Application of carbon nanotubes in filters and membranes for wastewater treatment

Odpadna voda je voda, ki nastane po uporabi sladke, surove, pitne ali slane vode v različnih namenskih aplikacijah ali procesih. V grobem lahko odpadne vode delimo na tri glavne tipe: komunalne oz. gospodinjske odpadne vode, industrijske odpadne vode in meteorne oz. padavinske odpadne vode. Pri onesnaževalih v odpadnih, ki prihajajo iz različnih virov, gre za naravna onesnaževala ali sintetična onesnaževala. Kadar je voda onesnažena in je potrebno dekontaminiranje, je treba izbrati najboljši pristop čiščenja, da se dosežejo cilji dekontaminacije. Pri tem se uporabljajo različni postopki in tehnike. Membranska filtracija postaja pogosta tehnika za doseganje primerne kvalitete vode. Uporaba ogljikovih nanocevk pri tem kaže velik potencial zaradi kemije površine, morfologije, kemijske in fizikalne interakcije z organskimi in anorganskimi snovmi, dobrih adsorpcijskih lastnosti in številnih možnosti funkcionalizacije oz. modifikacije. V študijah so že razvili različne membranske filtre za praktično uporabo in z njimi dokazali njihovo visoko učinkovitost. Med najučinkovitejše spada elektrokemijski filter narejen iz skupkov ogljikovih nanocevk sklopljen z in situ generacijo H2O2. Kljub temu pa visoka cena materiala, zamašitve filtra in ekološka problematika ogljikovih nanocevk predstavljajo problem za vsakdanjo uporabo pri čiščenju odpadnih vod. V ta namen bi bilo potrebno narediti več študij, predvsem na večji skali.Wastewater is water that is produced after fresh, raw, drinkable, or saline water has been used in various applications or processes. Roughly speaking, wastewater can be divided into three main types: municipal or domestic wastewater, industrial wastewater and stormwater or precipitation wastewater. The pollutants in wastewater come from a variety of sources, either natural pollutants or synthetic pollutants. When water is contaminated and decontamination is necessary, the best treatment approach must be chosen to achieve the decontamination objectives. Different processes and techniques are used. Membrane filtration is becoming a common technique to achieve adequate water quality. The use of carbon nanotubes in this context shows great potential due to their surface chemistry, morphology, chemical and physical interaction with organic and inorganic substances, good adsorption properties and many possibilities for functionalisation or modification. Various membrane filters have already been developed for practical applications and their high efficiency has been demonstrated in studies. Among the most effective is an electrochemical filter made of carbon nanotube clusters coupled with in situ generation of H2O2. However, the high cost of the material, the fouling of the filter and the ecological problems of carbon nanotubes are a challenge for everyday use in wastewater treatment. More studies should be carried out for this purpose, especially on a larger scale