Modificación de la química superficial del hueso de nanche para aumentar su capacidad de biosorción de pb2+

Bernal-Jácome Luis Armando, Olvera-Izaguirre Lizeth, Gallegos-García Marisol, Espinosa-Rodríguez Miguel Ángel
CiBiT, 32(11) pp 35-39., 2016.


The biosorption capacity of Pb (II) present in aqueous solution with natural and modified nanche stone was evaluated. The surface chemistry of nanche stone was modified with citric acid 1M. The characterization of natural and modified stone involved the determination of point of zero charge (PHPZC), determination of active sites by the Boehm method and FTIR characterization, and the development of mathematical models through isotherms to determine its adsorption capacity. The PHPZC for natural and modified stone was in an acid range. The concentration of acid sites of natural stone were of 0.1037 to 0.1081 mol/g and for the modified of 0.1053 to 0.1123 mol/g. The infrared spectra (FTIR) detected the formation of acid sites through the formation of oxygen and hydrogen complexes on the surface of the precursor. The biosorption capacity of Pb (II) with natural and modified stone, increased with increasing the initial concentration of the solution with lead (Ci) to pH 4. For example, for a Ci 108.6 mg/L, pH 4 and 25 °C, 69% removal of lead with natural stone was obtained, while with the modified is increased to 97%.