Zeolitisation of Neogene sedimentary and pyroclastic rocks exposed in Paipa (Boyacá), in the Colombian Andes: simulating their natural formation conditions

Abstract

The present study concerns the synthesis of zeolites from Neogene sedimentary and pyroclastic rocks exposed around the Sochagota Lake, Paipa (Boyacá). Two synthesis methods were used: conventional hydrothermal treatment and alkaline fusion followed by hydrothermal reaction. Both raw materials and synthesised zeolytic products were characterised by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). Several zeolytic phases were synthesised, including faujasite (FAU), phillipsite(PHI) and sodalite (SOD). The results showed that the alkaline fusion approach was more efficient regarding hydrothermal conversion of the raw materials than conventional hydrothermal treatment, taking into accountthat zeolytic products having a higher degree of crystallinity and few impurities were obtained in this way. This study was aimed at applying experimental mineralogy to a laboratory simulation of the geological conditions in which zeolites can occur as the basis for defining criteria for exploring natural zeolites in Colombia, with prospects for the profitable exploitation of these mineral resources in different parts of Colombia