RU2100077C1 - Method of preparing catalyst for liquid-phase oxidation of sulfur compounds - Google Patents

Abstract

FIELD: oxidation catalysts. SUBSTANCE: catalyst is prepared by sulfuration of cobalt tetrachlorophthalocyanine by oleum in presence of boric acid on heating followed by cooling reaction mixture, treating it with oxidant, and isolating target product. According to invention, sodium nitrite is used as oxidant at its weight ratio to cobalt tetrachlorophthalocyanine 1: (0.097-0.584). EFFECT: essentially simplified procedure and reduced consumption of chemicals.

Description

 The invention relates to methods for preparing phthalocyanine catalysts for the oxidative purification of hydrocarbon distillates and diesel fuel from sulfur compounds and can be used in the gas, oil refining, petrochemical, leather, chemical and pulp and paper industries.

Known [1] is a method of preparing a catalyst for the oxidation of sulfur compounds based on disulfonic acid 4,4 ', 4'',4''' - cobalt tetraoxyphthalocyanine. According to this method, cobalt tetrachlorophthalocyanine obtained by fusion of 4-chlorophthalic acid with cobalt chloride and urea is sulfonated with oleum in the presence of boric acid when heated. Then the sulfomass is cooled, copper monochloride is added in an amount of (6 - 70) • 10 ^-3 mol per 1 mol of cobalt tetrachlorophthalocyanine and the chlorine atoms present in cobalt tetrachlorophthalocyanine disulfonic acid are replaced by OH groups by treatment with nitrosylsulfuric acid. The reaction mass is poured onto ice, the separated product is filtered off, washed with water and dried.

 There is also known [2] a method for producing a catalyst for liquid-phase oxidation of sulfur compounds by sulfonation of 4.4 ', 4' ', 4' '' - cobalt tetrachlorophthalocyanine with oleum when heated in the presence of boric acid, followed by cooling of the reaction mixture, its treatment with nitrosyl sulfuric acid, aging and product isolation by diluting the reaction mass with water. Product washing is carried out by decantation. The finished product is filtered off, washed on the filter with water to a neutral wash water medium, dried and ground.

The closest to the invention in technical essence and the achieved result is a method for producing a catalyst for liquid-phase oxidation of sulfur compounds [3] In this method, 4.4 ', 4'',4''' - cobalt tetrachlorophthalocyanine is sulfonated with 10% oleum at 110 115 ^o C in the presence of boric acid, followed by cooling the reaction mass to 20 30 ^o C. Then the sulfomass is treated with an oxidizing agent with a freshly prepared solution of nitrosylsulfuric acid in monohydrate. To obtain a solution of nitrosylsulfuric acid, dry sodium nitrite is dissolved in monohydrate at a temperature of 10 15 ^o C, the reaction mass is heated to 80 85 ^o C, maintained and stirred at this temperature until complete dissolution of sodium nitrite. The resulting solution is cooled to 15 20 ^o C and used for the treatment of sulfomass. In this case, nitrosylsulfuric acid is introduced under the liquid layer at a temperature not exceeding 25 ^° C through the diaphragm pipe, after which the reaction mass is maintained and the desired product is isolated. For isolation, the reaction mass is diluted with water to a residual acidity of 50–70% in terms of sulfuric acid, incubated for 0.5–1.5 hours, and the reaction mass is treated with a 2% solution of sodium chloride, followed by exposure until the precipitated product is completely precipitated. The upper clarified wash water layer is drained, and the lower layer of the catalyst suspension is washed with water until the residual acidity of the wash water is no more than 3%. The washed catalyst suspension is filtered off, dried and ground.

The disadvantages of this method are:
the complexity of the process, due, firstly, to the need to use a freshly prepared nitrosylsulfuric acid solution in the catalyst synthesis process and, secondly, to the exact observance of the conditions for introducing nitrosylsulfuric acid into the reaction mass (under a liquid layer through a diaphragm pipe, cooling). If these conditions are not met, the composition of the resulting catalytic complex changes with the formation of products insoluble in an aqueous alkaline medium;
a sufficiently long duration of the production method up to 36 40 h;
the use in the synthesis of large quantities of monohydrate 4 m ³ per 1 ton of product.

 The inventive task was to create a method for producing a catalyst for liquid-phase oxidation of sulfur compounds, which, with a significant simplification of the technology, would provide a reduction in the duration of the process and the consumption of reagents.

