Experimental investigation of the capacity of carbon nanotubes to absorb organic pollutants

Abstract

Abstract Dissolved organic pollutants caused by paints, detergents, herbicides, and toxins cannot be removed from the water body through conventional treatment processes such as filtration. Activated carbon is one of the effective substances to obliterate these contaminants from water. The carbon nanotubes (CNTs) have a much higher ability to decompose organic pollutants; however, using the slurry form is undesirable due to the removal requirement at the end of the treatment process. In the present study, upgraded CNTs attached to particles of sand filters (CNTsand) were synthesized and applied to omit dissolved organic pollutants. The results revealed the high capacity of the CNTsand to wipe organic contaminants. The column test with natural water compared to the synthesized 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. Finally, the adequacy and efficiency of the upgraded nanotube coating on sand grains to remove organic pollutants were confirmed.