Loading...
Removal of lead ions from wastewater using multi walled carbon nanotubes modified with sodium lauryl sulfate
Suliman, Malaz Ibrahim, Taleb Jumean, Fawwaz Khamis, Mustafa Sabri, Muhammad Ashraf
Suliman, Malaz
Ibrahim, Taleb
Jumean, Fawwaz
Khamis, Mustafa
Sabri, Muhammad Ashraf
Date
2017-12
Advisor
Type
Article
Degree
Description
Abstract
Multi walled carbon nanotubes (MWCNTs) modified with sodium lauryl sulfate (SLS) were synthe-sized, characterized and successfully used for the removal of Pb2+ from aqueous solutions. Adsorp-tion results revealed that this surface modification increased adsorption capacity from 3.84 to 141 mg/g. Adsorption on raw-MWCNTs followed the Langmuir isotherm with qm = 3.84 mg/g and KL = 0.29 L/mg, whereas adsorption on SLS-MWCNTs followed the Freundlich isotherm with n = 2.50 and KF = 15.40 mg 0.6·L0.4/g. Adsorption kinetics on raw and modified MWCNTs followed a pseudo second order law with rate constants 0.11 and 0.06 g/mg·min, respectively. Thermodynamic studies showed that Pb2+ was physisorbed on both adsorbents, with apparent Gibbs free energy, ∆G °,values of –0.45 and –9.21 kJ/mol at 25°C, respectively. Magnetite derivatives of SLS-MWCNTs were synthesized and used for Pb2+ removal. Batch adsorption studies on the magnetite and non-magnetite SLS-MWCNTs gave similar results. The enhanced density of the magnetite pellets of SLS-MWCNTs allowed for their use in a packed bed column. Column operation modeling results showed that the modified dose response model most adequately describes the column data with parameter values qmdr = 28.4 mg/g and a’ = 3.47 mg–1.