and can also prevent the occurrence of problems affecting the quality of the oil such as large chromaticity and high colloidal content, thereby ensuring the safe long-term operation of the distillation unit. Distilled oil products meet the requirements of national quality indicators.

SUMMARY OF THE INVENTION

In order to solve the above problems, the first aspect of the present invention provides a low carbon number, light color, sulfur-free, chlorine-free and ashless polymerization inhibitor. The components of the polymerization inhibitor include carbon element, hydrogen element, oxygen element and nitrogen element.

As a preferred technical solution of the present invention, the raw materials for the preparation of the polymerization inhibitor include diphenylamine derivatives, p-phenylenediamine derivatives, succinimide and carbon nonarene.

As a preferred technical solution of the present invention, the raw materials for the preparation of the polymerization inhibitor include, in parts by weight, 5-25 parts of diphenylamine derivatives, 25-40 parts of p-phenylenediamine derivatives, and 7-20 parts of butanediol. imide and 20 to 35 parts of carbon nine aromatics.

As a preferred technical solution of the present invention, the substituent of the diphenylamine derivative is selected from one or more of hydroxyl, alkyl, alkoxy, and amino.

As a preferred technical solution of the present invention, the total number of carbon elements of the diphenylamine derivative is less than or equal to 14.

As a preferred technical solution of the present invention, the structural formula of the p-phenylenediamine derivative is shown in formula (1):

R ₁ is selected from one or both of normal and/or iso-alkane groups; R ₂ is selected from one or both of normal and/or iso-alkane groups.

As a preferred technical solution of the present invention, the total number of carbon elements of the p-phenylenediamine derivative is less than or equal to 14.

As a preferred technical solution of the present invention, the succinimide is N-hydrocarbyl succinimide.

As a preferred technical solution of the present invention, the hydrocarbon group in the N-hydrocarbylsuccinimide is selected from one or more of methyl, ethyl, propyl, isobutyl, and n-butyl.

The second aspect of the present invention provides an application of the described low-carbon number, light-colored, sulfur-free, chlorine-free, and ashless polymerization inhibitor for the high-temperature distillation and separation process of light mixed oil.

Compared with the prior art, the present invention has the following beneficial effects:

(1) the present invention is based on the practice of distillation and separation of the mixed oil of gasoline and diesel oil (hereinafter referred to as light mixed oil), compound a kind of low carbon number light color sulfur-free ashless polymerization inhibitor, and carry out low carbon number light color without The safety performance evaluation of sulfur ashless polymerization inhibitor provides technical guarantee for the long-term safe operation of the distillation unit, and can be applied to the distillation and separation of light mixed oil under the condition of normal pressure and ≤250℃.

(2) By adding diphenylamine derivatives, p-phenylenediamine derivatives, succinimide and C9 aromatic hydrocarbons, this patent can prevent the olefins in the oil and the olefins, oxygen and various oils in the oil during the distillation process. Product additives, and condensation coking with iron ions, manganese ions, etc., which are produced by equipment corrosion during distillation and separation and/or separated from additives, to reduce fouling coke-producing substances.

(3) In addition, the diphenylamine derivatives provided by the invention can also prevent the generation of the problems affecting the quality such as the large chromaticity of the oil and the high colloid content, thereby ensuring that the safe long-term operation of the distillation unit and the distilled oil meet the national quality index requirements .

(4) When the polymerization inhibitor provided by the present invention is used for distillation and separation, it can ensure that the unwashed colloid of gasoline is ≯ 30mg/100ml, the colloid after washing is ≯ 5mg/100ml, and the chromaticity is less than 1; the oxidation stability of diesel oil (total insoluble material)≯2.5mg/100ml, chroma <3, and does not affect the boiling range and sulfur content of gasoline and diesel oil.

(5) In addition, all substances in the polymerization inhibitor provided by the present invention are less toxic, and a little proper protection during use can ensure personal health and safety during production and use.

(6) The preparation raw materials used in the present invention are all colorless or light yellow, and after compounding, it is a very light yellow liquid mixture, and the color is lighter than gasoline and diesel, and does not affect the chromaticity of gasoline and diesel.

Description of drawings

Figure 1 shows the device for the distillation and separation of light mixed oil in the laboratory.

Detailed ways

The content of the present invention may be more readily understood by reference to the following detailed description of preferred embodiments of the invention and the included examples. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the definitions in this specification will control.

