Composites ZSM-5/KIT-6 Synthesized Via Assembly Modification Procedure and Mechanical Grinding Procedure, Respectively, and Their Application to CO2 Adsorption

The micro/mesoporous composite ZSM-5/KIT-6 was synthesized via the assembly procedure of preformed ZSM-5 seeds into mesostructured KIT-6, and mechanical mixtures with different contents of zeolite were prepared via a mechanical grinding procedure. These composites were used as adsorbents for the capture of CO2 in the simulated flue gas conditions of 60 degrees C and 15 vol% CO2 with a thermal gravimetric analyzer (TGA). The combination of dual-pore structures improved the adsorption performance. The composite synthesized via the assembly procedure exhibited superior adsorption capacity to the mechanical mixtures. The maximum adsorption capacity was 1.223 mmol/g. For mechanical mixtures, the adsorption capacity was dependent on the ZSM-5 content and increased with the increase of ZSM-5 content. The composite can be applied for CO2 adsorption at flue gas temperature and desorption at regeneration temperature of 110 degrees C. The adsorption capacity showed only 3% attrition during five consecutive cyclic adsorption/desorption tests. The composites displayed excellent CO2 adsorption/desorption performance.