Enhancing adsorption capacity of carbon nanotubes through sand filters for the removal of organic pollutants: a column investigation.

Abstract

Dissolved organic pollutants caused by paints, detergents, herbicides, and toxins cannot be removed by conventional water treatment processes such as filtration. Different figures of activated carbon such as carbon nanotubes (CNTs) are substances to obliterate these contaminants. Although these CNTs have higher ability to decompose organic contaminants, using the slurry form of CNTs is not suitable due to the removal requirement at the end of the treatment procedure. In this study, upgraded CNTs attached to particles of sand filters (CNT_sand) were synthesised and applied to remove dissolved organic pollutants. The results revealed the high capacity of the CNT_sand to extract organic contaminants. The column test with natural water compared to the distilled water had a more extended breakpoint, higher adsorption capacity, and consequently, further removal efficiency, such that for the surface area loading rate of 4.8 ml/min, the breakpoint increased from 739 minutes to 936 minutes as well as the volume of passed water grew from 3546 ml to 4493 ml; Therefore, the maximum adsorption capacity was enhanced from 67.3 mg/g to 89.5 mg/g. In conclusion, the adequacy and efficiency of the upgraded nanotube coating on sand grains to remove organic pollutants were confirmed.