RU2804782C1 - Method for producing modified activated carbon - Google Patents

Abstract

FIELD: water treatment.

SUBSTANCE: invention can be used in the production of modified active carbons used for water treatment of process effluents from chemical and pharmaceutical industries. The method for producing modified active carbon includes washing industrial active carbon (AC) with distilled water. Then AC is treated with a 1% solution of L-lysine for 24 h and heated at a temperature of 200°C in an air atmosphere for 1 hour.

EFFECT: increased sorption capacity of activated carbon with respect to dimethylamine, reduced consumption of reagents, and elimination of explosive reagents.

1 cl, 3 tbl, 3 ex

Description

The invention relates to the field of adsorption technology and can be used to produce modified active carbons (MACs) used for water treatment of process wastewater from chemical and pharmaceutical industries.

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

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

The closest is the method for producing MAU, which includes treatment with a low-concentrated wastewater 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 ) - 1:10 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 dissolved substance 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 toxicity of the reagents and the explosive properties of hydrogen peroxide.

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

The goal is achieved by washing industrial active carbon (AC) with distilled water, further processing with a 1% solution of L-lysine at a ratio of coal mass (g) to solution volume (cm ³ ) -1:100 for 24 hours, and then further heating at a temperature of 200°C in an air atmosphere for 1 hour. As a comparison, industrial activated carbon of the SKD-515 brand was used.

Example 1.

The carbon was washed with distilled water and treated with a 1% solution of L-lysine at a ratio of coal weight (g) to solution volume ( ^cm3 ) of 1:100 for 24 hours, and then heated for 30 minutes, 1, 2, 3 , 6 hours at a temperature of 200°C in an air atmosphere.

Next, adsorption was carried out on the modified samples under static conditions from aqueous solutions of dimethylamine with a concentration of 1 mol/dm ³ . The obtained data are presented in Table 1.

Example 2.

AC was washed with distilled water and treated with a 1% solution of L-lysine at a ratio of coal mass (g) to solution volume (cm ³ ) -1:100 for 24 hours, and then heated in the temperature range: 50, 100, 200 , 300, 500°C in air atmosphere for 1 hour.

Next, adsorption was carried out on the modified samples under static conditions from aqueous solutions of dimethylamine with a concentration of 1 mol/dm ³ . The obtained data are presented in Table 2.

The influence of temperature during the modification of AC on the adsorption of dimethylamine from an aqueous solution.

Example 3.

AC was washed with distilled water and treated with 0 - blank experiment, 1, 2, 5, 10% solution of L-lysine at a ratio of coal mass (g) to solution volume (cm ³ ) - 1:100 for 24 hours, and then heated at a temperature of 200°C in an air atmosphere for 1 hour.

Next, adsorption was carried out on the modified samples under static conditions from aqueous solutions of dimethylamine with a concentration of 1 mol/dm ³ . The obtained data are presented in Table 3.

The influence of L-lysine concentration during the modification process on the adsorption of dimethylamine from an aqueous solution.

As a result of the research, the following modification conditions were selected, including washing industrial activated carbon (AC) with distilled water, treatment with a 1% solution of L-lysine at a ratio of coal mass (g) to solution volume (cm ³ ) - 1:100 for 24 hours, and then further heating at a temperature of 200°C in an air atmosphere for 1 hour.

The extraction of dimethylamine by the resulting sorbents increases by 42.2%. The resulting modified active carbon can be used to purify process wastewater from chemical and pharmaceutical industries from dimethylamine.

Claims (1)

A method for producing modified active carbon, including washing industrial activated carbon (AC) with distilled water, characterized in that AC is treated with a 1% solution of L-lysine for 24 hours and heated at a temperature of 200°C in an air atmosphere for 1 hour.