Functionalized carbon nanotubes based filters for chromium removal from aqueous solutions.

This investigation examines the filtration efficiency of chromium from aqueous solution using two types of commercial multiwalled carbon nanotubes (MWCNTs) (Taunit-M (TM) and Taunit-MD (TMD)). These MWCNTs were modified using two complementary treatments, purification (using a mixture of hydrochloric acid and hydrogen peroxide) and functionalization (using nitric acid). The effect of these treatments on the morphology of MWCNT Taunit filters was characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy to estimate the outer diameter distribution and element content deposited on filters.