A new type of composite adsorbents was synthesized by incorporating monoethanol amine （MEA） into β-zeolite. The parent and MEA- functionalized β-zeolites were characterized by X-ray diffraction （XRD）, N2 adsorpt...A new type of composite adsorbents was synthesized by incorporating monoethanol amine （MEA） into β-zeolite. The parent and MEA- functionalized β-zeolites were characterized by X-ray diffraction （XRD）, N2 adsorption, and thermogravimetric analysis （TGA）. The adsorption behavior of carbon dioxide （CO2）, methane （CH4）, and nitrogen （N2） on these adsorbents was investigated at 303 K. The results show that the structure of zeolite was well preserved after MEA modification. In comparison with CH4 and N2, CO2 was preferentially adsorbed on the adsorbents investigated. The introduction of MEA significantly improved the selectivity of both CO2/CH4 and CO2/N2, the optimal selectivity of CO2/CH4 can reach 7.70 on 40 wt% of MEA-functionalized β-zeolite （MEA（40）-β） at 1 atm. It is worth noticing that a very high selectivity of CO2/N2 of 25.67 was obtained on MEA（40）-β. Steric effect and chemical adsorbate-adsorbent interaction were responsible for such high adsorption selectivity of CO2. The present MEA-functionalized β-zeolite adsorbents may be a good candidate for applications in flue gas separation, as well as natural gas and landfill gas purifications.展开更多
Zeolite β was aluminated with aqueous solution of NaAlO2. The product wascharacterized by means of XRD, FTIR techniques. After alumination, the Si/Al ratio ofzeolite β is greatly decreased (from 15.2 to 3-4), and th...Zeolite β was aluminated with aqueous solution of NaAlO2. The product wascharacterized by means of XRD, FTIR techniques. After alumination, the Si/Al ratio ofzeolite β is greatly decreased (from 15.2 to 3-4), and the crystallinity is retained mostly.Alumination is favoured by increasing the amount of added NaAlO2 and temperature, aproper high pH condition is also favourable. However, too high alkalinity leads to thedestruction of the framework.展开更多
基金supported by the Major Basic Research Project of Natural Science Foundation of Jiangsu Province Colleges (No. 08 kJA530001)the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT0732)
文摘A new type of composite adsorbents was synthesized by incorporating monoethanol amine （MEA） into β-zeolite. The parent and MEA- functionalized β-zeolites were characterized by X-ray diffraction （XRD）, N2 adsorption, and thermogravimetric analysis （TGA）. The adsorption behavior of carbon dioxide （CO2）, methane （CH4）, and nitrogen （N2） on these adsorbents was investigated at 303 K. The results show that the structure of zeolite was well preserved after MEA modification. In comparison with CH4 and N2, CO2 was preferentially adsorbed on the adsorbents investigated. The introduction of MEA significantly improved the selectivity of both CO2/CH4 and CO2/N2, the optimal selectivity of CO2/CH4 can reach 7.70 on 40 wt% of MEA-functionalized β-zeolite （MEA（40）-β） at 1 atm. It is worth noticing that a very high selectivity of CO2/N2 of 25.67 was obtained on MEA（40）-β. Steric effect and chemical adsorbate-adsorbent interaction were responsible for such high adsorption selectivity of CO2. The present MEA-functionalized β-zeolite adsorbents may be a good candidate for applications in flue gas separation, as well as natural gas and landfill gas purifications.
文摘Zeolite β was aluminated with aqueous solution of NaAlO2. The product wascharacterized by means of XRD, FTIR techniques. After alumination, the Si/Al ratio ofzeolite β is greatly decreased (from 15.2 to 3-4), and the crystallinity is retained mostly.Alumination is favoured by increasing the amount of added NaAlO2 and temperature, aproper high pH condition is also favourable. However, too high alkalinity leads to thedestruction of the framework.
