SU715467A1 - Method of fluorine extraction from solutions - Google Patents

Description

(54) METHOD OF EXTRACT. FLUOR FROM SOLUTIONS

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The invention relates to the field of fluorine extraction from aqueous solutions of 5 fluorine-containing liquid waste, waste water

There is a known method of extracting fluorine from solutions by sorption with a haze: inorganic sorbents. As sorbents, activated aluletne oxide is used, hydroxylapatite is a disadvantage of the method - low degree of recovery, as well as rapid destruction of sorbents 1.

A known method of extracting fluorine from solutions by sorption on anion exchange resin. type AV-16G or EDE-UP.

The capacitance of the AB-16G anion exchanger with respect to fluorine is 1.06 g / l, the capacity of EDE-Yu is less than 1.06 g / l. Fluorine desorption is carried out with 3-5% solution of sodium or ammonium alkali 2.

The disadvantage of this method is the low degree of extraction of fluorine due to the low capacity of the anion exchange resin.

The purpose of the invention is to increase the degree of fluorine recovery by increasing the capacity of the anion exchanger.

The goal is achieved by the fact that fluorine is extracted from solutions by sorption on anion exchange resin, followed by desorption with ammonia solution, and before sorption

the solution processes with formalin in the amount of 2.5-40 g per 1 g of fluorine.

Sorption of fluorine from a formalin-treated solution is carried out on an EDE-UP organic anion exchanger, which is a product of polyamine polycondensations with epichlorohydrin.

The addition of formalin in the amount of less than 2.5 g per 1 g leads to a decrease in the capacity of anion exchange resin and a decrease in the degree of extraction.

The introduction of formalin in the amount of 40 g per 1 g of fluorine is necessary to compensate for the decomposition of formalin by foreign substances present in the production solutions.

the addition of formalin more than 40 g per 1 g of fluorine is undesirable, an excess of formalin entails contamination of the fluorine-purified solution.

Formalin during the processing of the solution decomposes. Further, the solution does not cause any harm to the environment. Desorption of fluorine from the anion exchanger causes 3–10% padTBopoM of ammonia to settle.

PRI me R. Into the reactor pour 2 l of liquid waste with a pH of 6-8, containing 0.25 g / l of fluorine, a certain amount of 37% formalin solution.

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SucceedsMy vdverzhivayut over 1 h at kmnyyy temperature, and then passed through a column in which. load 5.0; .ml orgamychёbkub anion exchanger EDE-10P in OH-form, with a speed of I 5O MD / h. At the exit of the column, I get a water-tail-raising rass.tvor, cleared: from. Fluoride Sanitary Standards, Results. fluorine sorption, depending on the amount of added (formalin is present in the table .. -. - Fluorine desorption. is carried out .5.% - Scientific research institute / ammonia solution. A commercial fraction of desorbate containing 8 g / l of ammonium fluoride is obtained, which Can be used in a company / techory: business operations.

Proposed. The method allows comparing with the prototype to increase the degree of fluorine extraction by 2 times. increase the volume of the purified solution in one cycle of sorption by 4 times; reduce the frequency of regenerations and the volume of regenerating solutions by 4 times.

Claims (2)

. . Invention Formula . In order to extract fluorine from solutions, including sorption on anion-exchange and desorption, we dissolve ammonia, oTJi.H .4 a.yu and i. With the fact that, in order to increase the degree of extraction before sorption, the solution is treated with formalin in an amount of 2.5 -40 g per 1 g of fluorine. . :. . Sources of information taken into account in the examination 1, Klchko V.A. Apeltsin I.E. Purification of natural waters. M., stroiizdat, 1976, p. 436. -. ;. 2. Malting. V.A. Shmitd M.I. Ochistka wastewater in the chemical industry, Chemistry, 1977, p. 329 (prototype).