As used herein, the term "prepared from" is synonymous with "comprising". As used herein, the terms "comprising," "including," "having," "containing," or any other variation thereof, are intended to cover non-exclusive inclusion. For example, a composition, step, method, article or device comprising the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such composition, step, method, article or device elements.

The conjunction "consisting of" excludes any unspecified element, step or component. If used in a claim, this phrase would make the claim closed to the exclusion of materials other than those described, but with the exception of conventional impurities associated therewith. When the phrase "consisting of" appears in a clause in the body of a claim rather than immediately following the subject matter, it is limited only to the elements described in that clause; other elements are not excluded from the claim as a whole beyond the requirements.

When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or a range bounded by a series of upper preferred values and lower preferred values, this should be understood as specifically disclosing any upper range limit or preferred value and any lower range limit or all ranges formed by any pairing of preferred values, whether or not the ranges are individually disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be construed to include the ranges "1 to 4," "1 to 3," "1 to 2," "1 to 2, and 4 to 5." , "1 to 3 and 5", etc. When numerical ranges are described herein, unless stated otherwise, the ranges are intended to include the endpoints and all integers and fractions within the range.

The singular form includes the plural object of discussion unless the context clearly dictates otherwise. "Optional" or "either" means that the subsequently described item or event may or may not occur, and that the description includes instances where the event occurs and instances where it does not.

Approximate terms in the specification and claims are used to modify a quantity, indicating that the invention is not limited to the specific quantity, but also includes acceptable amendments close to the quantity without causing a change in the relevant basic function. Accordingly, modification of a numerical value with "about", "about", etc. means that the invention is not limited to the precise numerical value. In some instances, the term of approximation may correspond to the precision of the instrument measuring the value. In the present specification and claims, range definitions may be combined and/or interchanged, and unless otherwise stated, these ranges include all subranges subsumed therebetween.

Furthermore, the indefinite articles "a" and "an" preceding an element or component of the invention are not limiting on the quantitative requirement (ie, the number of occurrences) of the element or component. Thus "a" or "an" should be read to include one or at least one, and elements or components in the singular also include the plural unless the number is clearly intended to be in the singular.

The present invention is described below through specific embodiments, but is not limited to the specific examples given below.

By controlling the composition of the polymerization inhibitor to be mainly composed of carbon, oxygen, hydrogen and nitrogen, the applicant controls the polymerization inhibitor to burn up without ash during the use of gasoline or diesel, so as to avoid environmental pollution. The first aspect of the present invention provides a low carbon number, light color, sulfur-free, chlorine-free and ashless polymerization inhibitor, and the components of the polymerization inhibitor include carbon element, hydrogen element, oxygen element and nitrogen element; further, the present invention The composition of the polymerization inhibitor does not include sulfur element and chlorine element. By controlling the polymerization inhibitor without adding elements such as sulfur and chlorine, the applicant can avoid the increase in the content of sulfur and chlorine in gasoline and diesel fuel obtained by distillation, and at the same time, avoid damage to devices, such as gasoline engine parts, during use. .

In one embodiment, the raw materials for the preparation of the polymerization inhibitor include diphenylamine derivatives, p-phenylenediamine derivatives, succinimide and carbon nonarene.

In one embodiment, the raw materials for the preparation of the polymerization inhibitor include, in parts by weight, 5-25 parts of diphenylamine derivatives, 25-40 parts of p-phenylenediamine derivatives, and 7-20 parts of succinimide. And 20 to 35 parts of aromatics.

Diphenylamine Derivatives

In one embodiment, the substituent of the diphenylamine derivative of the present invention is selected from one or more of hydroxyl, alkyl, alkoxy, and amino.

Examples of diphenylamine derivatives whose substituents are hydroxyl groups include, but are not limited to, 4,4'-dihydroxydiphenylamine and 4-hydroxydiphenylamine.

Examples of diphenylamine derivatives whose substituents are hydroxyl and alkyl include, but are not limited to, 4-methyl-3'-hydroxydiphenylamine, 2,6-dimethyl-3'-hydroxydiphenylamine, 2- Methyl-3'-hydroxydiphenylamine.

Examples of diphenylamine derivatives whose substituents are alkyl groups include, but are not limited to, 4,4'-dimethyldiphenylamine, 4-methyldiphenylamine.

