Preparation Of Zeolite SSZ-13for N₂/CO₂Separation

Increasing concentration of CO2in the atmosphere may bring bad influence onenvironment, mainly including global warming, global climate change, the influenceof the structure and material cycle in the ecosystem, impact on crops, forest andgrassland, and the resulting social and economic effect. Most of the CO2is producedby hunman activities, especially by the burning of fossil fuels. Bacause about80%ofglobal energy supply will still rely on fossil fuels in the future, the studies on CO2capture from the fuel gas became very important.Because the concentration of CO2in the fuel gas is very low, so using themethod of separation at low temperature, absorption method, membrane method tocapture CO2more or less have some shortcomings. The adsorption method withlow-energy cost, simple equipment, wide range of pressure and temperature becamethe most useful method for capturing CO2.Firstly, Zeolite SSZ-13was synthesized by a traditional hydrothermal method asabsorbent, and characterized with powder X-ray diffraction (XRD), scanning electronmicroscopy (SEM), and transmission electron microscopy (TEM). The porousstructure of the samples was determined from N2uptake measurements at77K, andthe surface properties were analyzed by Fourier transform infrared (FTIR)spectroscopy. The zeolite SSZ-13had a type I isotherm with a uniform pore sizedistribution and most pores were <1nm. The Langmuir surface area was703m2/g.The adsorption of various gases on the zeolite SSZ-13was studied experimentally anda high selectivity for CO2over N2was acheived.Next, studied Zeolite SSZ-13for CO2/N2separation performance. Resultsshowed that the molecular sieve SSZ-13for CO2/N2has good separation coefficient,and according to the breakthrough curves, changing the pressure had little influenceon the CO2/N2separation coefficient, can be ignored.Finally, investigates regeneration performance of Zeolite SSZ–13. Resultsshowed that the regeneration ratio increased as the regeneration temperature increased.Zeolite SSZ-13can be almost completely regenerated by placing it in a vacuum andthe material maintains good stability after being regenerated five times.