TRANSFORMATION OF INDONESIAN NATURAL CRYSTALLINE ALUMINOSILICATE MATERIAL TO SEVERAL TYPES OF ZEOLITE

• Main Author: Alvin Setiadi, Giovanno
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/55000
• Institution: Institut Teknologi Bandung

Historically, the archipelago of Indonesia has the greatest number of active volcanic sites. This geographic condition originates Indonesia to be one of the countries with massive natural zeolite deposits. X-Ray Diffraction (XRD) and X-Ray Fluorescence characterization on natural minerals from Messawa presented high crystallinity and chemical composition of aluminosilicates. However, the specific topology of the sample could not be identified. Several previous studies have shown the potential of even low-quality natural minerals as precursors or seeds in the hydrothermal synthesis of zeolites. The utilization of natural aluminosilicate material will be more favorable if the topology or even at the bare minimum level, the zeolite fragmentation contained in the sample is known. In this experiment, the natural aluminosilicate material was studied by recrystallizing and using it as a seed. The transformation of natural minerals into zeolites is expected to unveil the fragmentation of zeolites contained. Recrystallization of the sample with NaOH at a temperature of 170 °C yielded a zeolite with ANA topology. The addition of natural crystalline material from Indonesia as seeds in hydrothermal treatment of zeolite synthesis at 170 °C and 65 °C consecutively yielded zeolite with the topology of ANA and GIS. The difference resulted from temperature leads to the potential of inter-zeolite transformation. SEM images of seed- assisted ANA showed significant improvement of surface morphology and smaller crystal size. Further investigations were made by altering the initial Si/Al ratio, and it was found that a lower Si/Al ratio resulted in greater crystal size and yield percentage. The series of experiments proved that the Messawa natural mineral sample contains a secondary building unit type 4, the same building block between GIS and ANA. Substitution of the silica source with TEOS provides a faster nucleation rate. Hence, it has the potential to produce zeolites with other topology, SOD.