A METHOD OF CARBONIZATE PURIFICATION

Abstract

A method of purification of carbonizate resulting from the thermal recycling process of rubber waste consists in that the carbonizate is mixed with sodium bicarbonate, then deionized water having increased temperature and strong mineral acid and/or mixture of mineral acids are introduced into the obtained mixture, and next the whole is stirred at increased temperature, and filtered at decreased pressure while washing with deionized water having increased temperature, the filtrate is discarded, the solution of a strong base is introduced into the solid residue, and the whole is stirred at increased temperature, then the obtained suspension is filtered at decreased pressure, and washed with deionized water having increased temperature, and next the filtrate is discarded, and the solid residue is dried.

Claims

1. A method of purification of carbonizate resulting from the thermal recycling process of rubber waste, characterized in that the carbonizate is mixed with sodium bicarbonate, then deionized water having increased temperature and strong mineral acid and/or mixture of mineral acids are introduced into the obtained mixture, and next the whole is stirred at increased temperature, and filtered at decreased pressure while washing with deionized water having increased temperature, the filtrate is discarded, the solution of a strong base is introduced into the solid residue, and the whole is stirred at increased temperature, then the obtained suspension is filtered at decreased pressure, and washed with deionized water having increased temperature, and next the filtrate is discarded, and the solid residue is dried.

2. The method according to claim 1, characterized in that the mixing of carbonizate with sodium bicarbonate is carried out wet or dry.

3. The method according to claim 2, characterized in that the mixing of carbonizate with sodium bicarbonate is carried from 10 to 100 mm.

4. The method according to claim 1 characterized in that the hydrochloric acid or sulphuric (IV) acid and/or hydrofluoric acid and/or their mixture is used.

5. The method according to claim 1, characterized in that the granulation of the carbonizate is from 0.02 to 0.3 mm.

6. The method according to claim 1, characterized in that the mass ratio of sodium bicarbonate to carbonizate is from 0.3 to 1.5.

7. The method according to claim 1, characterized in that the mass ratio of hydrochloric acid to raw carbonizate is from 0.5 to 2.0.

8. The method according to claim 1, characterized in that the concentration of hydrochloric acid in the reaction mixture is from 2 to 10%.

9. The method according to claim 1, characterized in that the mass ratio of sulphuric (IV) acid to carbonizate is from 2 to 10.

10. The method according to claim 1, characterized in that the concentration of sulphuric (IV) acid in the reaction mixture is from 13 to 40%.

11. The method according to claim 1, characterized in that the mass ratio of hydrofluoric acid to carbonizate is from 1 to 5.

12. The method according to claim 1, characterized in that the concentration of hydrofluoric acid in the reaction mixture is from 7 to 20%.

13. The method according to claim 1, characterized in that the strong base used is sodium hydroxide, ammonia water and/or their mixture.

14. The method according to claim 1, characterized in that the mass ratio of sodium hydroxide to carbonizate is from 5 to 15.

15. The method according to claim 1, characterized in that the concentration of sodium hydroxide in the etching solution is from 30 to 50%.

16. The method according to claim 1, characterized in that the mass ratio of ammonia to raw carbonizate is from 0.5 to 2.

17. The method according to claim 1, characterized in that the concentration of ammonia in the etching solution is from 1 to 25%.

18. The method according to claim 1, characterized in that the temperature of mixing the carbonizate with the acid solution and/or mixture of acids solution is from 70 to 95° C.

19. The method according to claim 1, characterized in that the time of stirring the mixture of carbonizate with sodium bicarbonate with the solution of acid and/or mixture of mineral acids and with the solution of base and/or mixture of bases is from 15 to 90 min.

20. The method according to claim 1, characterized in that the solid residue is dried at the temperature from 90 to 120° C.

Description

EXAMPLES

[0030] The following examples illustrates the invention.

