SU1028683A1 - Process for preparing water-soluble polyelectrolyte - Google Patents

Abstract

1. A method for producing a water-soluble polyelectrolyte by copolymerization of (meth) acrylic acid, an almonic acrylate and a nitrogen-containing monomer in the presence of a peroxide initiator at 50-70 ° C, characterized in that, in order to increase the flocculation capacity of polyextrolite, as a means of the flow, also, in a case, you also have a means of the product, which is also in a case of . 2. The method according to claim 1, wherein the copolymerization is carried out at a molar ratio of (meth) acrylic acid, ammonium acrylate and ammonium maleic acid, pciBHOM 1-2: 0.25-1: 0.5-1 respectively.

Description

This invention relates to a process for the preparation of water-soluble polyelectrolytes (PE) based on unsaturated carboxylic acids, their derivatives, and maleic anhydride (acid) derivatives. PE can be used as flocculants in wastewater treatment of electroplating plants.

Known methods for producing water-soluble PE by copolymerization of meth (acrylic) acid and ammonium carbon - PAH mass at 75-80 ° C in one stage for 20 minutes. in the presence of hydrogen peroxide, as well as copolymerization of acrylic acid, ammonium acrylate and sodium silicate - PAA5 under similar conditions fl J.

The closest to the proposed technical essence and the achieved effect is the method of obtaining water-soluble PE by copolymerization of acrylic acid, ammonium acrylate and sulfamic acid - CAAS in the presence of hydrogen peroxide as an initiator at 50-60 ° C for 10-20 minutes, CAAC has anidic, carboxyl, carboxylate and sulfo groups. It has flocculating properties, is highly soluble in water, forms persistent viscous solutions 21.

However, known PEs are not characterized by a high flocculating ability.

The purpose of the invention is to increase the flocculating ability of PE.

This goal is achieved by the fact that according to the method of obtaining water-soluble. PE by copolymerising (meth) acrylic acid, ammonium acrylate and a nitrogen-containing monomer in the presence of a peroxide initiator in SO-TO C, ammonium maleic acid is used as the nitrogen-containing monomer.

The copolymerization is carried out at a molar ratio of (meth) acrylic acid, ammonium acrylate and ammonium maleic acid, equal to 1-2: 0.25-i 0, 5-l, respectively.

The PEs obtained by the proposed method have in their composition carboxyl, carboxylate, amide functional groups, which together give them amphoteric properties and effectiveness in disperse-systems,

The method is as follows.

The calculated amounts of acrylic (methacrylic) acid, acrylate (methacrylate) ammonium and maleic acid abd U1 are shifted. To the resulting mass, 30% hydrogen peroxide is added in an amount of 0.11, 0% by weight of acrylic (methacrylic) acid and acrylate (methacrylate a) ammonium, mix thoroughly and heat in a water bath

10 to 50-70 s. The copolymerization start-up reaction at this temperature takes 4-10 minutes, and is accompanied by the release of heat and water vapor. As a result,

5, the temperature of the reaction mass in the process of copolymerization to 120-150 ° C occurs the process of amidation. carboxylate ammonium groups with the release of water. As a result, a porous mass is obtained, which, after solidification at room temperature, can easily be crushed to a powdery state. The PE obtained by this method is good.

The r are dissolved in water and form viscous stable solutions.

The composition and structure of polyelectro. SMAU litas are determined by IR spectroscopy, elemental analysis, and potentiometric titration of their aqueous solutions and model systems.

Example. 144 g (2 mol) 5 acrylic (174 g (2 mol methacrylic acid) acid, 89 g (1 mol) acrylate (103 g (1 mol) methacrylate); 1 MMy and 70 g (0 , 5 mop maleic acid ammonium mixture carefully

0 mix, add 0.1-1.0% (to the amount of acrylates) hydrogen peroxide, mix and leave to stand in a water bath, stirring occasionally. When the reaction mass reaches 50-70 s, the copolymerization reaction starts, the temperature of the reaction mass spontaneously rises to 120-150 ° C, water vapors are released and

Q is a porous product that solidifies and easily crushes i.p. powder upon cooling. Output 92-96% of theoretical. To obtain pure PE for Exact Chemical

It is dissolved in water in analysis.

set in acetone and dried at.

Example 2. Conducted after. All these actions are valid. 0 Observe the reaction conditions as in Example 1 / but with different ratios of acrylic (methacrylic) acid, achrylate (methacrylate) ammonium and maleic acid ammonium, respectively 2: 0.25: 1.

The proposed polyelectrolytes are tested as flocculants during purification of wastewater from electroplating plants with the following parameters: pH 9.18, suspended substances .193 mg / l / metal ion content, mg / l: Cu, 16,, 5, Zn 5.08 ; C g 2.74.

In tab. Table 1 shows the data on the effect of the type and dose of polyelectrolytes on the deposition of metal ions from the wastewater of electroplating industries, which grew by 10 minutes.

Take optimal doses of effective flocculation. In purified water using the proposed SMAU polyelectrolyte, there are fewer metal ions compared to analogs and controls. In addition to the high efficiency offered compared to analogues of the base and control MPCs (molten metals discharged in water) in purified water using the proposed polyelectrolyte fully meets the requirements MPC and better than it, which allows to get water not only for dl. recycling water supply, but also, its release in open water reservoirs and waste disposal.

In tab. 2 shows the data to determine the effectiveness of the compared polyelectrolytes during deposition; suspended substances in the same wastewater.

A comparison of the sedimentation rate of suspended solids shows a high efficiency of SMAU in comparison with analogues and controls, as well as with polyacrylamide.

The effectiveness of the proposed, analogs, PAL and control

0 on another real wastewater of the electroplating plant with the following parameters: pH 9.02; the content of cobalt ions, mg / l: Fe - 100; 18; Zn 21; Cr 9, Mi 1.9. After 5 .min upholding

5, the content of metal ions in wastewater with the introduction of polyelectrolytes decreased as follows. Here, it can be seen that the proposed PE also has a different effect on other wastewater.

0 veins compared with analogues and controls. The effectiveness of SMAU on this waste water is 2 or more times more efficient than its analogues.

five

The use of the proposed PE: as a flocculant in wastewater treatment, can have an effective effect on the solution of the issue of protection and rational use,.

0 no water resources. ;

 - Table

T a b L and c. a 2

Table 3

Claims (2)

1. METHOD FOR PRODUCING A WATER-SOLUBLE POLYELECTROLYTE by copolymerizing (meth) acrylic acid, ammonium acrylate and a nitrogen-containing monomer in the presence of a peroxide initiator at 50-70 ° C, which involves increasing the flocculating ability of the polyelectrolyte as nitrogen monomers use ammonium maleic acid. 2. The method of pop. ^ characterized in that the copolymerization is carried out at a molar ratio of (meth) acrylic acid, ammonium acrylate and ammonium maleate, equal to 1-2: 0.25-1: 0.5-1, respectively.