RU2729268C1 - Method of producing modified active coal - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: invention relates to a method of producing modified active coal, which can be used for water treatment of process wastes of chemical and pharmaceutical industries. Method involves washing industrial active coal with distilled water, treatment with potassium permanganate solution with mass fraction of dissolved substance of 10 % at ratio of weight of coal (g) to volume of solution of potassium permanganate (cm³) – 1:10 for 4 hours, low-concentration production effluent treatment ε-caprolactam containing ε-caprolactam to 0.5 g/dm³ and ammonium sulphate to 0.2 g/dm³ at ratio of weight of coal (g) to volume of waste water (cm³) – 1:100 for 24 hours, and heating at temperature 200 °C for 1 hour in air.

EFFECT: invention provides higher sorption capacity of active coal by dimethylamine.

1 cl, 4 tbl, 4 ex

Description

The invention relates to the field of adsorption technology and can be used to obtain modified activated carbons (MAU), used for water treatment of technological effluents of chemical and pharmaceutical industries.

A known method for producing MAU, including impregnating coals with water or a solution of hydrochloric acid with a concentration of 1-4 wt. % when the ratio of the total pore volume of coal and water or acid is 1.0 - (0.7-1.0), and then coal is treated with a 9 ÷ 15% solution of thermoactive resin in furfural with a weight ratio of coal and solution of 1.0 - (0.35 -0.68), holding to flowability and heat treatment with a temperature rise rate of 450-900 deg / h to 700-900 ° C, followed by holding at this temperature for 0.2-0.5 h (RF patent No. 2175885).

The disadvantage of this method is the use of a modifying reagent with a complex composition, as well as the duration and laboriousness of the modification process.

The closest is the method of obtaining MAU, including the treatment with a low-concentrated effluent from the production of ε-caprolactam containing ε-caprolactam up to 0.5 g / dm ³ and ammonium sulfate up to 0.2 g / dm ³ at the ratio of the mass of coal (g) to the volume of waste water (cm ³ ) -1: 10 for 24 hours and further heating at a temperature of 100 ° C for 1 hour in air, characterized in that the AC is treated with a solution of hydrogen peroxide with a mass fraction of a solute of 3% at a ratio of coal mass (g) to the volume of hydrogen peroxide solution (cm ³ ) - 1:10. (RF patent No. 2696447).

The disadvantage of this modification method is the significant consumption of reagents, heat and electricity, as well as the explosive properties of hydrogen peroxide.

The objective of the present invention is to increase the sorption capacity of active carbons for dimethylamine, to reduce the consumption of electricity, reagents, increase the consumption of wastewater, and eliminate explosive reagents.

The task is achieved by washing industrial activated carbon (AC) with distilled water, further processing with a solution of potassium permanganate with a mass fraction of a dissolved substance of 10% at a ratio of the mass of coal (g) to the volume of potassium permanganate solution (cm ³ ) - 1:10 for 4 hours and low-concentrated effluent from the production of ε-caprolactam containing ε-caprolactam up to 0.5 g / dm ³ and ammonium sulfate up to 0.2 g / dm ³ at a ratio of coal mass (g) to waste water volume (cm ³ ) -1: 100 in within 24 hours, as well as further heating at a temperature of 200 ° C in air for 1 hour.

Industrial active carbon of the AG-5 grade was used as a comparison.

Example 1.

AC was washed with distilled water, then treated with a solution of potassium permanganate with a mass fraction of a solute of 10% at a ratio of the mass of coal (g) to the volume of a solution of potassium permanganate (cm ³ ) -1: 10 for 4 hours and a low-concentrated effluent of ε-caprolactam production containing ε-caprolactam up to 0.5 g / dm ³ and ammonium sulfate up to 0.2 g / dm ³ at the ratio of the mass of coal (g) to the volume of wastewater (cm ³ ) - 1: 100 for 24 hours, and also warmed up at temperature 200 ° С for 30 minutes, 1, 2, 3 hours in air.

