The survey of application of the linear and nonlinear kinetic models for the adsorption of nickel(II) by modified multi-walled carbon nanotubes

Abstract

Pollution due to the presence of nickel is of great importance because of its toxic nature and non-biodegradability. Nickel is one of the most common heavy metals used in the industry. The purpose of the study is to investigate the efficiency of modified multi-walled carbon nanotubes (MWCNTs) on the adsorptive removal of nickel (II) from its aqueous environment and also to survey the applicability of the linear and nonlinear adsorption kinetic models on the process. The effects of process parameters including pH (4, 5, 7, and 10), MWCNT dosage (2.5, 5, 10, and 12 mg/L), initial nickel (II) ion concentration (25, 50, 100, and 125 mg/L) and contact time (5, 10, 25, and 40 min) on the removal efficiency of nickel using MWCNTs were studied, and their optimum conditions were also determined. Maximum nickel removal efficiency of 82% was observed at the optimum conditions of pH 10, MWCNT dosage of 10mg/L, initial nickel concentration of 100 mg/L and contact time of 10 min. The experimental data fitted best into the linear Ho (I) kinetic models than the other linear models. The ratedetermining step of the process was found to be chemisorption. The correlation coefficient R 2 values obtained for the linear and nonlinear models revealed that the nonlinear Ho adsorption kinetic provided a better explanation of the adsorption kinetic data of nickel removal by MWCNTs.

Sensitivity Analysis with the Monte Carlo Method and Prediction of Atenolol Removal Using Modified Multiwalled Carbon Nanotubes Based on the Response Surface Method: Isotherm and Kinetics Studies

“…Ahmadi et al reported that the optimal pH for Ni (II) ions adsorption on MWCNTs from aqueous solution is 10. ey mentioned that it could be attributed to the surface of the MWCNTs and is negatively charged. pH and the Ni (II) ions are positively charged; thus, electrostatic attraction is increased between them which enhanced the removal efficiency [38].…”

Kinetic Studies on Penicillin G Removal from Aqueous Environments by Cupric Oxide Nanoparticles

“…The increased rate of removal efficiency at pH of 6 is related to the point of zero charge and pKa of the CuO-NPs and PG, respectively. The point of zero charge is defined as the pH at which the net charge of the total particle surface is equal to zero (25). The PG pKa was reported as 2.75, and the pHzpc of CuO-NPs was equal to 9.4.…”

“…This can be attributed to the increase in adsorption sites with more nanoparticles resulting in a marked increase in adsorption capacity (33). The decrease in the adsorption capacity is also ascribed to active adsorption sites which are unsaturated during the process of PG removal on CuO-NPs (25,34).…”

Amino-Thiol Bifunctional Polysilsesquioxane/Carbon Nanotubes Magnetic Composites as Adsorbents for Hg(II) Removal

“…Carbon nanotubes (CNTs) are one novel nano-adsorbent used in water pollution treatment over the past decades (Alimohammady et al, 2017;Ahmadi et al, 2019). Compared to zeolite, kaolinite, chitosan, biopolymer, and other traditional adsorption materials (Zhang M. et al, 2019;Fu et al, 2021;Khan et al, 2021), CNTs have more excellent aspect ratio, specific surface area, and unique one-dimensional structure (Sone et al, 2008;Aliyu, 2019), and all these structural features provide convenient conditions for metal ions adhering.…”