JPH02247286A - Production of high-boiling solvent with high aromatic content - Google Patents

Abstract

PURPOSE:To obtain the subject solvent, having a low mixed aniline point and excellent in solubility at a low production cost by partially recycling a reforming reaction product of a kerosene fraction and simultaneously distilling, separating and recovering a specific fraction from the resultant produced oil. CONSTITUTION:A kerosene fraction or a raffinate obtained after recovering n-paraffines therefrom is subjected to reforming reaction and part of the resultant formed oil is recycled as a raw material for the reforming reaction. A fraction having the boiling point within the range of 185-220 deg.C is simultaneously distilled, separated and recovered to afford the objective solvent having <=21 deg.C mixed aniline point.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing a high boiling point, high aromatic content solvent using a kerosene fraction or a raffinate after recovering normal paraffins from a kerosene fraction. .

[Prior art] A fraction with a boiling point range of 185 to 220°C and mainly consisting of aromatic components is used as a paint solvent and thinner for baking using phenolic resin, alkyd resin, urea resin, melamine resin, acrylic resin, etc. It is used as a cleaning solvent for metal parts, an emulsion for agricultural chemicals, an oil compounding agent for machinery, and a solvent for reaction systems. These solvents are required to have a mixed aniline point of 21° C. or lower from the viewpoint of solubility.

Conventionally, this type of solvent has been recovered from coal tar oil, or by mixing ethylene cracker bottoms with C9 heavy oil (a fraction with a carbon number of 9 or more recovered from reformed oil obtained from a naphtha reforming reaction). It is produced by hydrogenation treatment, alkylation of naphthalene, dinuclearization of monocyclic aromatic compounds, etc. These methods generally have the problem of high manufacturing costs.

By the way, by catalytically reforming kerosene fraction, high boiling point,
It has been reported that a fraction containing highly aromatic components is produced (Journal of the Japan Petroleum Institute, Vol. 13° No. 6 (197
0), P468-474], However, in the reforming reaction of kerosene fraction, 1 having a mixed aniline point of 21°C or less
In order to obtain a fraction of 85 to 220°C, harsh reaction conditions are required, which results in extremely short catalyst life, which poses a problem in industrial production.

Problems to be Solved by the Invention The present invention solves the above-mentioned problems, and an object of the present invention is to produce a highly soluble, low-cost, and highly soluble aniline mixture having a mixed aniline point of 21°C or lower. The object of the present invention is to provide a method for producing a high boiling point, high aromatic content solvent.

[Means for Solving the Problems] The present invention involves reforming a kerosene fraction or a raffinate after recovering normal paraffin from a kerosene fraction, and then reforming the resulting product without distilling or separating it by distillation.
The fraction with a boiling point range of ~220°C is separated by distillation, and a part of it is recycled as a reforming raw material.
It consists of recovering a fraction in the boiling range of 20°C.

The kerosene fraction referred to in the present invention refers to the kerosene fraction obtained by distillation separation operation.
Refers to fractions distilled in a temperature range of 0 to 300°C, including straight-run kerosene fractions obtained by atmospheric distillation of crude oil, as well as thermal cracking, catalytic cracking, etc. of petroleum fractions, residues, etc. It goes without saying that fractions having the above-mentioned boiling point range obtained by hydrogenolysis, alkylation, other purification treatments, etc. can also be used. This kerosene fraction preferably has a sulfur content and a nitrogen content of 50 ppm or less, and this is carried out using a generally employed hydrodesulfurization treatment method under normal desulfurization conditions, such as alumina or silica. On a carrier such as alumina,
cobalt.

Using a catalyst supporting one or more of nickel, molybdenum, tungsten, etc., at a temperature of 250 to 430°C, 10 to
200 kg/cnf pressure, liquid hourly velocity (LH3V)
0.1~i5h-”, hydrogen circulation amount 50=140ON
rr? It is preferable to use desulfurized oil desulfurized under the conditions of /kQ.

In the present invention, in addition to the above-mentioned kerosene fraction, a raffinate obtained by recovering normal paraffin from this kerosene fraction may be used, and in this case, the reforming reaction conditions can be made mild.

This normal paraffin can be removed using an adsorption separation method using zeolite or a separation method using a urea adduct. This Roughine-1 is sufficient if normal paraffin is collected and removed at a recovery rate of about 50 to 95%.

For the reforming reaction, a catalytic reforming method which is widely used as a method for producing high octane gasoline from naphtha fraction etc. can be adopted.

