SU1065350A1 - Method for preparing effluents phenols - Google Patents

Abstract

1. METHOD OF CLEANING WASTE WATER FROM PHENOLS, including catalytic oxidation of the latter in the presence of transition metal compounds, characterized in that, in order to simplify the cleaning process, oxidation is carried out with oxygen, and as compounds, transition metals take their complexes with polyethyleneimine. 2. The method according to claim 1, which is different. We use the complexes med11, cobalt, iron and manganese. 3. The method according to claim 1, about tl and h and y and the fact that oxidation is carried out at pH 7-10 (L with

Description

about: l

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The invention relates to methods for purifying wastewater from phenols and can be used in the purification of industrial effluents from pulp and paper and coking industries.

A known method of purification of wastewater from phenolic organic compounds, in particular quinone, by sorption it on water-insoluble polymeric mercaptans, in particular on thiopolivinylphenyl ether. The thiopolivinylphenyl ether is kept in contact with 20 ml of an aqueous solution of quinone with a concentration of 10.8. Mg / l at 20 s for one hour, periodically shaking. Then the filtrate is separated. Purification rate is 73.8% l.

The disadvantage of this method is the low degree of wastewater treatment. The closest to the proposed technical essence and the achieved result is a method of purification of wastewater from phenolic compounds by liquid phase catalytic oxidation with concentrated hydrogen peroxide at pH 4-6 in the presence of metallic iron or copper and salts of sodium, copper, nickel and manganese as catalysts. the subsequent neutralization of those that have become acidic: (pH 1.5-1.9) as a result of the reaction of the oxidation of wastewater with calcium hydroxide and the separation of sludge. The method allows to increase the degree of purification to 100% 12.

The disadvantage of this method is the high consumption of reagents, the difficulty of treating large volumes of effluent and the inevitability of secondary contamination of water with oxidation products of organic compounds, which complicates the whole process.

The aim of the invention is to simplify the process of CLEANING,

This goal is achieved by a purification method involving the catalytic oxidation of phenols in the presence of polyethylene complexes and transition metal ions with oxygen.

In this case, complexes with divalent ions of cobalt, copper, iron, and manganese are used. Oxidation is carried out at pH 7-10.

The method is carried out as follows.

To prepare the complex, an aqueous solution of the transition metal salt and dibromopane as a binder (addition of binder, metal ions, and polyethylene ilement units 20: 2: 100) are added to the 5% alcoholic solution of polyethylenimine. The reaction mixture is heated with stirring in a water bath at 60-70 ° C for 1015 hours. After the completion of the reaction, the polymer is washed with cold ethanol and dried. Waste water is poured into the resulting complex, oxygen is passed through the mixture.

The essence of the method of purification of wastewater from phenols is that catalytic oxidation of phenol with oxygen to quinone, which, unlike the original phenolic compound, chemically reacts with free amino acids, occurs at the active sites of the catalyst, which is a complex of transition metal ions with amino or imino groups of the polymer. - and the imino groups of the polymer irreversibly bind to it.

Example 1. 0.1 g of the complex Cu (| I) - polyethylenimine is placed in a flask, 15 ml of 510 m of hydroquinone are poured in a reverse buffer solution (pH 9) and oxygen is passed through the reaction mixture with stirring on a magnetic stirrer. Samples are taken at certain time intervals, the amount of hydroquinone remaining is filtered and the amount of hydroquinone remaining is determined spectrophotometrically in the range of 270-290 nm.

Determination of the polymer adsorption capacity under static conditions showed that 1, g sorbent is capable of absorbing 0.366 g of quinone.

The implementation of the method where either 1,4-diphenol and pyrocatechin is taken as phenolic compounds is carried out in the same manner. At certain time intervals, samples are taken and the degree of purification is determined. The data are given in table.1.

In tab. 2 shows the cleaning efficiency in the presence of metal-polymer complexes.

From .table 2, it follows that the most effective catalyst is a bivalent manganese polymer complex.

The limits of pH 7–10 are limited: the lower — by the dissociation constant of the amino-amino groups of the polymer, the upper by the instability of quinones in a strongly alkaline medium — which prevents their binding to the polymer.

The advantages of the process by the proposed method compared with the known are given in table. 3

Thus, the proposed method, compared with the known one, makes it possible to significantly simplify the process by eliminating the heating, neutralizing and water treatment stages with large amounts of metal salts, which cause an increase in the salinity and toxicity of the treated water, eliminating a special reactor for carrying out the purification process without reducing the degree of phenol purification.

Table 1

Claims (3)

1. METHOD OF PURIFICATION OF SEWAGE WATER FROM PHENOLS, including catalytic oxidation of the latter in the presence of transition metal compounds, characterized in that, in order to simplify the purification process, the oxidation is carried out with oxygen, and their complexes with polyethyleneimine are taken as transition metal compounds. 2. The method according to π. 1, characterized in that they use complexes of copper, cobalt, iron and manganese. 3. The method according to π. 1, characterized in that the oxidation is carried out at pH 7-10 S ω