Especiação e quimissorção de Pb(II) em rejeito de caulim Speciation and chemisorption of Pb(II) on kaolin waste
oleh: Marta Helena Tavares Pinheiro, Vanda Porpino Lemos, Kelly das G. Fernandes Dantas, Taynara Lima Valentim
| Format: | Article |
|---|---|
| Diterbitkan: | Sociedade Brasileira de Química 2013-01-01 |
Deskripsi
<abstract language="eng">This study assesses the adsorption of Pb(II) on natural kaolin waste (KRnatural) and on that treated with 3 mol L-1 H2SO4 and HCl. Equilibrium and thermodynamic parameters were determined. The results indicate that the values of CEC, specific area and SiO2/Al2O3 ratio (4.6-6.0 cmol kg-1, 14.0-16.0 m² g-1 and 1.16-1.30, respectively) vary only slightly for the adsorbents; the concentration of Pb2+ is much higher than that of other species (PbOH+ and Pb(OH)2). The values of R L, ΔGº, ΔHº and ΔSº are typical of feasible, spontaneous, exothermic and ordered adsorption. The chemisorption on KRnatural is more feasible and ordered.