RECYCLING OF LITHIUM-CONTAINING CHEMICAL CURRENT SOURCES USING BAROMEMBRANE TECHOLOGY

ПЕРЕРАБОТКА ЛИТИЙСОДЕРЖАЩИХ ХИМИЧЕСКИХ ИСТОЧНИКОВ ТОКА С ИСПОЛЬЗОВАНИЕМ БАРОМЕМБРАННОЙ ТЕХНОЛОГИИ

Козловский Николай Алексеевич

студент Московского Политехнического Университета, РФ, г. Москва

Кожухова Валентина Валерьевна

 старший преподаватель кафедры «Иностранные языки» Московского политехнического университета, учитель ГБОУ «Школа № 2103», заместитель директора АНО ДПО «Восточно-Сибирский образовательный центр», РФ, г. Москва

Abstract. The article is devoted to the study of recycling of chemical current sources in Russia and consideration of problems in this area. The existing processing schemes and their problems of extracting valuable components are considered. A scheme is also proposed to increase the number of extracted valuable components.

Аннотация. Статья посвящена изучению рециклинга химических источников тока в России и рассмотрению проблем в этой области. Рассмотрены существующие схемы переработки и связанные с ними проблемы извлечения ценных компонентов. Также предложена схема увеличения количества извлекаемых ценных компонентов.

Keywords: chemical current sources, recycling, utilization, baromembrane technologies, lithium, cobalt.

Ключевые слова: химические источники тока, рециклинг, утилизация, баромембранные технологии, литий, кобальт.

An urgent problem today is the disposal of batteries and accumulators. The optimal technology for handling them has not yet been created. Most often they are stored and buried, which leads to environmental pollution. However, the spent current sources contain many valuable components that are secondary material resources.

Nowadays it is difficult to imagine any activity without batteries and accumulators or, in other words, chemical current sources (CCS). They are an integral part of our daily life – phones, tablets, laptops, and are also used in all spheres of activity. However, CCS requires recycling, since they consist of elements that, when extracted from the used CCS, can be sent for secondary use. Otherwise, if the substance is improperly disposed of, it will not only be impossible to send it for reuse, but also irreparable damage to the environment will be caused, since the elements contained in the CCS are very toxic.

There is recycling of secondary components of nickel-containing batteries, but this process is not economically profitable, since the amount of money invested in the extraction of these components will exceed the amount of funds raised from sales. The situation is further aggravated by the fact that there are a large number of supplies of raw materials on the market. The problem also concerns other types of batteries, except for those that use lithium, but for this type of current source in our country has not yet been developed.

It is worth noting that the country is engaged in the purchase of lithium carbonate from other countries, but sells lithium hydroxide and chloride [1], and the development of this process is able to establish domestic production and increase the number of exported elements.

Lithium carbonate is used in various industries, so, for example, this compound increases the melting efficiency of glass and reduces the thermal conductivity of ceramics [2]. Lithium and lithium hydroxide are mainly used in the manufacture of lithium batteries themselves. In addition, the lithium hydroxide compound is used, for example, in gas masks, where it neutralizes CO2, in the production of refrigeration units, in radio engineering and electronics.

Below is the percentage of chemicals in the composition of chemical current sources [3-5]:

Table 1.

Percentage of chemicals in CCS

According to the data given above, it can be seen that lithium-ion batteries contain a considerable part of cobalt, compared with other CCS. This chemical element does not pose a particular danger in the form of a piece of metal, but its compounds are dangerous because some of them have a low lethal dose for living organisms. In addition, these batteries have a more toxic electrolyte, lithium salt, which, when in contact with a small amount of moisture, decomposes with the release of hydrofluoric acid, which is very dangerous. In addition, the lithium salt used has carcinogenic activity.

Currently, an electrolyte is used in CCS, which includes one of the lithium salts - LiPF₆, LiCI₄, LiAsF₄, LiBF₄. These salts are toxic, therefore, it is necessary to ensure maximum extraction of lithium from the composition of CCS. This will reduce the negative impact on the environment and increase the economic component of production [6].

The currently existing schemes for processing lithium batteries and accumulators have similar stages of the processing and disposal process, such as crushing, grinding and separation of valuable components, however, all these schemes have a common disadvantage, namely, a low percentage of extraction of target products from various components of the CCS.

The problem of a low percentage of extraction is that the existing technological schemes for extracting valuable components from CCS are limited only to leaching and precipitation, but baromembrane methods can increase the percentage of extraction from solutions of the necessary components.

The resulting solutions, after leaching, can be sent first to the ultrafiltration stage in order to delay high-molecular substances, and then to the reverse osmosis stage to separate the solution of low-molecular substances and salts, thereby increasing the degree of extraction.

It can be concluded that there are 2 main problems of CCS recycling: a low percentage of extraction of valuable components and the absence of a completely environmentally friendly technology, since all processes take place with the release of harmful gases or the formation of dust, including metal. Nevertheless, with the help of baromembrane technologies, it is possible to at least increase the percentage of extraction of valuable components from spent current sources.