Interaction of Pb2+ ions with surfactant-containing mesoporous silicates

In this study, the interaction between surfactant-containing mesoporous silicates and Pb2+ ions in water was investigated through adsorption tests and characterizations. The mesoporous silicates containing dodecylamine as the surfactant showed a Pb2+ adsorption capacity of 198.6 mg g−1, a value obtained from the fit of the adsorption isotherm to the Langmuir model. X-ray diffraction patterns revealed that the intensity of the main peak for the mesoporous silicates decreased after the adsorption test, implying that Pb2+ ions attached to dodecylamine. Scanning electron microscopy images of the adsorbent before and after Pb2+ adsorption indicated that there was no morphological change in the mesoporous silicate. When comparing FT-IR patterns for the adsorbent before and after Pb2+ adsorption, a new IR band was observed at 1394 cm−1 after Pb2+ adsorption, which proved that coordination bonding occurs between Pb2+ ions and amino groups in the surfactant.