用XRD测定成型无黏结剂5A分子筛(5A-1、5A-6)晶体结构；用微机差热天平测定正己烷在5A-1和5A-6上的TG-DTA特性曲线,研究其表观脱附活化能和脱附特性参数；在动态吸附/脱附实验装置上测定正己烷在5A-1和5A-6分子筛上的氦气吹扫脱附曲线,考察其吹扫脱附性能.结果表明：成型无黏结剂5A-1和5A-6均具有较强的5A分子筛XRD特征峰,无任何杂峰；5A-1相对于5A-6分子筛的结晶度为64%；正己烷在5A-1和5A-6分子筛上均存在两个(DTA)脱附峰,第一脱附峰对应的表观脱附活化能分别为33.44和39.35 kJ⋅mol−1,第二脱附峰对应的表观脱附活化能分别为52.21和67.48 kJ⋅mol−1；正己烷在5A-1和5A-6上的脱附温度不宜小于200℃；在200℃下,用氦气吹扫可使正己烷在5A-1和5A-6分子筛上的脱附完全,且正己烷在5A-1脱附性能优于5A-6.%The crystal structures of binder-free 5A zeolite pellets (5A-1, 5A-6) were determined by XRD, and the results show that the 5A-1 and 5A-6 zeolite pellets have strong XRD characteristic peaks of 5A zeolite and no other miscellaneous peak. The relative crystallinity of 5A-1 zeolite is 64% compared to that of the 5A-6 zeolite. The apparent desorption activation energy and desorption parameters of n-hexane adsorbed on binder-free 5A zeolite pellets were studied by thermo gravimetric differential analyzer (TG-DTA). The helium purging desorption curves of n-hexane adsorbed on 5A-1 and 5A-6 zeolite pellets were studied by a dynamic adsorption and desorption experimental equipment. The TG-DTA profiles of n-hexane adsorbed on 5A-1 and 5A-6 zeolite pellets show two desorption peaks:the activation energies of the first desorption peak on 5A-1 and 5A-6 zeolite pellets are 33.44 kJ⋅mol−1and 39.35 kJ⋅mol−1, respectively, while the activation energies of the second desorption peak are 52.21 kJ⋅mol−1 and 67.48 kJ⋅mol−1, respectively. The suitable desorption temperatures of n-hexane adsorbed on 5A-1 and 5A-6 zeolite pellets all exceed 200℃. The n-hexane adsorbed on 5A-1 and 5A-6 zeolite pellets can completely desorbed by being purged with helium at 200℃, and the 5A-1 zeolite pellet has better desorption performance than that of 5A-6.
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