The removal of some rare earth elements from their aqueous solutions on by-pass cement dust (BCD)

• Published in: Journal of hazardous materials 2011-11, Vol.195, p.62-67
• Main Authors: Ali, O.I.M., Osman, H.H., Sayed, S.A., Shalabi, M.E.H.
• Format: Article
• Language: English
• Subjects: Adsorption; Applied sciences; Aqueous solutions; BCD; cement; Cements; Chemical engineering; Dust; Endothermic reactions; Exact sciences and technology; gadolinium; Hydrogen-Ion Concentration; Kinetics; lutetium; Mathematical models; Metals, Rare Earth - isolation & purification; neodymium; Pollution; Rare earth elements; samarium; Solutions; Sorption; sorption isotherms; Surface Properties; temperature; Thermodynamics; Uptake; Water - chemistry; Yttrium
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2011.08.014

► Cement kiln dust (BCD) is an abundant and cheap waste that can be used to remove dangerous elements from aqueous solution. ► It can be used as an efficient sorbent for some rare earth elements (Y 3+, Nd 3+, Gd 3+, Sm 3+ and Lu 3+). ► The sorption of these elements follows pseudo-second-order kinetics. ► The sorption process is favorable and spontaneous. The sorption behavior of yttrium (Y 3+), neodymium (Nd 3+), gadolinium (Gd 3+), samarium (Sm 3+) and lutetium (Lu 3+) from their aqueous solutions by by-pass cement dust (BCD) has been investigated using a batch technique. The sorption on BCD was studied as a function of pH, shaking time, initial concentration, mass of BCD and temperature. It was found that the sorption capacity of BCD had the order of Lu 3+ > Sm 3+ > Y 3+ > Gd 3+ ≈ Nd 3+ following Freundlich isotherm at the determined optimum conditions. The results also demonstrated that the sorption data fit well the pseudo-second-order kinetic model. Thermodynamic parameters such as Δ H°, Δ S° and Δ G° indicated that the sorption of the investigated REEs on BCD was endothermic, favored at high temperature and spontaneous in nature.