Temperature and leaching effects of Zeolite-X derived from Kaolin

Abstract Zeolites are microporous materials that find a lot of applications in today’s world due to their different properties. In this research, the effect of different calcination temperatures (700oC and 900oC) and acid leaching (7% and 15% dilution) on zeolite-X crystals has been investigated using the hydrothermal method. The results from the different sample characterization show that the SiO2/Al2O3ratio is approximately 5.6 while the Infrared spectra indicate that Zeolite-X was produced with slight shifts in the wavenumbers. The diffraction patterns show that in addition to the formation of zeolite-X crystals, other phases were also obtained. The thermal analysis indicates that the zeolite is stable below 500oC. Thermogravimetric study shows that after about 200oC, only about 13% of the mass was lost. The differential thermal analyzer indicates that the samples followed the same trend until a temperature of 300oC where the samples calcined at 700oC had a positive heat loss while the samples calcined at 900oC had a negative heat loss. The BET analyses show that the zeolite from samples calcined at 700oC had lower adsorption-desorption isotherms compared to those at 900oC. The pore volume and sizes of the former were also lower than those of the latter. These results have shown that leached kaolin is effective in producing zeolite-X samples.