Examples of diphenylamine derivatives whose substituents are alkoxy groups include, but are not limited to, 4-methoxydiphenylamine, 4-ethoxydiphenylamine, and 4,4'-dimethoxydiphenylamine.

Examples of diphenylamine derivatives whose substituents are amino groups include, but are not limited to, 4,4'-diaminodiphenylamine.

The applicant found that by using diphenylamine derivatives containing amine-type functional groups, when the obtained polymerization inhibitor is used in the high-temperature distillation process, it can capture free radicals, interrupt the chain reaction and the gel-forming process, and prevent the color from deepening. Extend the induction period of oil products, etc., and the applicant unexpectedly found that when using diphenylamine derivatives containing hydroxyl groups, compared with hindered phenols or diphenylamines, the polymerization inhibitors containing phenolamine groups can be given or given by protons. The effect of electrons destroys the free radical chain reaction, and the synergistic circulation in the molecule can occur, which further reduces the phenomenon of polycondensation, raw rubber and coke of oil products. Preferably, the substituents of the diphenylamine derivatives of the present invention include hydroxyl groups; further, the total number of carbon elements of the diphenylamine derivatives of the present invention is less than or equal to 14; further, the substituents of the diphenylamine derivatives of the present invention is hydroxyl. Moreover, the applicant found that the diphenylamine of the combination type of phenol and amine not only has good oxidation resistance, but also has high thermal stability.

p-phenylenediamine derivatives

The applicant found that by adding p-phenylenediamine derivatives and diphenylamine derivatives together, the termination of the free radical chain reaction is further promoted, thereby reducing the initiation and catalysis of unstable components (such as olefins, etc.) in gasoline in oxygen and metals Under the action of free radical chain reaction, especially when an oxidation accelerator is added to diesel oil (in order to increase the cetane number), a chain reaction occurs, which significantly reduces the formation of colloid, and the addition of terephthalic acid to the polymerization inhibitor Amine derivatives and diphenylamine derivatives also have the catalytic effect of passivating metals on the oxidation of gasoline and diesel. In one embodiment, the structural formula of the p-phenylenediamine derivative of the present invention is shown in formula (1):

R ₁ is selected from one or both of normal and/or iso-alkane groups; R ₂ is selected from one or both of normal and/or iso-alkane groups.

Examples of alkyl groups include, but are not limited to, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl.

The applicant found that the use of aromatic secondary amines, such as phenylenediamine derivatives, has a better effect than aniline, which may be because the oxidation of phenylenediamine derivatives can generate quinoid structures, and the conjugation of quinoid structures The chain has a strong free radical trapping ability and can trap more molecules of free radicals. Preferably, R ₁ is an alkyl group, and R ₂ is an alkyl group; further, the total number of carbon elements of the p-phenylenediamine derivative is less than or equal to 14; further, the total number of carbon elements of the p-phenylenediamine derivative is less than or equal to 12; further Typically, both R ₁ and R ₂ are n-butyl and/or isobutyl. In addition, by controlling the total carbon number of R ₁ and R ₂ , the side chain of the aromatic ring structure is controlled to be short and not easy to break, avoiding the boiling point range of 159-288 ° C, no thermal cracking, no colloid formation, and no increase in distillation residue. The carbon number of each raw material of the residual carbon polymerization inhibitor, and by controlling the total number of carbon atoms, the boiling point can be just within the distillation range of gasoline and diesel, so that p-phenylenediamine derivatives and diphenylamine derivatives all enter gasoline and diesel during the distillation process. In the product, no waste is generated.

Succinimide

In one embodiment, the succinimide of the present invention is N-hydrocarbylsuccinimide.

Preferably, the hydrocarbon group in the N-hydrocarbylsuccinimide of the present invention is selected from one or more of methyl, ethyl, propyl, isobutyl, and n-butyl; further, the present invention The hydrocarbon group in the N-hydrocarbyl succinimide is methyl.

N-methylsuccinimide can be purchased directly. It is a small molecular weight non-polymer ashless dispersant with excellent low temperature dispersibility and good high temperature stability, which can effectively prevent olefins in oil from forming sludge, paint on separation element packing and/or trays Deposition of films and carbon deposits. Examples of N-methylsuccinimide include, but are not limited to, N-methylsuccinimide from Nanjing Kangmanlin Chemical Industry Co., Ltd.

