Abstract Single-walled Carbon Nanotubes (SWCNTs) used as absorbents to remove Acid Red 88 (AR88) dyes from wastewater have been investigated here because they are effective in removing organic pollutants. The adsorption process was affected by various experimental conditions such as pH, contact time and biosorbent concentration. Maximum dye removal was observed at pH 3 and 0.25 g/L o biosorbent concentration. Adsorption equilibrium was established in 75 min. Experimental data were fitted well to the Langmuir isotherm model. The maximum dye removal percentage was determined as 97.5%. The negative values of free-energy change confirmed the feasibility of the process and the spontaneous nature of adsorption. Furthermore, from the magnitude of ΔH, the process was found to be endothermic physisorption.