US EPA

4191251 

Journal Article 

Uptake of mercury (II) in batch system by stannic-titania mixed-oxide gel: Kinetics and thermodynamics 

Thomas, R; Anirudhan, TS 

1999 

Yes 

Indian Journal of Chemical Technology
ISSN: 0971-457X 

6 

5 

268-275 

WOS:000083920600005 

Relatively limited information is available regarding the kinetics of sorption of metal ions from solutions onto mixed-oxide gel. For this reason, a detailed study of the kinetics of sorption of Hg(II) on stannic-titania mixed-oxide gel was conducted in a controlled batch system. The sorbent has the ability to adsorb substantial quantities of Hg(II) from aqueous solutions. The extent of removal was found to be dependent on adsorbent dose, initial concentration, pH and temperature. The process follows first-order reversible kinetics. The intraparticle diffusion of metal ions through pores in the adsorbent was shown to be the main rate limiting step. Adsorbent is effective for the quantitative removal of Hg(II) over the pH range 5-10. The applicability of Langmuir adsorption isotherm equation for Hg(II) removal has been tested. An examination of thermodynamic parameters shows that the adsorption of Hg(II) by adsorbent is an endothermic process and is spontaneous at the temperature investigated. The method was applied for synthetic wastewater. The spent gel can be regenerated and reused by HCl treatment.