C9Aromatics

The applicant found that by adding carbon 9 aromatic hydrocarbons , because the structure of the benzene ring in the aromatic hydrocarbons is conducive to promoting the dissolution of other components of the polymerization inhibitor, as well as the uniform dispersion in gasoline, diesel oil, etc., carbon 9 is a polymerization mixture, which is a petroleum light The fraction containing nine carbon atoms aromatic hydrocarbons in the by-product after catalytic reforming, the present invention does not specifically limit the carbon nine aromatic hydrocarbons, which can be enumerated as mesitylene, mesitylene, mesitylene, 1,2-dimethylbenzene In the process of distillation and separation, these aromatics such as base-3-ethylbenzene and propylbenzene can all enter the gasoline component (the content of aromatics in gasoline produced in China still has a large margin and will not exceed the standard), thereby increasing the octane number of gasoline. The present invention does not specifically limit the purchasers of C9 aromatics . In one embodiment, the aromatics described in the present invention are C9 aromatics components separated by a catalytic reformer in an oil refinery. Examples include Maoming Petrochemical Co., Ltd. C9 aromatics obtained from the second set of catalytic reforming units.

Among various hydrocarbons, if the number of carbon atoms is the same, the octane number of n-paraffins is much lower than that of isoparaffins, and the octane number of naphthenes is lower than that of aromatic hydrocarbons. The main components of straight-run gasoline are n-paraffins, isoparaffins and naphthenes. One of the purposes of catalytic reforming is to convert n-paraffins, isoparaffins and The atoms in the naphthene trader are rearranged into isoparaffins and aromatic hydrocarbons with similar or equal molecular weights, thereby obtaining gasoline with high octane number and various aromatic hydrocarbons.

The applicant found that when using a hydroxyl-containing diphenylamine derivative and a p-phenylenediamine derivative with a certain total number of carbon atoms, it is beneficial to improve the thermal stability of these two substances and promote the effect in the high-temperature distillation process, but for Diphenylamine derivatives and p-phenylenediamine derivatives containing a benzene ring have obvious volatilization before the boiling point, so that the ability of these two substances to inhibit free radical reactions cannot be fully exerted. The applicant found that by adding hydrocarbyl succinyl Imines, such as N-methylsuccinimide, interact with the amino groups, hydroxyl groups, and side chain alkyl groups of diphenylamine derivatives and p-phenylenediamine derivatives, which can reduce volatilization. And the applicant unexpectedly found that the traditional polyolefin-based butadiene amide has good detergency and dispersibility in high-boiling lubricating oil due to its large molecular weight and high boiling point, but when used in light fuel oil, it increases colloidal and Residual carbon; while N-methylsuccinimide has a small molecular weight and a short hydrocarbon chain, in addition to good oil cleaning and dispersibility, its methyl group is not easily decomposed or broken by heat, which can promote the various properties of the polymerization inhibitor. It can improve the stability of raw materials, reduce the generation of decomposition, etc., and has a good effect on improving the oxidation stability of oil products, reducing raw rubber and coke, and improving chromaticity.

The present invention does not specifically limit the preparation method of the polymerization inhibitor, which can be prepared by a mixing method.

The second aspect of the present invention provides an application of the above-mentioned low-carbon number, light-colored, sulfur-free, chlorine-free, and ashless polymerization inhibitor for the high-temperature distillation and separation process of light mixed oil.

The light mixed oil of the present invention is a mixture of gasoline and diesel. The high-temperature distillation of the present invention is the distillation and separation of light mixed oil under the condition of normal pressure and ≤250°C.

Example

The present invention will be specifically described below by means of examples. It is necessary to point out here that the following examples are only used to further illustrate the present invention, and should not be construed as limiting the scope of protection of the present invention, and some non-essential improvements made by those skilled in the art according to the above-mentioned content of the present invention and adjustment, still belong to the protection scope of the present invention.

Example 1

This example provides a polymerization inhibitor. The preparation raw materials of the polymerization inhibitor include, in parts by weight, 15 parts of diphenylamine derivatives, 30 parts of p-phenylenediamine derivatives, 15 parts of succinimide and 30 parts of carbon Nine aromatic hydrocarbons; the diphenylamine derivative is 4-hydroxydiphenylamine, and the succinimide is N-methylsuccinimide;

The structural formula of the p-phenylenediamine derivative is shown in formula (1):

Both R ₁ and R ₂ are sec-butyl groups.