 The essence of the invention lies in the fact that in the method of preparing a catalyst for liquid-phase oxidation of sulfur compounds by sulfonation of cobalt tetrachlorophthalocyanine with oleum in the presence of boric acid when heating, cooling the reaction mass, treating it with an oxidizing agent and isolating the target product, sodium nitrite is used as an oxidizing agent in a mass ratio of tetrachlorophthalocyanine cobalt sodium nitrite, equal to 1 (0.097 0.584).

 The increase in the ratio of cobalt tetrachlorophthalocyanine sodium nitrite leads to a decrease in the yield of the target product. In addition, the product is poorly sedimented, slowly filtered.

 The decrease in the ratio is impractical due to the low stability of the target product in the process of desulfurization of hydrocarbons (stability constant drops 2.5 3 times).

The invention has several advantages, as it allows to simplify the technology and reduce the duration of obtaining the target product due to:
eliminating the stage of preparation of nitrosylsulfuric acid;
exclusion of the stage of preparation of monohydrate and 10% oleum;
reducing the duration of the process of obtaining the target product from 36 40 hours to 23 25 hours;
30% reduction in oleum consumption
In addition, the invention allows to simplify the hardware design of the process, since the apparatus for the preparation of nitrosylsulfuric acid and the pipe-diaphragm for loading it into a sulfurator are excluded.

 Distinctive features of the invention are the use of sodium nitrite as an oxidizing agent and the mass ratio of cobalt tetrachlorophthalocyanine sodium nitrite equal to 1 (0.097 0.584).

To implement the method, the following substances are used:
1.4.4 ', 4'',4''' - cobalt tetrachlorophthalocyanine. Despite the long-known popularity of this compound, its industrial production as a commercial product is still not in Russia. It is produced only as an intermediate in the production of the Ivkaz catalyst (TU 6-14-06-107-90) or as an intermediate from the monosodium salt of 4-chlorophthalic acid (TU 6-14-699-82);
2. Boric acid GOST 18704-78;
3. Oleum, 19% GOST 2184-77, technical;
4. Sodium nitrite GOST 19906-74E;
5. Salt "Extra" GOST 13830-91
The method is implemented as follows. Cobalt tetrachlorophthalocyanine is dissolved with stirring in oleum, boric acid is added, heated, sulfated. The sulfomass is cooled and dry sodium nitrite is added to it with stirring, the extract is made, and then the target product is isolated by known methods (reprecipitation on ice or chilled water, washing the precipitate by decantation, filtration, drying, grinding).

Example 1. 60.0 l of a 19% oleum is loaded into an apparatus with an anchor mixer, the mixer is turned on, and the oleum is cooled to 20 ^° C by starting up the water in the apparatus jacket. Then, with the ejection turned on, they load 7.09 kg (0.01 mol) in small portions. ) cobalt tetrachlorophthalocyanine and 1.3 kg (0.021 mol) of boric acid. The reaction mass is heated to 113 ^o C by steam release in the jacket of the apparatus and kept at this temperature and stirring for 1.5 hours. At the end of the exposure, the sulfomass is cooled to 20 ^o C and, with the ejection switched on and stirring, 2.28 kg (0.033) are loaded in small portions. mol) sodium nitrite. During loading, the temperature rises to 30 35 ^o C. After loading the sodium nitrite, the reaction mass is kept for 2 hours with stirring and the reaction mass is diluted with water to a residual acidity of 50% in terms of sulfuric acid. Then incubated for 1 h, poured a 5% solution of sodium chloride (to a total volume of 1 m ³ ), stirred and sediment until complete precipitation. The settled clarified liquid layer is drained by decantation, and the catalyst suspension is washed with water until a residual acidity of not more than 1% is filtered off, dried and ground.

Yield: 8.02 kg of a technical product with a basic substance content of 68.9%
Example 2. The method is carried out analogously to example 1, but to oxidize the reaction mass after sulfonation and cooling load 0.69 kg (0.01 mol) of sodium nitrite.

Yield: 7.95 kg of technical product with a basic substance content of 70.2%
Example 3. The method is carried out analogously to example 1, but 4.14 kg (0.06 mol) of sodium nitrite are charged for oxidation.

 Yield: 7.65 kg of a technical product with a basic substance content of 68-93%

Claims (1)

 A method of preparing a catalyst for liquid-phase oxidation of sulfur compounds by sulfonation of cobalt tetrachlorophthalocyanine with oleum in the presence of boric acid when heating, cooling the reaction mixture, treating it with an oxidizing agent and isolating the target product, characterized in that sodium nitrite is used as an oxidizing agent in a weight ratio of cobalt tetrachlorophthalocyanine sodium nitrite 1 0.097 0.584.