RU2573573C1 - Method for obtaining basic components of high-index petroleum oils - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method for obtaining basic components of high-index petroleum oils is realised from non-converted residue of vacuum gasoil hydrocracking, obtained in the process of vacuum distillation of mazuts of sulphurous and highly sulphurous petroleum. Method is characterised by the fact that non-converted residue of hydrocracking is subjected to rectification in order to separate fraction 400-500°C with its further extraction with N-methylpyrrolidone and further separation into extract and raffinate solutions, distillation of N-methylpyrrolidone from rafinate and extract solutions, deparaffinisation of obtained raffinate by binary solvent MEK-toluene and further distillation of solvent from filtrate.

EFFECT: obtaining high-index basic oil with ultralow content of sulphur.

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Description

The invention relates to oil refining processes, in particular to the production of basic components of high index petroleum oils.

The environmental characteristics of petroleum oils, including residual oils, are mainly affected by the sulfur content and group composition of hydrocarbons. The technical characteristics of residual oils are influenced by the viscosity index.

As basic requirements for base oils, Table 1 summarizes the specifications in accordance with the API classification.

A patent for a METHOD FOR PRODUCING BASIC COMPONENTS OF OIL OILS is given as a possible prototype (Patent RU 2109793, publication date: 04/27/1998; applicant: Open Joint-Stock Company "Ufaneftekhim"; authors: Gilyaziev RF, Sitnikov SA, Mingaraev S.S., Khamitov G.G., Gaysin I.Kh., Batyrov N.A.), which recommends a method for producing the basic components of petroleum oils by catalytic hydrocracking of petroleum feedstock to obtain a residual fraction of hydrocracking, vacuum distillation of the latter with isolation of light and heavy fractions, and Solvent dewaxing and after-treatment, characterized in that the control outputs of the light and heavy fractions is carried out by varying the amount of a residual fraction hydrocracking extending recycled to the hydrocracker feedstock in the range 0-60 wt. % on the hydrocracking process feed and the boiling point of the hydrocracking process feed within 480-520 ° C.

The disadvantage of the above examples is the lack of regulation of the group chemical composition of the obtained base oil (table 1).

When creating the invention, the task was to obtain a high-index residual base oil with an ultra low sulfur content and a minimum content of polycyclic aromatic hydrocarbons from an available raw material base that meets the requirements of group II and / or group III according to API classification (table 1).

The above problem is solved by the method of obtaining the basic components of high index petroleum oils from the unconverted residue of fuel oil hydrocracking of vacuum gas oil obtained in the process of vacuum distillation of heavy oil and sour crude oils, in which, according to the invention, the unconverted residue of fuel oil hydrocracking of sulphurous and sour oils is subjected to rectification -500 ° C followed by its extraction with N-methylpyrrolidone and subsequent separation into extract and raff adjusted to room solutions, N-methylpyrrolidone, distillation of the raffinate and the extract solutions, dewaxing the raffinate obtained binary solvent methyl ethyl ketone (MEK) -toluene and followed by distilling off the solvent from the filtrate.

The proposed method due to the use of distillation and subsequent extraction with a selective solvent of the target fraction of the unconverted hydrocracking residue of vacuum gas oil allows to obtain the basic component of high index oil from available raw materials.

The essence of the proposed method is illustrated by the following example.

At the first stage, from the unconverted fuel hydrocracking residue by vacuum distillation on a standard ARN-2 apparatus under laboratory conditions according to GOST 11011-85, a fraction was obtained with boiling intervals of 400-500 ° C (tables 2 and 3).

At the second stage, the obtained fraction of the unconverted hydrocracking residue at boiling intervals of 400-500 ° was subjected to extraction with a selective solvent N-methylpyrrolidone. Extraction was carried out once in a heated separatory funnel with a stirrer and an adjustable thermostat. Mechanical stirring at the temperature of extraction was carried out for 30 minutes at atmospheric pressure. The speed of rotation of the mixer was chosen so that there was effective mixing without the formation of a large funnel and a stable emulsion. The separation of the layers was carried out at a temperature of extraction for 30 minutes in a clean conical heat-resistant flask.

At the third stage, the raffinate solution was washed with distilled water with intensive mechanical stirring without forming an emulsion and a temperature of 60-70 ° until the solvent was completely removed. The amount of water leaching is at least seven. The amount of water per wash is at least one volume of a raffinate solution in a separatory funnel. The removal of washing water with a solvent was carried out by settling in a separatory funnel.

At the fourth stage, the obtained raffinate was filtered through a double desalted paper filter with calcium chloride of the grade “ХЧ” at a temperature of 70 ° C to remove traces of water.

For the obtained raffinate sample, the main physicochemical parameters were determined (table 4) and the material balance of the extraction was compiled (table 5).

The balance of the distillation of the hydrocracking residue is presented in table 3.

Approximate yield of fraction 400 - c.k. is 49% vol.

According to the analysis results in table 4, it is most rational to use a sample obtained with a solvent: raw material ratio of 1.5: 1 and a process temperature of 60 ° C, since its physicochemical quality indicators (raffinate yield, total sulfur content, density, index viscosity, refractive index) are most optimal for subsequent dewaxing.

At the fifth stage, according to the selected optimal technological regime of selective cleaning, a raffinate sample was accumulated to obtain dewaxed oil with a pour point of 15 ° C. The dewaxing was carried out with an MEK-toluene binary solvent under laboratory conditions on a desalted paper filter under vacuum, followed by distillation of the solvent from the obtained filtrate. The technological regime of raffinate dewaxing is presented in table 6.

The material balance of raffinate dewaxing is presented in table 7.

The results of determining the physicochemical properties of the obtained sample of dewaxed oil are presented in table 8.

The obtained dewaxed oil (table 8) fully meets the requirements of the II group of oils according to API classification, namely, the total sulfur content of 0.0011 (≤0.03) and viscosity index 114 (80-119).

The quality parameters of the obtained base components of high-index petroleum oils from the hydrocracking residue are regulated by changing:

- temperature extraction fractions 400-500 ° C N-methylpyrrolidone,

- volume ratio of solvent: raw material in the extraction process.

Monitoring of base oil indicators in accordance with the requirements of GOST and API standard systems.

Thus, when creating this invention, the problem of obtaining the basic components of high-index petroleum oils with an ultra-low sulfur content and a minimum content of polycyclic aromatic hydrocarbons from an available raw material base meeting the requirements of API classification group II (tables 1 and 8) was solved.

Claims (1)

A method of obtaining the basic components of high index petroleum oils from the unconverted residue of fuel oil hydrocracking of vacuum gas oil obtained in the process of vacuum distillation of heavy oil and sour crude oils, characterized in that the unconverted residue of fuel hydrocracking of sulfur and high sulphurous oils is subjected to rectification to select fraction 400-500 ° C its subsequent extraction with N-methylpyrrolidone and subsequent separation into extract and raffinate solutions, distillation of N-methylpyrrod lidone from raffinate and extract solutions, dewaxing the obtained raffinate with MEK-toluene binary solvent and subsequent distillation of the solvent from the filtrate.