Ciprofloxacin hydrochloride is an important pharmaceutical ingredient. It is used for many bacterial infection treatment. It can present in water sources due to incomplete metabolism in humans and coming from the pharmaceutical factory effluents. In this work, the adsorption of ciprofloxacin hydrochloride by multiwall carbon nanotube (MWCNT) was investigated. The effects of equilibrium of adsorption time and initial ciprofloxacin hydrochloride concentration on adsorption were determined. Langmuir and Freundlich isotherm models were utilized to express to the adsorption mechanism of ciprofloxacin hydrochloride by MWCNT. In addition, pseudo-first order, pseudo-second order and Elovich kinetic models were applied. This study showed that MWCNT absorbent is highly effective adsorbent for the removal of ciprofloxacin hydrochloride from aqueous solutions. Equilibrium data for adsorption of ciprofloxacin hydrochloride on MWCNT were best exemplified by Freundlich isotherm with a value of R square 0.9993. The most favorable kinetic model was obtained as pseudo-second order kinetic model with a value of R square 1.000. (C) 2020 Elsevier B.V. All rights reserved.