Ozone-assisted detemplation of SSZ-13 zeolite at low temperature

The template used in synthesis of the zeolites needs to be removed in order to activate the zeolite micropores. High-temperature calcination is a common process, but it is associated with high energy consumption, and often induces thermal shocks to the zeolite. In this study, a new approach for SSZ-13 zeolite detemplation is investigated as a viable alternative for conventional calcination at high temperature (>500 °C). The SSZ-13 zeolite is exposed to ozone gas at 180, 190 and 200 °C which are much lower than the required temperature for the calcination. SEM, TGA, FTIR, BET experiments and CO2/CH4 adsorptive performance analyses, the Langmuir isotherm, and the IAS theory were utilized to evaluate the efficiency of this process compared to the calcination approach. SSZ-13 zeolite was successfully detemplated using ozonication process, showing porosity characteristics close to that of a thermally calcined sample. According to results, the best detemplation was achieved at 200 °C and O3 concentration of 41 g Nm−3. The BET surface area of zeolite was 441 m2 g−1 during the mentioned condition while that of calcined powder was 513 m2 g−1. Just a 14.03% drop in surface area is acceptable when a considerable amount of energy is saved compared to the calcination. For the mentioned ozonicated sample, a 28% reduction in CO2 adsorption was resulted while selectivity of 61.62 for CO2/CH4 binary system was estimated using the IAS theory which is an increase about 28.59% compared to calcined sample. [Display omitted] •The ozonication process is used to remove the template of the SSZ-13 zeolite.•Different operational conditions affecting the ozonication process are studied.•CO2 separation from CH4 gas using ozonicated zeolite was investigated.•The sample ozonicated in 200 °C showed the best CO2 separation with CO2/CH4 selectivity of 62.•IAST was applied in order to estimate separation performance of the ozonicated zeolite in mixed gases.