In this case, for example, a catalyst in which platinum is supported using alumina as a carrier, or rhenium, germanium, soot, iridium, ruthenium, etc. in addition to platinum is used.
Temperature of 0 °C, pressure fluid hourly space velocity (LH3V) of 1-50 kg/cl, 0.1-3 h-1, hydrogen/oil molar ratio 0.
It can be carried out under 5 to 20 conditions.

Other modification reaction methods include zeolite or crystalline aluminosilicate, silica, alumina, zirconia, titania, chromia, solid phosphoric acid, or oxides such as indium, lanthanum, manganese, cerium, or tin; , using an acidic refractory containing a mixture of two or more of these, or a catalyst containing or supporting metals such as platinum, palladium, and rhenium, at a temperature of 250 to 700°C, 1 to 100kg/
cid (7) pressure, 0.1~20h"' (7) LHSV
It can also be carried out under conditions where the molar ratio of hydrogen to hydrogenated oil is 00.

Although a reactor in which part of the reforming reaction actor is a fixed bed may be used, a reactor comprising a moving bed to which a continuous catalyst regeneration method is added may also be used.

A part of the oil produced after the reforming reaction obtained in this way is
It is recycled again as a raw material for the reforming reaction. this is,
This is because it has been found that it is industrially extremely difficult to sufficiently lower the mixed aniline point, which is an index of solubility required as an aromatic solvent, through one-through modification.

This recycling may be a part of the total fraction of the produced oil, or a part separated by distillation from the produced oil, but in particular,
It is preferable to partially recycle the fraction in the range of 185 to 220° C. separated by distillation, because the mixed aniline point can be lowered and the yield of the solvent as a product can be increased. The optimal value of this recycling ratio varies depending on the type of raw material oil, reforming conditions, etc., and cannot be determined generally, but it should generally be selected in the range of 20 to 300% by volume based on fresh feed. I can do it.

185-220℃ from the product oil obtained as above.
By distilling and recovering fractions in the range of
Solvents with high aromatic content can be obtained as products.

[Examples] (Examples 1 to 6, Comparative Examples 1 to 2) Using a desulfurized kerosene fraction having the properties shown in Table 1 obtained by hydrodesulfurizing a kerosene fraction and zeolite from this kerosene fraction, normal paraffin was produced. Using raffinate having the properties shown in Table 1, which recovered 90% by weight of /cntG,
Liquid hourly space velocity (L) IsV) 0,8 h-”, hydrogen/
The reforming reaction was carried out under the conditions of an oil molar ratio of 6 and the recycling conditions shown in Table 2. A fraction of 195 to 215° C. was separated by distillation from this produced oil, and its properties are shown in Table 2.

Table 1 From these results, it can be seen that by recycling a portion of the produced oil during the reforming reaction of kerosene fractions, a solvent with a lower mixed aniline point can be obtained compared to the one-through case. .

[Effects of the Invention] The present invention performs a reforming reaction on kerosene fraction and recycles a part of the resulting oil, so it can be produced at low manufacturing cost.
It has the special effect of being able to produce a high-boiling point, highly aromatic-containing solvent with excellent solubility and a mixed aniline point of 21° C. or lower.

Claims (4)

[Claims] (1) A kerosene fraction is subjected to a reforming reaction, and then a part of the resulting product oil is recycled as a raw material for the reforming reaction, and a fraction with a boiling point in the range of 185 to 220°C is separated by distillation from the product oil. A method for producing a high-boiling point, highly aromatic-containing solvent, which comprises recovering the solvent. (2) A kerosene fraction is subjected to a reforming reaction, and then a fraction in the range of 185 to 220°C is distilled and recovered from the resulting product oil, and a part of the fraction is recycled as a raw material for the reforming reaction. A method for producing a high boiling point, high aromatic content solvent. (3) The raffinate after recovering normal paraffin from the kerosene fraction is subjected to a reforming reaction, and then a part of the resulting product oil is recycled as a raw material for the reforming reaction, and the boiling point range of 185 to 220°C is recovered from the product oil. A method for producing a high-boiling point, highly aromatic-containing solvent, which comprises recovering a fraction by distillation. (4) After recovering normal paraffin from the kerosene fraction, the raffinate is subjected to a reforming reaction, and then a fraction in the range of 185 to 220°C is distilled and collected from the resulting product oil, and one of the fractions is A method for producing a high boiling point, high aromatic content solvent, characterized in that part of the solvent is recycled as a raw material for a reforming reaction.