RU2809093C1 - Method of preparing carbon sorption nanomaterial from biochar by electromagnetic method - Google Patents

Abstract

FIELD: sorption chemistry.

SUBSTANCE: following has been proposed: a method of preparation of carbon sorption nanomaterial from biochar in an electromagnetic way, including obtaining the original biochar from rice husk by carbonization of the original rice husk in a muffle furnace at a temperature of 600°C for 30 minutes with pre-washing, processing of the resulting initial biochar from rice husk in a process activation apparatus for processing materials, according to which a sample of the resulting initial biochar from rice husk was mixed in distilled water and exposed to a rotating electromagnetic field with ferromagnetic particles m=200 g for 30 seconds in a process activation apparatus for processing materials, after which it was dried in an oven for 4 hours at t=105°C.

EFFECT: obtaining an effective sorbent using the method preparation of carbon sorption nanomaterial from biochar by the electromagnetic method with its subsequent use for the purification of natural and wastewater at municipal and industrial facilities.

4 cl, 3 dwg, 1 tbl

Description

There is a known method for the production of biochar-based sorbent and thermal energy from sunflower husks and an installation for its implementation (RU 2 763 291, IPC: B01J 20/20, patent publication 12/28/2021), which consists of thermal processing of sunflower husks, and thermal processing of the husks sunflower is carried out by vortex oxidative pyrolysis, while drying of sunflower husks begins before entering the reactor, in a mixer; sunflower husks from the receiving hopper through an axleless screw conveyor enter the feed hopper, then through a screw feeder into the mixer, where hot steam-gas pyrolysis products taken from an air-cooled cyclone are simultaneously supplied, then the mixture of sunflower husks and steam-gas pyrolysis products passes through a recirculation fan and is fed through a direct-flow a burner with a divider into a vortex cyclone reactor, in which oxidative pyrolysis begins at temperatures of 300-400°C; simultaneously with the introduction of sunflower husks into the same zone of the vortex cyclone reactor, hot secondary blast air, heated in the cooling casing of the air-cooled cyclone, is tangentially supplied, and oxidative pyrolysis ends in the air-cooled cyclone at temperatures of 330-420 ° C, while simultaneous separation from the steam-gas pyrolysis products of solid particles, which fall into a heat-insulated collection hopper and represent a biochar-based sorbent, and vapor-gas products of oxidative pyrolysis exit the air-cooled cyclone and leave the installation.

The disadvantage of this known method is the limited temperature range, which does not allow choosing a heat treatment mode at a higher temperature.

There is also a known method of counter-vortex processing of raw materials and a counter-vortex layer apparatus for processing raw materials (patent of the Russian Federation No. 2771497, publ. 05/05/2022), which uses the energy of a rotating constant magnetic field to process various types of raw materials, acting on ferromagnetic elements that directly interact with the processed raw materials. A counter-vortex layer apparatus for processing raw materials, containing a removable working chamber with ferromagnetic elements docked to the lower part of the apparatus body, a rotating magnetic head located in the upper part of the working chamber, inlet and outlet pipes, while an additional counter-vortex layer is located in the upper part of the working chamber. a rotating magnetic head installed offset in a horizontal plane relative to the first magnetic head, an output chamber is installed under the working chamber, separated from the working chamber by a screening unit for ferromagnetic elements, while a plug with a magnet is installed at the bottom of the output chamber, the inlet pipe is located in the upper part of the working chamber opposite the magnetic heads, and the outlet pipe is located in the outlet chamber.

The disadvantage of this known method is the installation of rotating magnetic heads, which complicate the technological process of processing the material.

The closest to the claimed is a method for producing activated carbon powder (RU 2 769 520, IPC: C01B 32/312, patent publication 04/01/2022), by exposure to ferromagnetic elements in the rotating electromagnetic field of a vortex electromagnetic apparatus, including loading, grinding, activation with water vapor at high temperature and unloading. Water is supplied directly to the active zone of the apparatus, where grinding and activation occurs upon collision of ferromagnetic activating elements with coal raw materials - anthracite chips and water vapor at a temperature of more than 250 ° C, formed due to the conversion of the kinetic energy of moving elements into thermal energy, and the unloading of the finished product is carried out by a controlled air flow, removing fractions of the required granulometric composition from the active zone.

