Sorção de chumbo numa sílica modificada obtida da crisotila: aplicação de isotermas.

A silica was modified with three alcoxysilanes with different quantities of nitrogen, whose the silica obtained from chrysotile acid leaching. The modified silicas were applied in lead removal from aqueous solution, obtained the following capacities: 1.41, 0.78 e 0.60 mmol g-1 for the materials containing 3, 1 and 2 nitrogen in organic chains, respectively. The isotherms were adjusted using different models, and each material showed affinity to a model. The interactions were favorable and spontaneous from Freundlich model and Gibbs free energy, respectively. [ABSTRACT FROM AUTHOR]