SU1583361A1 - Method of purifying waste water from leukanol - Google Patents

Abstract

The invention relates to the protection of the environment from harmful emissions into water bodies and can be used to treat industrial wastewater from biologically "hard" compounds, in particular leukanol. The purpose of the invention is to increase the degree of purification. Water purification is performed by passing it through an electrolyzer without diaphragm with insoluble anodes of the ORTA type (coating composition, mol.%: TIO 2 65-70

RUO 2 30-35) at a current density of 0.5-2.5 A / dm 2 and PH 1-2.

Description

The invention relates to the protection of the environment from harmful emissions into water bodies and can be used to purify industrial wastewater from biologically rigid compounds, in particular leukanol.

The purpose of the invention is to increase the degree of purification of wastewater containing leukanol.

When it is molar 1. A model solution prepared on tap water and containing 300 mg / l of leukanol, 30 g / l of sodium chloride, 0.5 g / l of sodium sulfate is used as the water to be purified. The content of leukanol and sodium chloride corresponds to their concentration in serum, resulting in the production of nitrile rubbers.

For carrying out the electrochemical decomposition of leukanol, 800 cm3 of waste water are placed in a diaphragm-free

A 900 cm rectangular shaped electrolyzer made of plexiglass with a magnetic stir bar in the bottom and a water cooling jacket. A pack of rectangular electrodes (two anodes and three cathodes) with a fixed distance between them of 10 mm is placed in the electrolyzer. The anodes are made of titanium and coated with a layer of a mixture of titanium oxides and ruthenium of composition, mol%: TiOi 70; KiOg 30, the cathodes are made of titanium. The temperature at which lead electrolysis, / / 25 ° C. Samples for analysis are taken at regular intervals.

The anodic current density is 0.5 A / dm, pH 2. The electrolysis time is 25 min, the leukanol content in the electrolyzate is 12 mg / l. The electrolysis time is 30 min, the content of leukanol is 0 mg / l.

(L

with

ate

00 CO 00 G &

The content of peicanol is determined spectrophotometrically with a length of

waves 228 nm.

Example 2. Electrolysis is carried out analogously to example 1. The composition of the anode, mol%: TiO 65; RuOt 35. Anodic current density 2.5 A / dm, pH 2. Electrolysis time 15 min, leukanol content in electrolysate 25 mg / l. The electrolysis time is 20 min, the content of leukanol is 0 mg / l.

Example 3. Electrolysis of the wire | t is similar to Example 1 and with the same anode. Anodic current density 0.5 A / dm, pH 1, electrolysis time 20 min, leukanol content in the electrolyzate 15 mg / l, electrolysis time 25 min, leukanol content in the electrolyte 0 mg / l,

i

Example 4. Electrolysis is carried out analogously to example 1 and with the same anode. The anodic current density is A / dm2-, pH 1. The electrolysis time is 10 min, the leukanol content in the electrolyte is 32 mg / l, the electrolysis time is 15 min, the leukanol content in the electrolyzate is 0 mg / l.

Example 5. The electrolysis is carried out as in Example 1 and with the anode. The anodic current density is 0.3 A / dm2, pH 1. The electrolysis time is 20 min, the leukanol content in the electrolyzate is 168 mg / l, the electrolysis time is 25 min, the leukanol content in the extract | roller is 84 mg / l.

Example 6. Electrolysis is carried out analogously to example 1 and with the same anode with anodic current density of 3.0 A / dm, pH 1. Electrolysis time is 10 min, leukanol content in the electrolyzate is 25 mg / l, electrolysis time is 15 min, leukanol content is electrolyzate 0 mg / l,

Example 7. Electrolysis was carried out as in Example 1 and with the same anode. The anodic current density is 2.5 A / dm1, pH 3. The electrolysis time is 10 min, the leukanol content in the electrolyzate is 223 mg / l, the electrolysis time is 15 min, the leukanol content in the electrolyzate is 190 mg / l.

As follows from the data presented, at a pH of more than 2, the speed of the process decreases sharply, which leads to a decrease in the productivity of the electrolyzer and an increase in energy consumption. At a pH of less than 1, the acid consumption increases without significantly increasing the speed of the process. With

current density less than 0.5 A / dm. destruction of leukanol occurs very slowly, its increase (more than 2.5 A / dm2) does not lead to a significant increase in the process speed, but

a sharp increase in foaming and an electrolyte release from the electrode zone are observed, which leads to a decrease in the degree of purification.

The composition of the anodic coating is chosen

Q outcome of the conditions of work. When the RuOz content is less than 30 mol.%, The anode activity decreases, which deteriorates the process performance. An increase in Ru02 (more than 35%) does not affect

5 anode activity.

When water is purified by a known method, up to 6 mg / l of leukanol remains in purified water. Since the MPL of leukanol is 0.25 mg / l, such water cannot be discharged

0

five

in the reservoirs, and the full use of this water as recycling will lead to the accumulation of leukanol in it and will require additional purification. The application of the proposed method allows to completely purify water from leukanol.

Claims (1)

Invention Formula 0 The method of wastewater treatment from leukanol, including their electrochemical treatment, characterized in that, in order to increase the degree of wastewater treatment, the electrochemical treatment is carried out in a diaphragm-free electrolyzer using titanium anodes coated with a titanium layer and ruthenium composition, mol. %: 0 RuO-, TiOa I 1 0.5-2.5 A / dm. 30-35 65-70 at pH 1-2 and anodic current density