SU1143457A1 - Method of extracting cobalt,manganese and nickel from ash of dimethylterephthalate production - Google Patents

Abstract

COBALT EXTRACTION METHOD, MAVTAHUA AND NICKEL FROM ASH PGOIZVODSTVA daMETILTEREFTALATA, vklyuchayupday processing ash acetic kislo.tsh at elevated temperature, separation of metals from solutions of salts of the residual ash, characterized in that, in order povyshoshsh the degree of purity, and of reducing their noTCf simplify method the ash is first treated with an aqueous alkaline agent solution at a mass ratio of the alkaline agent and metals in the ash

Description

4ib 00 1st SP

The invention relates to cobalt, manganese, and nickel recovery methods, which are catalyst components, from dimethyl terephthalate production ash. A method is known for extracting cobalt from ashes containing cobalt, manganese, iron, copper and other compounds, according to which the ash is first treated by heating with nitric acid until the metals are completely converted into solution, which is then treated with potassium permanganate to convert manganese into insoluble manganese dioxide and is separated the last of the solution. Then the pH of the solution is adjusted to about 6.5 with ammonia and the impurities of zhles and copper are separated from the cobalt nitrate solution. By adding oxalic acid to the solution, a precipitate of cobalt oxalate is obtained, which is separated from the flj solution. The disadvantage of this method is that it requires a large number of operations. In addition, it requires considerable time and consumption of auxiliary substances to obtain cobalt oxalate. There is also known a method for extracting cobalt from ash after burning waste from the production of aromatic dicarboxylic acids, according to which ash containing cobalt, margane and nickel is first treated with water to remove water-soluble impurities from it, and then with a strong mineral acid to convert the metals into solution. Hydrobromic or hydrobromic acid is added to the resulting solution to convert the manganese to an insoluble form. Subsequently adjusting the pH of the solution to a value of 2.5-7 with alkaline reagent, iron is precipitated and, after filtration, a solution of the inorganic cobalt salt is obtained. From the solution, cobalt is precipitated, for example, in the form of carbonate by adding an alkali metal carbonate to the solution, and the cobalt carbonate is separated from the solution by filtration 12}. The disadvantages of the method are the need for a large number of operations for the extraction of cobalt from the sludge and its purification, as well as that it takes considerable time and consumption of various reagents. In addition, significant metal losses are unavoidable during cleaning, and manganese, which is a constituent part of the oxidation catalyst, is irreversibly lost in the sol. Cobalt recovered from the ash is obtained in a catalytically inactive form (in the form of an inorganic salt), which makes it difficult to use it as an oxidation catalyst. The closest to the invention, according to the technical essence and the achieved result 7J, is the method of extracting cobalt, manganese and nickel from the ash of dimethyl terephthalate production, which consists in treating the ash with aqueous solutions of acetic acid or formic acid (or their mixture) at 60-90 ° C in 1-2 hours, followed by separation of the solution of acetates or metal formates from residual ash. The degree of extraction of metals (in the form of acetates) is 75-80%. A disadvantage of the known method is the low degree of purity of the regenerated catalyst, affecting its catalytic activity and selectivity, as compared with the fresh catalyst. Therefore, the pereHaiHiped catalyst needs additional purification, which will inevitably cause a complication of the process and a loss of metals. The purpose of the invention is to increase the purity of metals, reduce their losses and simplify the process. This goal is achieved in that, according to the method for extracting cobalt, Martanian and nickel from the ashes of dimethyl terephthalate production, consisting in treating the ashes with an aqueous solution of an alkaline agent at a mass ratio of alkaline agent and metals in the ash (0.08-1.03) :, and then with water and glacial acetic acid or its aqueous solution at a mass ratio of acetic acid and metals in the ash (3-21): 1 at elevated temperature, followed by separation of metal salts from residual ash. Alkaline agents passivating the surface of metal oxides and the slurry after alkaline treatment can be washed with water to remove all water-soluble impurities without loss of the catalyst component metals with wash water. Without alkaline treatment, the losses of metals are very large (for example, up to 7.0% for cobalt), and water soluble impurities are not completely removed. As alkaline agents, for example, caustic soda or carbonate is used. Washing the ash with water is carried out in order to remove from it water-soluble impurities (mainly alkali and alkaline earth metal compounds) that inhibit the oxidation process. In addition, treatment of the sludge with water allows for an increase in the yield of acetates of cobalt, manganese, and nickel, with its subsequent processing with acetic acid. After washing the ash with water, it is treated with glacial acetic acid Kli with its aqueous solution at a mass ratio of acetic acid and metals in the ash (3-21): 1

and the treatment is carried out at elevated temperature. The proposed method allows cobalt, manganese and nickel to be recovered from the ash in the form of a mixture of acetates of these metals after treating the ash with acetic acid or its aqueous solutions.

solutions at elevated temperatures. The resultant solution can be used as a starting catalyst for the oxidation process.

The proposed method makes it possible to extract metals by 84.2%, while there is no loss of metals with flushing with 1 water. The degree of purity of the metals increases due to the complete removal of iron ions and other heavy impurities.

