Methylcellulose-Directed Synthesis of Nanocrystalline Zeolite NaA with High CO2 Uptake

Materials

Dilshod Shakarova¹  Arto Ojuva¹  Lennart Bergström¹ 

[1]Department of Materials and Environmental Chemistry, Stockholm University, Stockholm 10691, Sweden

[2] E-Mails:

关键词: zeolite NaA;    nanocrystals;    hydrothermal synthesis;    carbon dioxide adsorption;   

DOI  :  10.3390/ma7085507

来源: mdpi

【 摘 要 】

Zeolite NaA nanocrystals with a narrow particle size distribution were prepared by template-free hydrothermal synthesis in thermo-reversible methylcellulose gels. The effects of the amount of methylcellulose, crystallization time and hydrothermal treatment temperature on the crystallinity and particle size distribution of the zeolite NaA nanocrystals were investigated. We found that the thermogelation of methylcellulose in the alkaline Na₂O-SiO₂-Al₂O₃-H₂O system played an important role in controlling the particle size. The synthesized zeolite nanocrystals are highly crystalline, as demonstrated by X-ray diffraction (XRD), and scanning electron microscopy (SEM) shows that the nanocrystals can also display a well-defined facetted morphology. Gas adsorption studies on the synthesized nanocrystalline zeolite NaA showed that nanocrystals with a size of 100 nm displayed a high CO₂ uptake capacity (4.9 mmol/g at 293 K at 100 kPa) and a relatively rapid uptake rate compared to commercially available, micron-sized particles. Low-cost nanosized zeolite adsorbents with a high and rapid uptake are important for large scale gas separation processes, e.g., carbon capture from flue gas.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.