The N-methylsuccinimide was purchased from Nanjing Kangmanlin Chemical Industry Co., Ltd.

This example also provides the above-mentioned preparation method of the polymerization inhibitor, which includes the following steps: mixing the preparation raw materials of the polymerization inhibitor to obtain the polymerization inhibitor.

Example 2

This example provides a polymerization inhibitor. The preparation raw materials of the polymerization inhibitor include, in parts by weight, 25 parts of diphenylamine derivatives, 40 parts of p-phenylenediamine derivatives, 20 parts of succinimide and 35 parts of carbon Nine aromatic hydrocarbons; the diphenylamine derivative is 4-hydroxydiphenylamine, and the succinimide is N-ethylsuccinimide;

The structural formula of the p-phenylenediamine derivative is shown in formula (1):

Both R ₁ and R ₂ are sec-butyl groups.

The N-ethylsuccinimide was purchased from Nanjing Kangmanlin Chemical Industry Co., Ltd.

This example also provides the above-mentioned preparation method of the polymerization inhibitor, which includes the following steps: mixing the preparation raw materials of the polymerization inhibitor to obtain the polymerization inhibitor.

Example 3

This example provides a polymerization inhibitor, and the preparation raw materials of the polymerization inhibitor include, in parts by weight, 5 parts of diphenylamine derivatives, 25 parts of p-phenylenediamine derivatives, 7 parts of succinimide and 20 parts of carbon Nine aromatic hydrocarbons ; the diphenylamine derivative is 4-hydroxydiphenylamine, and the succinimide is N-methylsuccinimide;

The structural formula of the p-phenylenediamine derivative is shown in formula (1):

Both R ₁ and R ₂ are sec-butyl groups.

The N-methylsuccinimide was purchased from Nanjing Kangmanlin Chemical Industry Co., Ltd.

This example also provides the above-mentioned preparation method of the polymerization inhibitor, which includes the following steps: mixing the preparation raw materials of the polymerization inhibitor to obtain the polymerization inhibitor.

Example 4

This example provides a polymerization inhibitor. The preparation raw materials of the polymerization inhibitor include, in parts by weight, 15 parts of diphenylamine derivatives, 30 parts of p-phenylenediamine derivatives, 15 parts of succinimide and 30 parts of carbon Nine aromatic hydrocarbons; the diphenylamine derivative is 4-isopropoxydiphenylamine, and the succinimide is N-methylsuccinimide;

The structural formula of the p-phenylenediamine derivative is shown in formula (1):

Both R ₁ and R ₂ are sec-butyl groups.

The N-methylsuccinimide was purchased from Nanjing Kangmanlin Chemical Industry Co., Ltd.

This example also provides the above-mentioned preparation method of the polymerization inhibitor, which includes the following steps: mixing the preparation raw materials of the polymerization inhibitor to obtain the polymerization inhibitor.

Example 5

This example provides a polymerization inhibitor. The preparation raw materials of the polymerization inhibitor include, in parts by weight, 15 parts of diphenylamine derivatives, 30 parts of p-phenylenediamine derivatives, 15 parts of succinimide and 30 parts of carbon Nine aromatic hydrocarbons; the diphenylamine derivative is 4-hydroxydiphenylamine, and the succinimide is N-methylsuccinimide;

The structural formula of the p-phenylenediamine derivative is shown in formula (1):

Both R ₁ and R ₂ are heptyl.

The N-methylsuccinimide was purchased from Nanjing Kangmanlin Chemical Industry Co., Ltd.

This example also provides the above-mentioned preparation method of the polymerization inhibitor, which includes the following steps: mixing the preparation raw materials of the polymerization inhibitor to obtain the polymerization inhibitor.

Example 6

This example provides a polymerization inhibitor. The preparation raw materials of the polymerization inhibitor include, in parts by weight, 15 parts of diphenylamine derivatives, 30 parts of p-phenylenediamine derivatives, 15 parts of succinimide and 30 parts of carbon Nine aromatic hydrocarbons; the diphenylamine derivative is 4-hydroxydiphenylamine, and the succinimide is N-methylsuccinimide;

The structural formula of the p-phenylenediamine derivative is shown in formula (1):

Both R ₁ and R ₂ are methyl groups.