Example 1

[0031] 4 g of raw carbonizate having ash content of 18% and granulation ≤0.063 mm is dry mixed with 2.67 g of sodium bicarbonate in a ball mill at vibration frequency 30 rpm during 60 min. 5 g of the obtained mixture is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of deionized water having temperature 90° C. and 7.5 cm.sup.3 of hydrochloric acid having concentration 36.5%. The whole is stirred mechanically while maintaining temperature 90° C. for 60 min. Then the suspension is filtered under decreased pressure. The solid residue is washed with 1 dm.sup.3 of deionized water having temperature 90° C. The filtrate is discarded, and the solid residue is transferred to the reaction vessel, into which 50 cm.sup.3 of aqueous solution of sodium hydroxide having concentration of 40% is introduced. The whole is stirred mechanically while maintaining temperature 90° C. for 60 min. Then the suspension is filtered under decreased pressure. The filtrate is discarded, and the solid residue is washed with 1.5 dm.sup.3 of deionized water having temperature 90° C., and then it is dried in a chamber dryer at the temperature 105° C. for 24 h. Carbon product is obtained having decreased ash content of 1.3%.

Example 2

[0032] 4 g of raw carbonizate having ash content of 18% and granulation ≤0.063 mm is dry mixed with 2.67 g of sodium bicarbonate in a ball mill at vibration frequency 30 rpm during 60 min. 5 g of the obtained mixture is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of deionized water having temperature 90° C. and 7.5 cm.sup.3 of hydrochloric acid having concentration 36.5%. The whole is stirred mechanically while maintaining temperature 90° C. for 30 min. Then the suspension is filtered under decreased pressure. The solid residue is washed with 0.5 dm.sup.3 of deionized water having temperature 90° C. The filtrate is discarded, and the solid residue is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of deionized water having temperature 90° C. and 5 cm.sup.3 of sulphuric (IV) acid having concentration 95%. The whole is stirred mechanically while maintaining temperature 90° C. for 30 min. Then the suspension is filtered under decreased pressure. The solid residue is washed with 1 dm.sup.3 of deionized water having temperature 90° C. The filtrate is discarded, and the solid residue is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of aqueous solution of sodium hydroxide having concentration of 40% and 10 cm.sup.3 of ammonia water having concentration of 25%. The whole is stirred mechanically while maintaining temperature 90° C. for 30 min. Then the suspension is filtered under decreased pressure, the filtrate is discarded, and the solid residue is washed with 1.5 dm.sup.3 of deionized water having temperature 90° C., and then it is dried in a chamber dryer at the temperature 105° C. for 24 h. Carbon product is obtained having decreased ash content of 1.6%.

Example 3

[0033] 4 g of raw carbonizate having ash content of 18% and granulation ≤0.063 mm is dry mixed with 2.67 g of sodium bicarbonate in a ball mill at vibration frequency 30 rpm during 60 min. 5 g of the obtained mixture is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of deionized water having temperature 90° C. and 7.5 cm.sup.3 of hydrochloric acid having concentration 36.5%. The whole is stirred mechanically while maintaining temperature 90° C. for 30 min. Then the suspension is filtered under decreased pressure. The solid residue is washed with 1 dm.sup.3 of deionized water having temperature 90° C. The filtrate is discarded, and the solid residue is transferred to the reaction vessel, into which 20 cm.sup.3 of aqueous solution of ammonia water having concentration of 25% is introduced. The whole is stirred mechanically while maintaining temperature 90° C. for 30 min. The suspension is filtered under decreased pressure, the filtrate is discarded, and the solid residue is washed with 1.5 dm.sup.3 of deionized water having temperature 90° C., and then it is dried in a chamber dryer at the temperature 105° C. for 24 h. Carbon product is obtained having decreased ash content of 12.9%.

Example 4

[0034] 4 g of raw carbonizate having ash content of 18% and granulation ≤0.063 mm is dry mixed with 2.67 g of sodium bicarbonate in a ball mill at vibration frequency 30 rpm during 60 min. 5 g of the obtained mixture is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of deionized water having temperature 90° C. and 7.5 cm.sup.3 of hydrochloric acid having concentration 36.5%. After 10 minutes 3 cm.sup.3 of hydrofluoric acid having concentration 40% is introduced. The whole is stirred mechanically while maintaining temperature 90° C. for 20 min. After this time, 9 cm.sup.3 of hydrochloric acid having concentration 36.5% is introduced portion by portion, and the whole is stirred for next 30 min. Then the suspension is filtered under decreased pressure. The solid residue is washed with 1 dm.sup.3 of deionized water having temperature 90° C. The filtrate is discarded, and the solid residue is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of aqueous solution of sodium hydroxide having concentration of 40%. The whole is stirred mechanically while maintaining temperature 90° C. for 30 min. The suspension is filtered under decreased pressure, the filtrate is discarded, and the solid residue is washed with 1.5 dm.sup.3 of deionized water having temperature 90° C., and then it is dried in a chamber dryer at the temperature 105° C. for 24 h. Carbon product is obtained having decreased ash content of 1.3%.

