SU1133832A1 - Method of sorbent activation - Google Patents

Abstract

1. METHOD FOR ACTIVATING SORBENT based on styrene and divinylbenzene for wastewater treatment and technological solutions, including processing it before use with an organic solvent and water, characterized in that, in order to increase the sorption capacity, the sorbent is sequentially treated with organic solvents with increasing dielectric permeability -. saturated hydrocarbon, carbonic ester. acids, ketone and low molecular weight alcohol. 2. Method POP.1, characterized in that hexane, heptane or octane are used as the limiting hydrocarbon, ethyl acetate or amyl acetate as the carboxylic ester, acetone or methyl ethyl ketone as the ketone, methanol or ethanol as the ketone as the low molecular weight alcohol.

Description

one

The invention relates to a method of activating sorbents used to clean process solutions and wastewater from dissolved organic compounds, for example extractants, phenols, synthetic surfactants, dyes.

A known method of cleaning salt solutions and wastewater from organic compounds by sorption on macroporous copolymer of styrene and divinylbenzene (MPS), followed by regeneration of the alcohol-Bbw sorbent with an alkali solution f. When carrying out the process of sorbing at pH 1-8, purification of dissolved extractants, for example, neutral and acidic esters of phosphoric acid, amines, chelating agents and carboxylic acids, as well as solvents of aliphatic and aromatic hydrocarbons, higher alcohols, etc., is carried out.

The disadvantage of this method is low sorption capacity, and therefore, the effectiveness of the cleaning process due to the use of macroporous copolymers as adsorbents without prior preparation.

The closest in technical essence and the achieved result is a method for activating macroporithogenic sorbent based on styrene and divinnbenzene for purifying wastewater and process solutions, in which, to increase the sorption capacity of the sorbent, it is pre-treated with organic solvent methanol and then water 2J,

The disadvantages of this method are relatively low adsorption capacity of the sorbent, as well as the use of a toxic solvent. The aim of the invention is to increase the sorption capacity of the sorbent. I

The goal is achieved by the fact that in a known method, which includes processing the op1 with an aqueous solvent and water, the sorbent is sequentially treated with organic solvents with increasing dielectric constant limit hydrocarbon acid, carboxylic acid ester, keto and low molecular weight alcohol, as well as

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by using hexane, heptane or octane as the limiting hydrocarbon, ethyl acetate or 5 amyl acetate as the carboxylic ester, acetone or methyl ethyl ketone as the ketone ester, and methanol or ethanol as the low molecular weight alcohol.

The activation method is carried out as follows. The sorbent macroporous copolymer of styrene and divinylbenzene (MPS) is placed in a glass column, and treated in the proposed sequence with each

5 with a solvent at a rate of 3 volumes per hour, and then with water. Treatment with solvents in the reverse order is less effective by 40–60% compared to processing in an increasing sequence of dielectric constant of solvents. Available, non-toxic and inexpensive solvents can be used as solvents. The efficiency of sorbent activation (MPS) by the example of extracting the dissolved extractant — tri-n-alkylamine (TAA, 126 mg / l) from sulfuric acid solutions (pH 1) at a ratio of 1: 500 volumes of sorbent to solution is given in Table 1. . I.

Not only octane, ethyl acetate, acetone and ethanol can be used as solvents, as follows from Table 1, but also hexane, amyl acetate, methyl ethyl ketone, methanol. At the same time, there is also a significant increase in the sorption capacity of the extracted organic impurities as compared with the treatment of the copolymer with methanol alone, as by a known method ..

Example 1. A copolymer is placed in a glass column and processed successively with hexane (E 1.8), amilatetate (B 4.8, methylene ethyl ketone (19), methanol (32.6) at a rate of 3 volumes per 1 volume of copolymer for 1 hour ,

0 then washed with water. When an activated sorbent is used in this way to extract TAA from a solution containing 100 mg / l TAA, 50 g / l, 50 g / l Hj, S04, npH ratio of the volumes of sorbent and 1: 500 solution and contact time 5 h, the resulting copolymer capacity TAA is 7.1 mg / g.

Example 2. The copolymer is treated successively with hexane (1.8), amylacetate (f 4.8), acetone (21) and ethanol (27.8) under the conditions of Example 1. The resulting sorbent capacity is 70.8 mg / g.

