SU954415A1 - Process for purifying solld paraffin - Google Patents

Description

The invention relates to methods for the purification of solid paraffins and may find application in the petroleum refining industry, in particular in the production of solid paraffins.

A known method of purification of paraffins by treating it with 95-98% sulfuric acid or oleum at 6080 C l.

A known method of purification of paraffins, according to which the catalytic purification of raw paraffin is carried out on a pre-sulphurized catalyst at a hydrogen pressure of 40-70 MPa, followed by water-vapor stabilization and purification of hydrogenate with bleaching clays or adsorbents 2.

The disadvantages of this method are the high demands on the quality of the feedstock on the content of oil and aromatic hydrocarbons, as well as the need for careful preparation of paraffin before the hydrotreating process. Tg1K, vacuum distillation of caci is necessary to obtain fractions boiling up to 470s, deep de-oiling of gacha to an oil content in raw paraffin less than 0% by 5% by weight.

A known method of purification of solid paraffins is selective and solvent - ethylene glycol and dimethylformamide. Purification of dimethyl forms: -; the house is carried out at 70-75s with a ratio of raw materials: solvent 1: 0.7 j

However, in a known manner, it is possible to obtain paraffin brand T with an oil content of 2.3% by weight, having a color of KH-51 of 80 mm. The limestone process does not provide highly purified paraffins.

The purpose of the invention is to increase the degree of purification and reduce the oil content in paraffin.

This goal is achieved by the fact that during purification of solid vapor of athena by treating it with dimethylformamide at elevated temperature, treatment with dimethylformamyl is carried out in two stages with EO-XSO C in the first stage and 60-70s in the second stage.

When cleaning, it is desirable to use dimethylformamide with a water content of 0.1-15% by weight.

The method is carried out as follows.

Raw paraffin in the 1st stage is subjected to extraction purification with dimethylformamide (DMF) at 90-130®С and the processing ratio of the raw material with solvent 0.5-2.0tl, contact time 10-30 minutes. At temperatures above 80 ° C, DMF has a dissolving ability with respect to the | Oil components of solid para-Finov, D as a result of the 1st purification stage, the depth of oil recovery from paraffin reaches 75%,

After the i-th stage, the paraffin is directed to the 2nd processing stage, where at a temperature of 60-70 ° C and a solvent multiplicity of 0.5-2.0; 1, the contact time is 10-30 minutes; cleaning to obtain solid paraffinor, having a color higher than 270 mm in KN-5 with glass No. 1 and not containing an1; orogs; nny substances.

With a decrease in temperature, the purification process to 60–70 ° C, the dissipative capacity of daF drops, and the high molecular weight paraffinic hydrocarbons act as anti-solvents, which leads to an increase in the selectivity of the solvent to resinous dyes. As a result, deep bleaching and high stability of solid paraffins is provided at the 2nd stage. The content of the Veda in drgmetilformamide can reach from Ofl to 15 wt.% 0

Regeneration of the solvent from the raffinate solution is carried out by water washing, and from the extract solution - by distillation under vacuum. The application of the above-described technological solution allows the high purity solid paraffins not to contain carcinogenic substances (with a simultaneous decrease in the content of mg. In them by 30-75%, last.) The last service significantly improves the capabilities of the hydrostatic cleaning process, allows vy5) abatyvat from low-grade paraffin samples high-purity paraffins B and P.

Example. The raw paraffin obtained in the process of filtration and thermal de-oiling of the distillate fraction 350-470 ° C with an oil content of 0.5% by weight, melting point 56, and color 50y; m in KN -) 1, is treated with dimethylformamide in two steps "(Ta b l. 1 1,.

Table. one

Continued table. one

Example 2

100 60

25 20

eleven

As a result of the purification, highly purified paraffin is obtained, the characteristics of which are given in Table 2.

EXAMPLE 2 Crude paraffin extracted from a distillate feedstock using selective solvents with an oil content of 1.7 May,%, melting point 56, and color 20 mm, is treated with dimethylformamide under the following conditions.

The result is a highly purified paraffin, the characteristic of which is given in table 2,

Table 2

.56.9 56.5 0.13 0.49

Color ochscheny paraffin on KN-51 mm with glass number 1

Carcinogen Content

Color stability, days

EXAMPLE 3. Oscarbate parain, the quality of which is given in Example 2, is treated with dimethylformamide with a water content of 15% under the same conditions as in Example 2,

As a result of the purification, highly purified paraffin is obtained, having a color of 270 mm with glass No. 1 and containing oils of O 58 May.%

Table 3 presents comparative data on the purification proposed by and from aecTHbEi methods of two types of paraffin

Table 3

Melting point, ° С51

oils

2.24

51

№ 1, 10

The content of can- Prisut-Prisut-Strong Pr.

Substances strong strong

PHONPHONE PHONE

As can be seen from the presented data, the proposed method allows to increase the degree of purification of paraffins, reduce the oil content in them by 30-75% and increase the color stability of products, as well as produce high-purity paraffins of grade B and P from technical brand paraffins, which makes it possible to increase productivity deoiling units by 10-20%.

Claims (3)

1. A method of purifying paraffin wax by treating it with Dimethylformamide at elevated temperature, characterized in that, in order to increase the purification rate and reduce the oil content in para51, 3 56.8 56.8 56.9 0.56 0.70 0.49 0.21 270 70 270 270 OUTSIDE The treatment with dimethylformamide is carried out in two steps at 90-130 ° C in the first stage and 60-7.0c in the second stage. 30 2. Method 1, characterized in that dimethylformamide is used with a water content of 0.1-15% by weight. Information sources, 35 taken into account in the examination 1. Pereverzev A.I. Paraffin production. M., Himi, 1973, p.200 2. Author's certificate of the USSR 40 N 432171, cl. C 10 G 43/02, 1974. 3. Report of the Grozny Oil Research Institute of Solid Paraffins Cleaning Selective Solvents. Grozny, 1978, s about 6 (prototype). 45