SU1600842A1 - Method of flotation of coal - Google Patents

Abstract

This invention relates to the enrichment of minerals by flotation in coal preparation plants. The goal is to increase the extraction of combustible mass in the concentrate while reducing the consumption of reagents. The source coal is pulped, conditioned with a complex reagent-collector-blowing agent, and flotation is carried out. Tetrasilyl ether (TEP) of pentaerythritol (tetra (trimethylsiloxymethylene) methane) is introduced into the process as a complex reagent. The latter is obtained by reacting trimethylchlorosilane with pentaerythritol in an inert solvent in the presence of an amine to bind the hydrogen chloride formed by the reaction. In the case of adsorption on the coal surface, TEC will simultaneously exhibit both specific and universal intermolecular forces of interaction with the positive and apolar regions of the coal surface. This determines their high value and adsorption energy on the coal surface. This determines their high value and adsorption energy on the coal surface. The organosilicon compounds are very good water-repellent mineral surface adsorption, which has a positive effect on their flotation activity.

Description

The invention relates to the field of mineral processing by flotation and can be used in coal preparation plants.

The purpose of the invention is to increase the recovery of the combustible mass into the concentrate while reducing the consumption of reagents.

The flotation method is carried out as follows.

The original coal is pulped, conditioned with a complex reagent by a blowing agent collector, followed by coal flotation. Pentaerythritol tetrasilyl ether is introduced into the process as a complex reagent.

tetra (trimethylsiloxymethylene) methane of the general formula (I)

X)

four;;

about

CHj-Si-OCH

v

CHz CHj

CH -Sr-OCH

CHjO-Si-CH c.

CH O- Si-CH CH3 CH3

Pentaerythritol tetrasnyl ester (.1) is obtained by reacting triethylchlorosilane with pentaerythritol in an inert solvent (hexane, heptane) in the presence of a tertiary amine to bind the hydrogen chloride formed by the reaction.

Physical and chemical characteristics:

ten

, 253 ° С (757 mm Hg), h 1, А180, 8765.

Example. To carry out the process, we take a portion of coal, for example, 100 g, mixing} with water in a laboratory machine of the Mechanobr t5 type with a chamber volume of 0.75 liters for 120 seconds, then a portion of the complex reagent, tetrasilyl ether of pentaerythritol, is fed and contacted with coal pulp in te- 20. value 60 s. After 60 seconds of contacting the reagents with the pulp in the flotation machine, the submerged air is removed from the air, and then the flotation concentrate is removed for 60 seconds.

The air supply to the slurry is stopped and the next portion of the complex reagent is supplied, followed by their contacting with coal 3 for

60 s.

After contact of the coal sample with reagents, air is again fed to the pulp and the second concentrate is removed, the total consumption of reagents and the amount of dosing into the pulp are determined by their flotation activity.

The use of pentaerythritol tetrasilyl ether as a complex reagent instead of tractor kerosene with bottom residues of butyl alcohols makes it possible to increase the extraction of the combustible mass in the concentrate from 78.5-92.7 to 92, A-93.3% while reducing the consumption of reagents that from 0.565-0.900 kg / t to 0.410-0.550 kg / t. The use of pentaerythritol tetrasilyl ether as a complex reagent compared to tractor kerosene leads to an increase in the extraction of the combustible mass in the concentrate from 78.5 to 93.3% with an equal reagent consumption of 0.550 kg / ton.

The improvement in coal flotation using pentaerythritol tetrasilyl ether is explained by the elemental composition and structure of its molecule.

 .

In the molecule of tetrasyl ester j of pentaerythritol, the electron density is localized on oxygen atoms; as a result, the reagent can specifically interact with sorption-active centers of the coal surface that carry a positive charge (protonized hydrogen atoms of the phenolic and carboxyl groups in the macromolecule of the organic mass of coal) pattern

,

l

 Sl-CH3) / t

sn

.

five

In the molecule of pentaerythritol tetrasilyl ether, there are hydrocarbon radicals that can interact with apolar centers of the coal surface due to intermolecular Wander-Waals forces: a.

Therefore, in the case of the adsorption of pentaerythritol on the carbon surface of tetrasilyl ether, both specific (H-bonds, etc.) and universal non-specific intermolecular forces of interaction with the positive and apolar portions of the coal surface appear simultaneously. This determines their high inu value and adsorption energy on the coal surface. At the same time, organosilicon compounds are very good hydrophobicizers of the mineral surface upon their adsorption, which positively affects their photoactivity. The presence of four oxygen atoms in the pentaerythritol tetrasyl ether molecule gives them a high surface activity. The high polarization of the reagent molecules, caused by the electron-acceptor properties of oxygen atoms, causes good foaming properties.

High hydrophobatic activity and good foaming properties of pentaerythritol tetrasilyl ether ensure their high flotation properties.

Consequently, the use of pentaerythritol tet-, rasilyl ether as a complex reagent during flotation allows to increase the extraction of the weight of the mass into horses, the enrate, from 7 to 92.4-93.3% with simultaneous 16008426

To reduce the consumption of the reagent-collector, the foaming agent is introduced 1, j 2.0 times. Pentaerythritol tetrasyl ether

Claims (1)

formulas Method of coal flotation, inclusive ,, Q: nruou gf c-v-u pulping, conditioning 3 .-. pulp with collector and foaming- ru, pu o ri ,, Lem and the release of combustible mass in the foam Q 3 Ny product, imitating-CH -Sl-OCHo SNPO GCH-g so that, with the aim of increasing i- / / attraction of combustible mass, as Hj СНо