SU150825A1

SU150825A1 - Electrolyzer for high purity alkali

Info

Publication number: SU150825A1
Application number: SU724591A
Authority: SU
Inventors: В.П. Чвирук
Original assignee: В. П. Чвирук
Priority date: 1961-04-03
Filing date: 1961-04-03
Publication date: 1977-03-05

Description

Известно получение и рафинирование металлов и их соединений, в частности щелочей, методом электролиза с получением амальгам и последующим их разложением.It is known to obtain and refine metals and their compounds, in particular alkalis, by electrolysis method to produce amalgams and their subsequent decomposition.

Известны также электролизеры дл рафииирозани металлов, состо щие из нескольких электролитических чеек, соединенных между собой бипол рными ама.тьгамными электродами , однако в них не достигаетс высокого рафинировочного эффекта и не совмещены рафинирование и разложение амальгамы.Electrolyzers for refining of metals are also known, consisting of several electrolytic cells interconnected by bipolar am-phamic electrodes, but they do not achieve a high refining effect and the amalgam is not combined.

Предлагаемый электролизер дл получени щелочей высокой чистоты отличаетс от известных тем, что в нем применены пленочные бипол рные электроды, расположенные друг над другом, верхний из которых снабжен графитовой иасадкой. Благодар такой конструкции достигаетс высокий рафинировочный эффект и совмещаютс рафинирование и разложение амальгамы.The proposed electrolyzer for producing high-purity alkalis differs from the known ones in that it uses film bipolar electrodes located one above the other, the top one of which is equipped with a graphite i-pad. Due to this construction, a high refining effect is achieved and the amalgam refining and decomposition are combined.

На чертеже изображена принципиальна схема предлагаемого электролизера.The drawing shows a schematic diagram of the proposed electrolyzer.

Амальгама натри , поступающа в нижнюю часть / электролизера, с помощью контактов 2 электрически св зана с положительным полюсом источника посто нпого тока. Над амальгамой натри расположены друг над другом пленочные амальгамные бипол рные электроды 3, количество которых соответствует числу ступеней рафинировани . Опорои дл этих электродов служит соответствующа диафрагмеппа ткань. На последнем электроде находитс графитова насадка 4, на которой происходит процесс разложени The sodium amalgam entering the bottom / electrolyzer is electrically connected to the positive pole of the direct current source through contacts 2. Above the sodium amalgam, film amalgam bipolar electrodes 3 are located one above the other, the number of which corresponds to the number of refining stages. The support for these electrodes is the tissue that is appropriate for the diaphragm. On the last electrode there is a graphite nozzle 4, on which the decomposition process takes place.

амальгамы натри . Одновременно графитова насадка может быть использована в качестве контакта 5 дл нодключени отрицательного полюса источника посто нного тока. Промежутки 6 между электродами заполнены раствором едкого натра, который вл етс рафинировочным электролитом.sodium amalgam. At the same time, a graphite nozzle can be used as a contact 5 to connect the negative pole of the DC source. The gaps 6 between the electrodes are filled with sodium hydroxide solution, which is a refining electrolyte.

Если на электродах имеетс амальгама натри , то при подключении посто нного тока к электролизеру начнетс рафинирование патри . Натрий будет ионизироватьс на амальгаме натри нижней части 1 электролизера, разр жатьс на нижней стороне первого электрода , котора вл етс амальгамным катодом , диффундировать через слой ртути, ионизироватьс на верхней части электрода - амальгамном аноде и т. д. На верхнем электроде будет идти процесс разложени амальгамы натри на графитовой насадке подаваемой чистой водой с образованием чистой щелочи и водорода.If sodium amalgam is present on the electrodes, then when the direct current is connected to the electrolyzer, a refining pat will begin. Sodium will ionize on the sodium amalgam of the lower part 1 of the electrolyzer, discharge on the lower side of the first electrode, which is the amalgam cathode, diffuse through the mercury layer, ionize on the upper part of the electrode — an amalgam anode, etc. sodium amalgam on a graphite nozzle supplied with clean water to form pure alkali and hydrogen.

Claims

Due to the fact that the cathode current output at each electrode is 100%, which is due to the spontaneous decomposition of sodium amalgam, it is necessary to somehow compensate for the difference in the anode and cathode outputs but to avoid oxidation of mercury on the anode side of the bipolar electrode. In addition, the gradual contamination of sodium amalgam and the refining electrolyte with impurities of various metals will take place in the process of the operation of the electrolyzer. Compensating for differences in current output and updating sodium amalgam to cleaner cleaner is as follows. In the upper part of the electrolyzer, where the sodium amalgam decomposes, the mercury is cleaned, and the sodium amalgam in an amount corresponding to the volume of mercury supplied goes through the overflow 7 to the adjacent lower electrode, etc., as shown in the diagram. Thus, sodium amalgam coming from the upper to the lower electrodes compensates for the amount of sodium that has decomposed due to the spontaneous breaking of the sodium amalgam and simultaneously updates the electrode amalgam to a cleaner one. At the same time, the amount of sodium amalgam coming from the upper electrode should be sufficient to compensate for the difference in current output across all electrodes. From the last electrode, sodium amalgam is either fed to the mercury purification plant, or shifted with sodium amalgam from the electrolyzer, and from there weak sodium amalgam is taken in the same quantities to the mercury purification plant. Part of the pure caustic soda obtained by the top 3 compartments of the electrolyzer, overflow 7, also comes under the last electrode. Pure water is also supplied to dilute the incoming caustic soda to the required concentration. The electrolyte, after successive passage of all the spaces between the electrodes, is drawn along the clamp 8 from the lower part in the form of caustic soda of low quality. In order to avoid the formation of hydrogen released by the self-decomposing of sodium amalgam, gas pods under the electrodes, gas vents 9 are needed. Thus, a thin layer of mercury, on which sodium refining occurs, works as an amalgam bipolar electrode, the lower part is the cathode, and the anode. Studies have shown that with an electrode film thickness of 5 mm, the process can be conducted at a current density of 8-10 ka / m. An electrolyzer for producing high purity alkalis by refining metals, consisting of refining cells formed by bipolar electrodes, characterized in that, in order to achieve a high refining effect and to combine the refining and decomposition of amalgam, film bipers are used in the electrolyzer. above the other, the top of which is equipped with a graphite nozzle. one