Example 1. In a flask with a capacity of 250 ml equipped with a reflux condenser, load 3 g of ash from the production of dimethyl terephthalate, containing wt.%

Co52,67

Mp3.76

Ni0.38

Fe0.50

Water3.30

Soot6,40 Associated oxygen (in oxides), impurities of alkaline earth metal compounds, etc. The rest and the mixture consisting of 0.135 g of caustic soda and 100 g of Bojcvbi.

While stirring, the mixture is held for 1 hour and 20 ° C, then the washings are separated from the ash, which is washed with 200 ml of distilled water. 100 g of glacial acetic acid at TeMnepatype and the solvent are then boiled, the ash is cooled, and the reaction mixture is separated from the solid phase. The second filtrate is a solution of cobalt acetates, Maprataia and nickel in acetic acid. The composition of the regenerated catalyst is given in the table.

Example 2. The ash is processed as in Process 1 using a mixture of 3 g of KgCOe and too ml of water for washing.

Example 3. The treatment of the ash is carried out as in Example 2, using g of 10% acetic acid to dissolve the oxides.

Example 4. Processing ash production of dimethyl terephthalate, containing wt.%: With -52,19

MP3.59

Fe0.52

conducted as. in example 1, using for washing a mixture consisting of 1.35 g of caustic

soda and 100 ml of water, and to dissolve the oxides in the sol, a mixture of 25 g of acetic acid and 100 ml of water.

Example 5. The treatment of the ash composition of Example 4 was carried out as in Example 1, using a mixture consisting of 1.72 g of sodium hydroxide and 100 ml of water for washing, and a mixture consisting of 35 g of acetic acid and 90 ml of water.

Example 6 The treatment of the ash composition of Example 4 is carried out as in Example 1, using a mixture of 0.3 g of sodium hydroxide in 50 ml of water for washing the ash, and a mixture of 5 g of acetic acid and 95 ml of water.

Example 7 (for comparison). The treatment of the ashes of the composition indicated in example 1 was carried out as in example 1, using 100 ml of water to wash the ashes.

Example 8 (for comparison). The treatment of the ash composition of Example 4 was carried out as in Example 1, without washing with water, and a mixture of 5 g of acetic acid and .95 ml of water was used for dissolving.

Example 9 (for comparison). The treatment of the ashes of composition 1 by example 4 is carried out as in example 1, using 100 ml of water for washing, and a mixture of 5 g of acetic acid and 95 ml of water for washing.

Example 10. In a bubbling column with a porous bottom with a capacity of 250 ml a water separator, a reflux cooler, a contact thermometer and electrical heating is placed 150 ml of p-xylene, 0.3 g of p-toluic acid and .3 ml of the regenerated catalyst obtained according to example 8. The mixture is heated up to 115 ° C in a stream of nitrogen and, upon reaching it, air is passed for 120 minutes at a rate of 100 l / h. Upon completion of the oxidation, the acid number of the oxide of ha is 61.9 mg KOH / 1 g. The amount of carbon dioxide released is 1.77-10 g per unit acid value.

Example 11. Oxidation of 150 ml of n-KOtlol was carried out as in Example 10, using 3 ml of regenerated catalysis for oxidation. of the lysator obtained in Example 9. The acid number of the oxidate was 58.4 mg KOH / 1 g, the amount of carbon dioxide leached was 1.6210 g per unit. acid number.

Example 12. Oxidation of 150 ml of p-xylene was carried out as in Example 10, ° using 3 ml of the regenerated katat obtained in Example 6 for oxidation. The acid number of the oxidate was 64.0 mg KOH / 1 g, the amount

emitted carbon dioxide 1,6010g per unit. acid number.

Example 13. Oxidation of 150 ml of p-xnolol is carried out as in Example 10, using for oxidizing 3 ml of a solution of pure cobalt acetate in pure 5% aqueous acetic acid containing 10 g / l of cobalt. The acid number of the oxidate is 66.1, the amount of carbon dioxide released is 1.5610 CO per unit acid number.

Thus, the proposed method allows to significantly simplify the process by reducing the number of operations and their duration. The method can be carried out on a typical

chemical equipment. The proposed method also makes it possible to significantly reduce the loss of catalyst component metals with the complete removal of all other water-soluble impurities; remove from the resulting solution the acetates of the catalyst metal components of other heavy metals, for example iron; use the resulting solution directly in the oxidation process

without release of metals. I

These advantages generally enhance the regeneration of the oxidation catalyst.

1061.0

, 9512,313,4

100

0.8

100 100 1.0 0.9 125

14.9

3.2 125 21.0 3.2

100

4.4

3.0

4.7 100

1.0

12.0 100

4.1

3.0 100

; .4,4

behind

Table continuation

Claims (1)

METHOD FOR RELEASING COBALT, MANHANZE AND NICKEL FROM ASH OF PRODUCTION OF DIMETHYL TEREPHALATE, including treating ash with acetic acid at elevated temperature, separating metal salt solutions from residual ash, characterized in that, with a chain for increasing the purity of metals, reducing their loss and simplifying the method , the ash is first treated with an aqueous solution of an alkaline agent at a mass ratio of alkaline agent and metals in the ash (0.08-1.03): 1, and then with water and glacial acetic acid, or its aqueous solution, in a mass ratio ii acetic acid and metals in the ash (3-21): 1.