Transformation of Mordenite-Clinoptilolite Natural Zeolite at Different Calcination Temperatures

Natural zeolite is one of prospective material with various applications. The material has low-cost provisioning and abundant availability in the world. Mordenite-clinoptilolite is one of the common types of natural zeolite; one of the deposits are located in Gunungkidul, Yogyakarta, Indonesia. For optimizing the utilization, some treatment is needed, calcination being one of the possible treatments. The dealuminated natural zeolite was used as the base material for understanding the transformation effect, then calcinated the zeolite in various temperature range between 400 degrees C and 1000 degrees C. Some characterization was conducted after the treatment, such as XRD, SEM-EDX, and BET to explore the structure, morphology, composition, and specific surface area. Drastic structure changes were demonstrated at the calcination of 1000 degrees C which eliminating the zeolite structure into cristobalite as one of the silica structures. The specific surface area decreased after 600 degrees C, even elapsed after the structure change. Calcination has the ability to transform the zeolite structures and also affected the specific surface area properties. This transformation provides critical information for further application of natural zeolite in the various treatment of calcination.