焙烧对球形吸附剂性能的影响

INFLUENCE OF CALCINATION ON PERFORMANCE OF SPHERICAL ADSORBENT

为了使焙烧后的球形吸附剂具备良好的吸附性能和强度,系统研究了干燥空气流速和床层厚度对吸附剂活性组元FAU分子筛结晶度的影响,以及焙烧温度和干燥空气流速对球形吸附剂强度的影响。采用X射线衍射仪、热重分析仪和智能颗粒强度测定仪对样品进行了表征和测试。结果表明:干燥空气流速越大、床层厚度越小、吸附剂床层中的空气湿度越低,活性组元FAU分子筛越不易发生水热破坏,其结晶度越高;焙烧温度越高,球形吸附剂强度越高,焙烧温度超过500℃时黏结剂埃洛石转化为无定形材料,此时,球形吸附剂的强度较高;干燥空气流速增大,球形吸附剂强度也随之增加。

To obtain the spherical adsorbent with good adsorptive performance and ta^gh strengm, 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 investi- gated 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 crystiinity. Tb, e higher the calcination temperature, the higher the strength of the spherical adsorbent. When the calci- nation temperature exceeds 500 ℃, the binder, halloysite, in the adsorbent, is transformed into amor- phous material, resulting in higher strength of the adsobent. The adsorbent strength also increases with the increase of dry air flow rate.