The N-methylsuccinimide was purchased from Nanjing Kangmanlin Chemical Industry Co., Ltd.

This example also provides the above-mentioned preparation method of the polymerization inhibitor, which includes the following steps: mixing the preparation raw materials of the polymerization inhibitor to obtain the polymerization inhibitor.

Example 7

This example provides a polymerization inhibitor. The preparation raw materials of the polymerization inhibitor include, in parts by weight, 15 parts of diphenylamine derivatives, 30 parts of p-phenylenediamine derivatives, 15 parts of succinimide and 30 parts of carbon Nine aromatic hydrocarbons; the diphenylamine derivative is 4-hydroxydiphenylamine, and the succinimide is N-methylsuccinimide;

The structural formula of the p-phenylenediamine derivative is shown in formula (1):

Both R ₁ and R ₂ are phenyl.

The N-methylsuccinimide was purchased from Nanjing Kangmanlin Chemical Industry Co., Ltd.

This example also provides the above-mentioned preparation method of the polymerization inhibitor, which includes the following steps: mixing the preparation raw materials of the polymerization inhibitor to obtain the polymerization inhibitor.

Example 8

This example provides a polymerization inhibitor. The preparation raw materials of the polymerization inhibitor include, in parts by weight, 15 parts of diphenylamine derivatives, 30 parts of p-phenylenediamine derivatives, 15 parts of succinimide and 30 parts of carbon Nine aromatic hydrocarbons; the diphenylamine derivative is 4-hydroxydiphenylamine, and the succinimide is polyisobutylene succinimide;

The structural formula of the p-phenylenediamine derivative is shown in formula (1):

Both R ₁ and R ₂ are sec-butyl groups.

The polyisobutylene succinimide was purchased from T154 of Shenyang Juxin Tiancheng Chemical Co., Ltd.

This example also provides the above-mentioned preparation method of the polymerization inhibitor, which includes the following steps: mixing the preparation raw materials of the polymerization inhibitor to obtain the polymerization inhibitor.

Performance evaluation

The following experiments were carried out with the examples provided as experimental groups.

1. Laboratory polymerization inhibition test: Referring to Figure 1, firstly, a rapid distillation apparatus similar to the principle of an industrial distillation device is used to carry out the polymerization inhibitor addition amount of the light mixed oil relative to gasoline and diesel when the amount is 0ppm, 100ppm, and 200ppm respectively. Test (atmospheric pressure distillation, distillation pot temperature 240-250 ° C, distillation column top temperature 185-195 ° C, intermittent operation, heating distillation time 120-135 minutes), using the polymerization inhibitor provided in Example 1, the evaluation The quality of gasoline and diesel oil obtained by distillation, the test data are shown in Table 1 and Table 2.

Table 1 Gasoline Oil Analysis Items

Table 2 Diesel Oil Analysis Items

From Table 1, Table 2 data analysis of rapid distillation of light mixed oil, the oxidative stability (in terms of total insolubles), 10% distillation residue carbon residue, unwashed gum content, The content and color number of solvent-washed gums are all better than those without polymerization inhibitor. Therefore, adding a polymerization inhibitor to prevent raw rubber from forming coke is one of the simple and effective methods.

2. Industrialized polymerization inhibition test: add 200 ppm polymerization inhibitor from the feed inlet of the industrial distillation tower or from the reflux inlet at the top of the tower, and carry out the test of different addition amounts of the polymerization inhibitor for the light mixed oil (atmospheric pressure distillation, distillation tower column The top pressure is 0.02MPa, the feed temperature of the distillation column is 98-125 °C, the bottom temperature of the distillation column is 240-245 °C, and the top temperature of the distillation column is 165-172 °C, continuous distillation operation), wherein the polymerization inhibitor provided in Example 1 is used. The quality of gasoline and diesel oil obtained by distillation was evaluated. The test data are shown in Table 3 and Table 4.

Table 3 Performance index of diesel fuel before and after injection of polymerization inhibitor

Table 4 Performance indexes of gasoline from the unit before and after injection of polymerization inhibitor

From the data in Table 3 and Table 4, it can be seen that adding the polymerization inhibitor provided by the present invention can significantly improve the chromaticity after high-temperature rectification, the content of colloids, oxidation stability, steam residue and carbon residue and other properties.