Example 5

[0035] 4 g of raw carbonizate having ash content of 18% and granulation ≤0.063 mm is dry mixed with 2.67 g of sodium bicarbonate in a ball mill at vibration frequency 30 rpm during 60 min. 5 g of the obtained mixture is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of deionized water having temperature 90° C. and 7.5 cm.sup.3 of hydrochloric acid having concentration 36.5%. The whole is stirred mechanically while maintaining temperature 90° C. for 20 min. After this time, at intervals of 20 minutes, two portions of 2 cm.sup.3 each of hydrochloric acid having concentration 36.5% are introduced. Then the suspension is filtered under decreased pressure. The solid residue is washed with 1 dm.sup.3 of deionized water having temperature 90° C. The filtrate is discarded, and the solid residue is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of aqueous solution of sodium hydroxide having concentration of 40%. The whole is stirred mechanically while maintaining temperature 90° C. for 60 min. The suspension is filtered under decreased pressure, the filtrate is discarded, and the solid residue is washed with 1.5 dm.sup.3 of deionized water having temperature 90° C., and then it is dried in a chamber dryer at the temperature 105° C. for 24 h. Carbon product is obtained having decreased ash content of 0.8%.

Example 6

[0036] 4 g of raw carbonizate having ash content of 18% and granulation ≤0.063 mm is dry mixed with 2.67 g of sodium bicarbonate in a ball mill at vibration frequency 30 rpm during 60 min. 5 g of the obtained mixture is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of deionized water having temperature 90° C. and 7.5 cm.sup.3 of hydrochloric acid having concentration 36.5%. The whole is stirred in the water-bath maintaining temperature 90° C. for 30 min. Then the suspension is filtered under decreased pressure. The solid residue is washed with 0.5 dm.sup.3 of deionized water having temperature 90° C. The filtrate is discarded, and the solid residue is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of deionized water having temperature 90° C. and 5 cm.sup.3 of hydrosulphuric acid having concentration 95%. The whole is stirred mechanically while maintaining temperature 90° C. for 15 min. Then the suspension is filtered under decreased pressure. The solid residue is washed with 1 dm.sup.3 of deionized water having temperature 90° C. The filtrate is discarded, and the solid residue is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of aqueous solution of sodium hydroxide having concentration of 40% and 10 cm.sup.3 of ammonia water having concentration of 25%. The whole is stirred mechanically while maintaining temperature 90° C. for 15 min. The suspension is filtered under decreased pressure, the filtrate is discarded, and the solid residue is washed with 1.5 dm.sup.3 of deionized water having temperature 90° C., and then it is dried in a chamber dryer at the temperature 105° C. for 24 h. Carbon product is obtained having decreased ash content of 0.9%.

Example 7

[0037] 4 g of raw carbonizate having ash content of 18% and granulation ≤0.063 mm is dry mixed with 2.67 g of sodium bicarbonate in a ball mill at vibration frequency 30 rpm during 60 min. 5 g of the obtained mixture is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of deionized water having temperature 90° C. and 7.5 cm.sup.3 of hydrochloric acid having concentration 36.5%. The whole is stirred mechanically while maintaining temperature 90° C. for 20 min. After this time 10 cm.sup.3 of sulphuric (IV) acid having concentration 95% is introduced into the mixture, and the whole is stirred for next 20 min. After this time 10 cm.sup.3 of hydrofluoric acid having concentration 70% is introduced into the mixture, and the whole is stirred for next 20 min. Then the suspension is filtered under decreased pressure. The solid residue is washed with 1 dm.sup.3 of deionized water having temperature 90° C. The filtrate is discarded, and the solid residue is transferred to the reaction vessel, into which it is introduced 50 cm.sup.3 of aqueous solution of sodium hydroxide having concentration of 40%. The whole is stirred mechanically while maintaining temperature 90° C. for 60 min. The suspension is filtered under decreased pressure, the filtrate is discarded, and the solid residue is washed with 1.5 dm.sup.3 of deionized water having temperature 90° C., and then it is dried in a chamber dryer at the temperature 105° C. for 24 h. Carbon product is obtained having decreased ash content of 1.6%.