CS274340B1 - Method of surface-active substances removal from aqueous solutions - Google Patents

Abstract

The solution concerns a method of removing superficially active substances from water solutions using sorbent and its simultaneous regenerations. The principle of the solution according the invention consists in the fact that the water solution of superficially active substances is introduced into contact with polymeric sorbent based on copolymers of 2,3-oxypropylmethacrylate, 2-hydroxyethylmethacrylate, 2,3-dihydropropylmethacrylate, methylmethacrylate and acrylate with 20 to 95 percent by weight of ethylenedimethacrylate with sorptive capacity up to 0.38 mmoles/g and the retained superficially active substances are isolated from the sorbent. This method of usage of the above mentioned sorbents can be performed in simple continuous units directly in the technological process enabling waste-less technology.

Description

The present invention relates to a process for removing surfactants from aqueous solutions using a sorbent and regenerating it simultaneously.

In a number of industries, waste water is produced, which is contaminated with surfactants. These include water scrubbers in the photographic industry, electronics industry and elsewhere.

According to the present state these substances are captured, but incompletely during biological treatment. Oak has emerged from a literature review of these substances are also captured by macroporous sorbents based on styrene-divinylbenzene copolymers. (T. Saito, K.Higashi, G.Nuzakani, K.Nagiwara, Adsorption of Synthetic Organic Substances Using Polymeric Adsorbent, Water Purif. And Liuuid Wastes Treat., 1978, 19 (No 9), 825-832; ESSvarcman, VVPodlesnjuk, TMLevchenko, NAKlimenko, Adsorption of surfactants from solutions by various polymeric sorbents and activated carbon (Russian), Water Chemistry and Technology 1987, 9 (No 1), 26-27).

It has now been found that a higher effect can be obtained by the method of removing surfactants from the aqueous solutions of the present invention, which comprises contacting the aqueous surfactant solution with a polymeric sorbent based on 2,3-oxipropylmethacrylate copolymers. % hydroxyethyl methacrylate, 2,3-dihydropropyl methacrylate, methyl methacrylate and acrylate with 20 to 95 wt. ethylenedimethacrylate having a sorption capacity of up to 0.38 mmol / g and the entrapped surfactants are isolated from the sorbent.

A further feature of the process according to the invention is that by increasing the free energy of the surfactant mycel formation above the free adsorption energy by 10 kO / mol, the isolation of the surfactants from the sorbent is effected with the same surfactant solution with a concentration higher than the critical concentration. mycel formation.

The isolation of the surfactant while regenerating the sorbent can be carried out by the process of the invention such that the surfactant is isolated from the sorbent by elution with an organic solvent of the group consisting of: from methanol, ethanol, isopropanol and acetone.

The removal of surfactants from aqueous solutions by the process of the invention is a simple and efficient process for obtaining surfactants which can be returned to the process while the sorbent is regenerated.

Using such sorbents, this process can be carried out in simple continuous units directly in a process enabling waste-free technology.

CS 273 340 Bl

The invention is illustrated by the following non-limiting examples.

Example 1

0.17 parts of a polymeric sorbent based on macroporous copolymers of glycidyl methacrylate with tyhlendimetha2 crystal (95% by weight) having a specific surface area of 367 was introduced into a solution of surfactant, oxiethylated isooctylphenol having an oxiethylene unit number of 10 (50 parts) at a concentration of 337 mg / l. m / g, sorbed with stirring to equilibrium. After filtering out the solution, the aqueous phase contained 0.1 mmol / l surfactant. The sorbent absorbed 0.22 mmol of surfactant per g of dry sorbent, representing 12 wt.

Example 2

0.1 g of a polymeric sorbent containing 60 wt. % oxipropyl methacrylate with 40 wt. ethylene dimethacrylate having a specific surface area of 66 m / g. Upon reaching the sorption equilibrium, the equilibrium concentration of the surfactant in the solution was 0.2 mmol / g. The capacity of this sorbent was 0.06 mmol / g.

When the initial surfactant concentration in water was increased to 0.9 mmol / l under the same conditions (25 ° C), the surfactant was completely desorbed from the sorbent.

Example 3

The sorbents of Examples 1 and 2 can be regenerated by washing with 1.5 volumes of methanol, ethanol or acetone per volume of sorbent and 1.5 volumes of water. It can then be reused for the sorption of surfactants.

Example 4

The sorption property of the sorbent as a function of the composition It is shown in Fig. 1, where the sorption isotherms, i.e. the concentration of the sorbed surfactant (mmol / g) and the surfactant concentration in the solution (mmol / 1), are shown for lower copolymers. glycidyl methacrylate.

Copolymer containing curve O = 5 wt. glycidyl methacrylate curve -} - = 40 wt.%, glycidyl methacrylate curve = 60 wt. glycidyl methacrylate curve Λ = 70% wt. glycidyl methacrylate

CS 274 340 B1 and denotes the absorbed surfactant concentration (mmol / g) c denotes the surfactant concentration in solution (mmol / g)

Claims (3)

SUBJECT OF THE INVENTION A method for removing surfactants from aqueous solutions, wherein the aqueous surfactant solution is contacted with a polymeric sorbent based on copolymers of 2,3-oxipropyl methacrylate, 2-hydroxyethyl methacrylate, 2,3-dihydroxypropyl methacrylate, methyl methacrylate and acrylate % with 20 to 95 wt. ethylenedimethacrylate with a sorption capacity of up to 0.38 mmol / g and the entrapped surfactants are isolated from the sorbent. 2. A method according to claim 1, wherein by increasing the free energy of surfactant mycel formation above the free energy by adsorption of 10 kJ / mol, the surfactant isolation from the sorbent will result in the same surfactant solution having a higher surfactant concentration. than the critical concentration of mycelial formation. 3. The process of claim 1, wherein the surfactant is isolated from the sorbent by elution with an organic solvent selected from the group consisting of methanol, ethanol, isopropanol, and acetone.