The disadvantage of this known method is the need to supply compressed air, which requires the installation of additional equipment, which in turn complicates the technological scheme for obtaining the powder, which generally increases the cost of sorbent production. In addition, the fractional composition of coal after processing on a vortex layer apparatus in this case was 0.07-0.10 microns, which exceeds the size of the sorbent obtained by the claimed method.

The purpose of the present invention is to obtain an effective sorbent by preparing carbon sorption nanomaterial from biochar using the electromagnetic method for the purpose of its subsequent use for the purification of natural and wastewater at municipal and industrial facilities.

This goal is achieved by the fact that in the proposed method of preparing carbon sorption nanomaterial from biochar, the material being processed is crushed by electromagnetic method, structured, and its chemical composition is also optimized.

Raw rice husk (straw) biochar is produced by carbonizing raw rice husk (straw) in a muffle furnace at 600°C for 30 minutes with pre-washing. Rice husk (straw) biochar was further processed in a process activation apparatus for materials processing (RU 2170707, IPC: C02F 1/48, patent publication 07/20/2001). A sample of rice husk (straw) biochar was mixed in distilled water, placed in a non-magnetic cylinder with ferromagnetic particles m = 200 g, then exposed to a rotating electromagnetic field for 30 seconds in a process activation apparatus for processing materials, and then dried in a drying oven for 4 hours at t=105°C. Ferromagnetic particles rotating in an electromagnetic field cause a magnetostriction effect, leading to the reduction of oxides on the surface of particles of the processed material. The method makes it possible to increase the carbon content in the sorbent from 43.3 to 78.5% compared to the original biochar (Fig. 1, Table 1), reduce the content of impurities in the sorbent, and also grind the sorbent to nanosizes of 1-50 nm with the formation of pores with a diameter of up to 1 nm (Fig. 2,3), thereby increasing the homogeneity of the composition. 5 This method made it possible to prepare a carbon sorbent, which has confirmed its effectiveness in treating wastewater in laboratory conditions.

Brief description of drawings

Fig. 1 Chemical composition of rice husk biochar treated by electromagnetic method.

Fig. 2 Micrograph of the surface of a rice husk biochar particle treated by electromagnetic method, M 1:2 nm.

Fig. 3 Micrograph of the surface of a rice husk biochar particle treated by electromagnetic method, M 1:10 nm.

Composition of feedstock. The quality indicators of the original rice husk (straw) biochar and rice husk (straw) biochar with electromagnetic treatment are shown in Table 1.

Table 1 – Chemical composition of the obtained rice husk biochar samples with and without electromagnetic treatment

Sorbent type WITH, % O, % Si, % K, % Ca, % Mg,% Na, % Cl, % Fe,% Al,% 1 2 3 4 5 6 7 8 9 10 eleven Rice Husk Biochar with Electromagnetic Treatment 78.5 18.5 2.1 0.5 0.1 0.1 0.1 - 0.1 - Rice Husk Biochar 43.3 42.5 8.2 1.0 1.1 0.9 0.4 0.1 - 2.7

Claims (4)

1. A method for preparing carbon sorption nanomaterial from biochar by the electromagnetic method, including obtaining initial biochar from rice husk by carbonizing the original rice husk in a muffle furnace at a temperature of 600°C for 30 minutes with preliminary washing, processing the resulting initial biochar from rice husk in an activation apparatus processes for processing materials, according to which a sample of the resulting initial biochar from rice husk was mixed in distilled water and exposed to a rotating electromagnetic field with ferromagnetic particles m = 200 g for 30 seconds in a process activation apparatus for processing materials, after which it was dried in a drying oven for 4 hours at t=105°C. 2. The method according to claim 1, characterized in that the method of preparing carbon sorption nanomaterial from biochar by the electromagnetic method makes it possible to increase the carbon content in the sorbent from 43.3 to 78.5% compared to the original biochar, and to reduce the content of impurities in the sorbent. 3. The method according to claim 1, characterized in that the method of preparing carbon sorption nanomaterial from biochar by the electromagnetic method ensures that the resulting material reaches nanosizes. 4. The method according to claim 1, characterized in that the method of preparing carbon sorption nanomaterial from biochar by the electromagnetic method makes it possible to obtain porosity in nanoparticles up to 1 nm in size.