Efficacy of single-walled carbon nanotubes on adsorption of Reactive Red 198 from aqueous solutions

colors make many problems and these are major sources of environmental pollution. Therefore, this wastewater should be treated before discharge to environment to reduce the environmental threats. Adsorption is one of the usual processes for color removal from wastewater. Nanotubes are new adsorbents with extend application for adsorption of different compounds. Aim of this study was survey on feasibility of single-walled carbon Nanotubes as adsorbent to reactive red 198 dye adsorption from aqueous solutions. This study was done in a batch reactor. The effects of various parameters such as contact time mixing intensity, initial dye concentration, pH and single-walled carbon Nanotubes dose on removal of Reactive Red 198 color was investigated. The results showed the optimal time for achieve to maximum adsorption and equilibrium is 3 hours. More increasing in adsorbent dose from 0.1 to 0.9 g, more increasing in dye removal efficiency from 91.8% to 100%. It was found that the maximum adsorption capacity of reactive red 198 on single-walled carbon nanotubes was 7.98 mg/gr and it was occurred in acidic condition (pH = 4). Decreasing in initial dye concentration from 50 to 25 mg/l in pH 4 and during 3 hours can cause increasing in removal efficiency from 9/96% to 100%. The results showed reaction kinetic was described by Pseudo-first order equation and adsorption isotherm was followed both Freundlich and Langmuir isotherm models. Due to the small size, high surface area, crystalline shape and unique regularity of the network, the reactivity of single-walled carbon Nanotubes is very high. Single-walled carbon nanotubes have impressive performance as adsorbents to removal of reactive red dye 198.