Abstract:

To obtain the spherical adsorbent with good adsorptive performance and high strength, the influence of dry air flow rate and bed thickness on the crystallinity of FAU zeolite in the adsorbent, as well as the calcination temperature and dry air flow rate effect on the adsorbent strength were investigated systematically. The X-ray diffraction measurement (XRD), thermogravimetric analyzer (TG) and intelligent particle strength tester were employed to characterize the samples. It is found that the higher flow rate of dry air and smaller bed thickness are in favor of lowering air humidity in the adsorbent bed, and consequently reducing the hydrothermal damage of FAU zeolite and remaining its crystlinity. The higher the calcination temperature, the higher the strength of the spherical adsorbent. When the calcination temperature exceeds 500 ℃, the binder, halloysite, in the adsorbent, is transformed into amorphous material, resulting in higher strength of the adsobent. The adsorbent strength also increases with the increase of dry air flow rate.

Key words: calcination condition, binder, FAU zeolite, halloysite