CS204934B1 - Process for preparing solid pickling agent - Google Patents

Description

The present invention relates to the preparation of a solid naphthalene-based sulfoacid preparation and its alkyl derivatives.

Leather tanning takes place in a strong acid environment. The pre-treatment is weak alkaline and by sudden transition into an acidic environment while binding the agent, the face contracts, coarsens and tanning is prolonged. Therefore, before the tanning process is carried out, the purpose of which is to acidify the ground. The active component of the modern glycol compositions is an acid, generally sulfuric acid, bound to a suitable carrier. Modern picnics are based on the sulfoacids of naphthalene and its derivatives. The process for the preparation of naphthalene sulfo acids and derivatives thereof has long been known and described in detail in the chemical literature. The final product form is generally a solidified melt of a mixture of naphthalenesulfoacids with sulfuric acid, possibly treated by adding water to a paste, with a substantially blurred pour point that cannot be directly converted into a bulk form, or an aqueous solution of for drying. By neutralization, the sulfoacid loses functional activity for picnicking. Said final forms of the glycol preparations are difficult to handle and imperfect for commercial use.

It has been found that the deficiencies of the final forms of the glycol preparations can be remedied by the preparation of solid forms of the naphthalene-sulfonic acid-based pictogram preparation and one to three sulfo groups per molecule or of the alkylnaphthalene-coated sulfoacids.

204 934

204 934 wherein R is m is n is alkyl

(SO ₃ H) _n to 5 and 1 to 3 according to the invention, characterized in that the sulphonation of the starting material is carried out with sulfuric acid or oleic or chlorosulphonic acid in a molar ratio of 1sl to 2.5, the excess considered as sulfur trioxide being converted by adding equimolar amounts of alkali metal or ammonium and / or magnesium sulphate to the respective hydrogen sulphate are added, from 1 to 35 wt. % of water, based on the sulfoacid mixture content, and the melt thus formed at a temperature of 115 to 160 ° C is converted to a solid free-flowing form.

By converting it into the hydrogen sulphate of the above cations, the mixture is converted into a melt whose freezing point can be varied to some extent by the addition of water. The clear and free-flowing form of the preparation can be achieved by cooling the melt on a cooled flake machine. Advantageously, the melt can be converted to a solid particulate form by pouring into a non-polar liquid having a pour point of not more than 60 ° C with a dynamic viscosity under normal conditions of 5 to 50 mPas and after cooling below the pour point. Suitable non-polar liquids are, for example, kerosene, mineral oils, decahydronaphthalene, tetrachlorethylene.

The process according to the invention makes it possible to prepare very easy-to-fill cropping preparations which allow easier handling, preparation and dosing in the cropping process.

Examples:

Example 1

To 1500 parts mass. naphthalene was added

2065 parts by weight sulfuric acid and sulfonated at 140 ° C for 4 hours. To the sulfonation product was added

526 parts by weight magnesium sulfate,

579 parts by weight of ammonium sulphate and

250 parts by weight water. The product was tempered to 140 ° C and poured onto the cooled surface. Scratching gave a Scale Product.

Example 2

To 1500 parts mass. naphthalene was added

1636 parts by weight sulfuric acid and sulfonated for 1.5 hours at sulfonation was added 650 parts by weight. ammonium sulphate and

250 parts by weight water. The product was tempered to 155 ° C and poured on the flask to obtain a scale product.

160 ° C. Cooled platform to the product. Škrá204 934

Example 3

The naphthalene sulfonation product prepared according to Example 2 was slowly poured with stirring into a ten-fold excess of mineral oil having a viscosity of 7 mPa.s at 50 ° C. The temperature of the medium was maintained at 80 ° C by cooling. The product was isolated by centrifugation and washing with petrol.

A granular product having a particle diameter of 0.5 to 3 mm was obtained.

Example 4

To 1500 parts mass. 2-Methylnaphthalene was added

1500 parts by weight sulfuric acid and sulfonated for 4 hours at 140 ° C. To the sulfonation product was added 600 parts by weight. ammonium sulphate and

250 parts by weight water and a product of 120 ° C were granulated by pouring into tetra-chloroethylene. Cooling lowered the temperature to 90 ° C and separated the product by filtration.

Example 5

To 1500 parts mass. 1300 parts by weight of naphthalene were added. Sulfuric acid and parts by mass. benzene. It was sulfonated for 4 hours at 160 ° C under azeotropic distillation of water with benzene. To the sulfone product was added

180 parts by weight sodium sulphate; and

210 parts by weight water and the product at 130 ° C was granulated by pouring it into kerosene with stirring. Cooling maintained the temperature at 70 ° C. The product was separated from kerosene by filtration.

Example 6

To 1500 parts mass. mixtures of alkynaphthalenes having an average molecular weight of 249, prepared by alkylating a mixture of naphthalene and methylnaphthalenes with butanol in a molar ratio of 1: 2 in the presence of sulfuric acid, are added

1000 parts by weight 20% olea so that the temperature does not exceed 40 °, then heated to 80 ° over hours and sulfonates at that temperature for 1 hour. To the sulfonation product is added

610 parts by weight ammonium sulphate and

270 parts by weight water and the product is granulated according to Example 3.

Example 7

To 1500 parts mass. a mixture of polyisopropylnaphthalenes with small amounts of mono- and dl-isopropylnaphthene of an average molecular weight of 252 is added

700 parts by weight halosulfonic acid and

500 parts by weight of sulfuric acid and sulfonated for 2 hours at 1.5 ° C under development of chloro2O4 934 hydrogen at 90 ° C. 675 parts by weight of sulfonation product are added. ammonium sulphate and

275 parts by weight water and the product is granulated according to Example 3.

Claims (3)

SUBJECT OF THE INVENTION 1. A process for preparing a solid naphthalene-β-sulfonic acid piccolic acid preparation with one to three sulfo groups per molecule or an alkylnaphthalene sulfoacid of the general formula wherein (SO ₃ H) _n m is 1 to 5 and _n is 1 to 3; oleic or halosulfonic acid in a molar ratio of 1: 1 to 2.5, the excess considered as sulfur trioxide is converted by addition of an equimolar amount of alkali metal or ammonium or magnesium sulphate to the corresponding hydrogen sulphate, 1 to 35 wt. % water, based on the sulfoacid mixture content, and the melt thus formed at a temperature of 115-160 ° C and converted to a solid bulk form. 2. Process according to claim 1, characterized in that the melt is converted into a solid loose form by flaking. 3. The method of claim 1, wherein the melt is converted into a solid particulate form by pouring into a non-polar liquid having a pour point of not more than 60 [deg.] 0 with dynamic viscosity under normal conditions of 5 to 50 mPa.s. liquid.