The effect of the volumetric rate of processing the copolymer with organic solvents on its sorption characteristics is given in Table 2.

As follows from the above data, the optimum is the consumption of 3 volumes of each solvent per 1 volume of sorbent per 1 hour. A further increase in the amount of solvents consumed over 1 hour to prepare the sorbent does not lead to a significant increase in its capacity.

Comparative data on the sorption capacity of industrial samples of copolymers with different specific surface, activated by the proposed method and known and used for adsorption of dissolved TAA, are given in table 3.

From the obtained results it follows that the processing of samples with an adsorbent according to this method increases the TAA capacity by 66.1, 73.4 and 71.2%, respectively. The regeneration of the adsorbents with ethanol is 100%.

Activated sorbents can be used to remove virtually all classes of water-soluble organic compounds, such as extractants, diluents, dyes, pesticides, surfactants.

Example 3. To a solution containing 2 g of an aniline acid black dye is added a sample of a copolymer activated by the proposed method. When the ratio of the volume of the adsorbent and plant

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Thief 1: 500 components are mixed for 5 hours; the dye capacity of the adsorbent is 1990 mg / g. The capacity of the same sample of the copolymer. Without processing by the proposed method is 25 mg / g. The regenerator 1 dye with an alcoholic alkali solution is 100%.

Example 4. To 1l of sulfate solution containing 64 mg

10 dissolved tetrachlorethylene diluent and 50 g of Na SO, 2 ml of activated copolymer are added. After contact for 0.5 h

15 under static conditions, the capacity of the adsorbent is 37 mg / g. The capacity of a sample of a copolymer prepared by a known method under comparative conditions is 16.2 mg / g.

20

The proposed treatment is an integral part of the method of sewage treatment and technological solutions and should be repeated after a certain number of sorption-desorption cycles when the GC capacity decreases by 20-30%. In the tested solutions, such treatment must be repeated in 7-10 cycles. The frequency of processing the IPU depends on

30 of the composition of the solutions, the type of sorbed substances and the method of regeneration of the MPS.

The technical and economic advantage of the proposed sorbent activation method is to increase the efficiency of purification of process solutions and wastewater from dissolved organic components by increasing the sorbent capacity and purification rate, reducing energy consumption associated with sorbent regeneration. In addition, the method allows disposing of the organic substances dissolved in solutions by desorption followed by

5 Ignition and return to process.

Table 1

GC without preparation (industrial sample), MPS, treated with Sosklet’s apparatus with methanol MPS, treated with ethanol, in a column at a speed of 3V per 1 V sorbent for 1 h

18.7 25.8

28.2

MPS treated with acetone in a column with a speed of 3 V per 1 V sorbent for 1 hour

MPS treated with octane, ethyl acetate, acetone, ethanol, 3 V per 1 V sorbent for 1 h

MPS, treated in columns with ethanol, acetone, ethyl acetate, 3 V per sorbent for 1 h. Note, 1. 2.

Continuation of table 1

70.4

32.5

Table 2 Sorbtsi TAA was carried out in static conditions. The ratio is 1: 500, the contact time is 5 hours. TWO is divinylbenzene.

Adsorbent,

Specific over% stitching,

% pore formation

10% DVB

100% sintin

10% DVB

100% synth a.

10% DVB

100% alkyl benzine

Table 3

TAA capacity, mg / g

I

proposed method

22.60

15.2

44.8

67.91

18.7

70.4

93.24

19.6

78.0

Claims (2)

1. METHOD FOR ACTIVATING A SORBENT based on styrene and divinylbenzene for wastewater and technological solutions treatment, including treating it before using an organic solvent and water, characterized in that, in order to increase the sorption capacity, the sorbent is sequentially treated with organic solvents with increasing dielectric constant saturated hydrocarbon, carboxylic ester, acid, ketone and low molecular weight alcohol. ' 2. The method of pop. 1, characterized in that hexane, heptane or octane is used as a saturated hydrocarbon, ethyl acetate or amyl acetate is used as a carboxylic acid ester, acetone or methyl ethyl ketone is used as a ketone, and methanol or ethanol is used as a low molecular weight alcohol. 00 oe N0> 1 1133832