3. Research on the stability of the polymerization inhibitor: the 200 ppm polymerization inhibitor provided in the example was tested at 200°C according to the laboratory polymerization inhibition test to test the 10% residual carbon c1 of the diesel oil in the light mixed oil, and the same as that of Example 1. Compare the residual carbon c0, calculate the increase rate of carbon residual compared to Example 1 = (c1-c0)/c0 × 100%, and make statistics, where the increase rate of the first level of carbon residual is less than or equal to 5%, and the second level is the residual carbon. The carbon increase rate is greater than 5%, less than or equal to 10%, the 3rd grade is the residual carbon increase rate of more than 10%, less than or equal to 20%, the 4th grade is the residual carbon increase rate of more than 20%, less than or equal to 30%, the 5th grade is more than 30% , and the results are shown in Table 5.

Table 5 Performance Characterization Test

Example Residual carbon increase rate 2 Level 1 3 Level 1 4 level 4 5 Level 5 6 Level 3 7 Level 5 8 Level 5

4. Physical and chemical properties: Part of the physical and chemical properties of the polymerization inhibitor provided in Example 1 were tested, and the results are shown in Table 6.

Table 6 Physical and chemical properties

The technical scheme of the invention is scientific and reasonable, can be safely applied to industrial distillation devices, and effectively reduces olefin and olefin, oxygen, various oil additives in oil products, and iron produced by equipment corrosion in the distillation and separation process and/or segregated by additives The condensation coking of ions, manganese ions, etc., reduces the scaling and coking substances, and ensures that the oil quality indicators meet the national standards. In addition, the present application uses substances with low carbon numbers as raw materials, which can reduce thermal cracking in the boiling point range of 159-288 ° C, does not form colloids, does not increase the residual carbon in the distillation residue, and transfers all of them during the light mixed oil distillation and separation process. Into gasoline or diesel finished products, no waste emissions. Due to the invention of the polymerization inhibitor and relying on the mature distillation technology, the quality problems and long-term operation problems caused by condensation and coking of oil products during the distillation and separation of light mixed oil can be solved, so as to obtain good economic and social benefits.

The foregoing examples are illustrative only and serve to explain some of the features of the methods described herein. The appended claims are intended to claim the broadest conceivable scope and the embodiments presented herein are merely illustrative of selected implementations according to a combination of all possible embodiments. Accordingly, it is the applicant's intention that the appended claims not be limited by the selection of examples that characterize the invention. Some numerical ranges used in the claims also include sub-ranges within them, and variations within these ranges should also be construed, where possible, to be covered by the appended claims.

Claims (4)

1. the application of a low-carbon number light-colored, sulfur-free, chlorine-free, and ash-free polymerization inhibitor, is characterized in that, for the high-temperature distillation separation process of light mixed oil, the composition of described polymerization inhibitor comprises carbon element, hydrogen element, Oxygen and nitrogen; The preparation raw materials of the polymerization inhibitor include, in parts by weight, 5-25 parts of diphenylamine derivatives, 25-40 parts of p-phenylenediamine derivatives, 7-20 parts of succinimide and 20-35 parts of aromatic hydrocarbons; The substituents of the diphenylamine derivatives are selected from hydroxyl groups; the total number of carbon elements of the diphenylamine derivatives are all less than or equal to 14; The succinimide is N-hydrocarbyl succinimide. 2. The application of the low-carbon, light-colored, sulfur-free, chlorine-free, and ashless polymerization inhibitor according to claim 1, wherein the structural formula of the p-phenylenediamine derivative is shown in formula (1):

(1) R ₁ is selected from one or both of normal or isoalkane groups; R ₂ is selected from one or both of normal or isoalkane groups. 3 . The application of the low-carbon, light-colored, sulfur-free, chlorine-free, and ashless polymerization inhibitor according to claim 2 , wherein the total number of carbon elements of the p-phenylenediamine derivative is less than or equal to 14. 4 . 4. the application of low-carbon number light-colored sulfur-free chlorine-free ashless polymerization inhibitor according to claim 1, is characterized in that, the hydrocarbon group in described N-hydrocarbyl succinimide is selected from methyl, ethyl One or more of , propyl, isobutyl, n-butyl.

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