RU2408422C1 - Method of producing sorbent - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to environmental protection, namely to method of producing sorbent for reducing gas pollution of working space by organic contaminants. Montmorillonite clay with content of montmorillonite of 95% is activated in magnetic field for 30 s at magnetic induction equal to 0.011 T, and in 48 h, thermal treatment if performed at 453 K for 1 h.

EFFECT: efficiency in decontamination of industrial materials and premises.

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Description

The invention relates to the field of environmental protection, and in particular to a method for reducing the emission of highly toxic free formaldehyde monomer from an adhesive composition based on urea-formaldehyde resin. The method is applicable at enterprises using production materials containing toxic compounds and having wastes that include these compounds, including furniture enterprises.

A known method of producing a sorbent for aeration tanks of a biochemical installation, selected as a prototype, characterized in that montmorillonite clay with a content of montmorillonite of 60-70% is activated with an 80% solution of orthophosphoric acid at a temperature of 80-90 ° C for 4 hours at a weight ratio sorbent: phosphoric acid 1: 3 [Patent Ru No. 2333791 C1 B01J 20/12 (2006.01), C02F 1/28 (2006/01) [Text] / Belchinskaya LI, Kozlov K.A., Bondarenko A.V. ., Chitechan S.S .; applicant and patent holder VGLTA. - No. 2007124971/15; declared 07/02/2007; publ. 09/20/2008. Bull. No. 26]. This cleaning method is very effective in cleaning water bodies, but is not used for adsorption of toxicants from the gas phase.

The invention solves the problem of reducing gas contamination by organic pollutants in industrial premises. This is achieved by the fact that in a method for producing a sorbent comprising activating montmorillonite clay, according to the invention, clay with a content of 95% montmorillonite is activated for 30 s with a pulsed magnetic field with a magnetic induction of 0.011 T and after 48 hours it is heat treated at 453 K for 1 hour

To determine the optimal conditions for the activation of montmorillonite clay, the following studies were carried out.

Experience 1.

The adsorption-structural characteristics of activated sorbents depend on the initial mineral composition of natural clays.

It is known [Belchinskaya L.I. A complex of environmental technology solutions using varnish compositions and resins in the woodworking industry. “Diss ... doctorate.” tech. Sciences., - Voronezh, 1996. - 534 pp.], that with an increase in the content of montmorillonite, its adsorption capacity is enhanced. Therefore, a sample with a maximum content of natural montmorillonite was selected. A higher (over 95%) content of the rock-forming component in clays is not detected. Specific surface area (S), porosity (P), and monolayer capacity (a) were used as evaluation criteria.

The data are presented in table 1.

Table 1 The sorbent content,% S, m ² / g R, % a, mg / g 32 112.35 29.56 36.45 55 122.69 29.89 45.87 78 138.42 31.54 48.32 95 152.65 36.12 52.02

According to the data in Table 1, clay with a content of montmorillonite of 95% has the best indicators for all evaluation criteria.

Experience 2.

The optimal processing time in a pulsed magnetic field was determined by evaluating the adsorption properties of activated montmorillonite. The data obtained are shown in table 2.

table 2 Exposure time, s Sorption capacity, mg / g 10 twenty thirty 40 32.6 61.2 71,4 58.6

An increase in adsorption capacity was observed in the range of 10-30 s. At 40 s, the adsorption of formaldehyde by an adsorbent modified by a pulsed magnetic field decreases. Thus, a treatment time of 30 s is optimal for increasing the efficiency of the sorbent.

Experience 3.

Magnetic induction of a pulsed magnetic field (B) is the main factor in creating a new sorbent with the best adsorption. The decrease in magnetic induction contributes to a significant activation of the sorption material.

Table 3 B, T a, mg / g 0,200 12.91 0,100 55.02 0,050 60.25 0.011 71.04 0.005 64.12

Sorption capacity has maximum values at B = 0.011 T.

Experience 4.

To enhance the effect of a pulsed magnetic field, the montmorillonite sample was heat treated. The optimal heat treatment mode of the sample is established. The results are presented in table 4.

Table 4 Exposure time, h Processing temperature, K 398 433 453 473 0.5 46.2 47.6 48.0 47.5 one 48.6 50,0 52,4 50.23 2 47.3 48,2 49.1 49.0

The highest adsorption ability after thermal modification is possessed by a sample processed for an hour at 453 K.

Experience 5.

The time of maximum activation of the sample after the action of UTI with B = 0.011 T was determined. The results are presented in table 5.

Table 5 Sorption capacity, mg / g Time after exposure to a pulsed magnetic field, h 12 24 36 48 60 72 18.6 27.98 60.25 71.04 58.64 36.58

The maximum sorption ability is manifested 48 hours after exposure to a pulsed magnetic field.

Experience 6.

The desorption values of formaldehyde from a sorbent with a 95% content of montmorillonite activated for 30 s in a pulsed magnetic field with a magnetic induction of 0.011 T and after 48 h heat-treated at 453 K for 1 h are presented in Table 6.

Table 6 Desorption, mg / g Magnetic induction, T 0.2 0.1 0.05 0.011 0.005 17.4 5.56 2.64 0 2.02

The combined treatment, in a pulsed magnetic field and thermally during the maximum response to the field effect, is most effective at B = 0.011 T, since desorption processes are completely absent.

Claims (1)

A method of producing a sorbent, including activation of montmorillonite clay, characterized in that clay with a content of 95% montmorillonite is activated for 30 s with a pulsed magnetic field with a magnetic induction of 0.011 T and after 48 hours heat treatment is carried out at 453 K for 1 h.