Removal of cadmium and humic acid from aqueous solutions using surface modified nanozeolite A

Abstract

ABSTRACT:The sorption of cadmium and humic acids from aqueous solutions using surface-modified nanozeolite A has been investigated under various examination conditions. The morphology of untreated and treated nanozeolite was studied under scanning electron microscope and transmission electron microscope. Isotherms of cadmium adsorption onto surfacemodified nanozeolite A were studied at different pH, solid to liquid ratio, adsorbate concentration and interaction time. Kinetic and equilibrium studies were conducted and the equilibrium data have been analyzed using Langmuir and Freundlich isotherm models. The study revealed that experimental results were in agreement with the Freundlich model. The Langmuir monolayer adsorption capacity was found to be 1666.67 g cadmium and 6.75 g humic acid per gram of modified nanozeolite A, which is higher than that of reported value for other zeolites. The sorption ability was enhanced by surface modification and reduction in size and enabled the zeolite to adsorb cadmium. The adsorption of cadmium and humic acid on nanozeolite was found to be the highest at pH 6 and 3, respectively. Results showed that solid to liquid ratio and pH are the most important factors for cadmium and humic acid removal, respectively. Effect of competitive ions was studied and results showed that there is no competition between cadmium and humic acid sorption and presence of these ions.

Kinetics and thermodynamics of cadmium ion removal by adsorption onto nano zerovalent iron particles

“…A variety of adsorbents, including clays, zeolites, dried plant parts, agricultural waste biomass, biopolymers, metal oxides, microorganisms, sewage sludge, fly ash and activated carbon have been used for cadmium removal [2,[7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Nano zerovalent iron (nZVI), an emerging technology, is being used to successfully treat various metallic ions in aqueous solutions (e.g., Cr 6+ , Cu 2+ , Pb 2+ , Ba 2+ , As 3+ , As 5+ , and Co 2+ ) [21][22][23][24][25].…”

A Review on Cr(VI) Adsorption Using Inorganic Materials

“…Zeolites can be treated with cationic surfactants in order to do this. Through treatment, an organic layer is created on the external surfaces and the charge is reversed to positive [20]. These cationic surfactants increase the fractional organic carbon content in order to enhance the sorption of non-polar hydrophobic organic contaminants.…”

Removal of Cr(VI) Species from Aqueous Solution by Different Nanoporous Materials

“…Removal of toxic metals from sewage and wastewaters [1][2][3][4][5][6][7][8][9][10][11][12] is a must from eco-friendly, health, and even economic points of view. Heavy metals are defined as elements with atomic weights of 63-200 and a specific gravity larger than 5 [11].…”