Nanocomposites and nanomaterials

Nanostructured adsorbents for arsenic compounds removal
Gusak A.1, Litynska M.1, Krimets G.1, Dontsova T.1
1 Department of Technology of Inorganic Substances, Water Treatment and General Chemical Technology of National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute". Prospect Peremohy, 37, Kyiv-03056, Ukraine. 
E-mail: m.litynska-2017@kpi.ua

Increasing of arsenic content in natural waters due to changes of groundwater level and acidic rains is the significant problem of drinking water treatment. Arsenic is one of the most dangerous elements in world. According to European Commission, the maximum allowable level of arsenic in drinking water is 10 μg/l. High arsenic concentration in natural water is typical for India, China, Bangladesh, Taiwan, Vietnam, Hungary, USA, Mexico, Chile, Argentina, Hungary, Ghana, Iran, etc. [1-3]. Chronic arsenic exposure provokes a lot of different health problems, including cancer of skin and internal organs, endocrine disorders, hyperkeratosis, melanosis, etc. [2,4]. 
We synthesized nanostructured iron oxyhydroxide and iron oxyhydroxide/activated carbon adsorbents by homogeneous precipitation. We used thermal hydrolysis of urea to precipitate iron oxyhydroxide from iron(III) chloride solution. Obtained nanostructured adsorbents could be used for arsenic removal from water phase due to significant efficiency (the best sample efficiency is about 70 mg As/g). Modifying of activated carbon by iron oxyhydroxide improved the arsenic removal more than twice. So, these sorption materials are perspective for drinking water treatment.
 
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