Synthesis of T-type zeolite nanoparticles for the separation of CO2/N2 and CO2/CH4 by adsorption process

• The synthesis of T-type zeolite using the hydrothermal method was studied.
• The T-type zeolites with particle size 150–200 nm were successfully synthesized.
• The CO2 separation performance of the synthesized T-type zeolite was evaluated.
• The T-type zeolites nanoparticles showed promising CO2 separation performance.

The effects of aging, crystallization temperature and time, and structure directing agent (SDA) on the synthesis of T-type zeolite nanoparticles were investigated systematically. The synthesized zeolites were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET measurements. Under optimal synthesis conditions, pure T-type zeolites with a particle size of 150–200 nm were successfully prepared in a time period as short as 120 h. The equilibrium adsorption of pure gases CO2, N2, and CH4 on the synthesized T-type zeolite nanoparticles were measured at 288, 298 and 313 K. The T-type zeolite nanoparticles showed the capability of selective adsorption of CO2 over N2 and CH4. At 288 K and 100 kPa, the selectivity of CO2/N2 and CO2/CH4 of the T-type zeolite nanoparticles was 53.71 and 19.15 respectively. Compared to the micro-level T-type zeolite particles, the T-type zeolite nanoparticles exhibited a higher CO2 adsorption capacity. At 288 K and 100 kPa, the T-type zeolite nanoparticles showed 4.01 mmol/g CO2 adsorption capacities, 30% higher than micro-level T-type zeolite. The dynamic adsorption experiments of CO2/N2 and CO2/CH4 binary gas mixtures demonstrated that the synthesized T-type zeolite nanoparticles have promising adsorption capability and recyclability for the separation of CO2/N2 and CO2/CH4 in the potential application to post-combustion CO2 separation or natural gas purification process.