Then, the modified samples were used for adsorption under static conditions from aqueous solutions of dimethylamine with a concentration of 2 mol / dm ³ . The data obtained are presented in table 1.

Example 2.

AC was washed with distilled water, then treated with a solution of potassium permanganate with a mass fraction of a solute of 10% at a ratio of the mass of coal (g) to the volume of a solution of potassium permanganate (cm ³ ) -1: 10 for 4 hours and a low-concentrated effluent from the production of ε-caprolactam containing ε-caprolactam up to 0.5 g / dm ³ and ammonium sulfate up to 0.2 g / dm ³ at the ratio of the mass of coal (g) to the volume of wastewater (cm ³ ) - 1: 100 for 24 hours, and also warmed up in temperature range: 50, 100, 200, 300 ° С for 1 hour in air.

Then, the modified samples were used for adsorption under static conditions from aqueous solutions of dimethylamine with a concentration of 2 mol / dm ³ . The data obtained are presented in table 2.

Example 3.

AC was washed with distilled water, then treated with a solution of potassium permanganate with a mass fraction of a solute: 0-blank experiment, 5, 10, 15, 20, 30% with the ratio of the mass of coal (g) to the volume of potassium permanganate solution (cm ³ ) - 1: 10 for 4 hours and a low-concentrated effluent from the production of ε-caprolactam containing ε-caprolactam up to 0.5 g / dm ³ and ammonium sulfate up to 0.2 g / dm ³ with the ratio of coal mass (g) to wastewater volume (cm ³ ) -1: 100 for 24 hours, and also warmed up at a temperature of 200 ° C for 1 hour in air.

Then, on the modified samples, adsorption was carried out under static conditions from aqueous solutions of dimethylamine with a concentration of 2 mol / dm ³ . The data obtained are presented in table 3.

Example 4.

AC was washed with distilled water, then treated with a solution of potassium permanganate with a mass fraction of a solute of 10% at a ratio of the mass of coal (g) to the volume of potassium permanganate solution (cm ³ ) - 1:10 for 30 minutes 1, 2, 3, 4, 5 , 10 hours and low-concentrated effluent of ε-caprolactam production, containing ε-caprolactam up to 0.5 g / dm ³ and ammonium sulfate up to 0.2 g / dm ³ with the ratio of coal mass (g) to waste water volume (cm ³ ) - 1: 100 for 24 hours, and also warmed up at a temperature of 200 ° C for 1 hour in air.

Then, on the modified samples, adsorption was carried out under static conditions from aqueous solutions of dimethylamine with a concentration of 2 mol / dm ³ . The data obtained are presented in table 4.

As a result of the studies, the following modification conditions were selected: washing of industrial activated carbon (AC) with distilled water, treatment with a solution of potassium permanganate with a mass fraction of a dissolved substance of 10%, with a ratio of the mass of coal (g) to the volume of hydrogen peroxide solution (cm ³ ) - 1 : 10 for 4 hours and a low-concentrated effluent from the production of ε-caprolactam containing ε-caprolactam up to 0.5 g / dm ³ and ammonium sulfate up to 0.2 g / dm ³ at the ratio of the mass of coal (g) to the volume of wastewater (cm ³ ) -1: 100 for 24 hours, as well as heating at a temperature of 200 ° C for 1 hour in air. The extraction of dimethylamine by the obtained sorbents increases by 65.3%.

Claims (1)

A method for producing modified activated carbon, including washing industrial activated carbon (AC) with distilled water, treatment with a low-concentrated effluent from ε-caprolactam production, containing ε-caprolactam up to 0.5 g / dm ³ and ammonium sulfate up to 0.2 g / dm ³ at a ratio the mass of coal (g) to the volume of wastewater (cm ³ ) - 1: 100 for 24 hours, and further heating at a temperature of 200 ° C for 1 hour in air, characterized in that the AC is treated with a solution of potassium permanganate with a mass fraction of dissolved substances of 10% with the ratio of the mass of coal (g) to the volume of potassium permanganate solution (cm ³ ) - 1:10 for 4 hours.