Effect of seed precursor on organic structure-directing agent free synthesis of SSZ-13 membrane and its dehydration performance
Effect of seed precursor on organic structure-directing agent free synthesis of SSZ-13 membrane and its dehydration performance
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DOI：
10.1016/j.micromeso.2022.112069
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发表时间：
2022-06
影响因子：
5.2
通讯作者：
Songyi Wang;Taohong Liu;Yirong Cao;Bin Xia;Ruizhi Yi;Peng Gao;Yanshuo Li
中科院分区：
文献类型：
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作者：
Songyi Wang;Taohong Liu;Yirong Cao;Bin Xia;Ruizhi Yi;Peng Gao;Yanshuo Li
采用无有机结构导向剂（OSDA）合成法制备了致密、纯净、脱水性能优异的SSZ-13分子筛膜。载体上的种子前驱体影响膜的物相、形貌和致密度。在不使用种子的情况下，形成具有显著裂纹的GIS膜。与H-SSZ-13晶种相比，NH 4-SSZ-13晶种的SSZ-13结晶速率更快。NH 4-SSZ-13晶种制备的SSZ-13晶体结晶度明显高于H-SSZ-13晶种。此外，采用NH 4-SSZ-13晶种可以得到纯的SSZ-13分子筛，而采用H-SSZ-13晶种制备的产物中GIS杂质和SSZ-13共存，表明NH 4-SSZ-13晶种比H-SSZ-13晶种对SSZ-13晶体的形成具有更强的诱导作用。因此，可以用NH 4-SSZ-13种子合成纯净且致密的SSZ-13膜。表征结果表明，SSZ-13膜是通过溶解-重结晶法制备的。在此基础上，对无OSDA法合成SSZ-13分子筛膜的工艺参数进行了系统优化。结果表明，合成温度、合成时间和合成凝胶组分对膜的形貌、物相和致密性均有影响。在此条件下制得的SSZ-13分子筛膜具有良好的重复性和较高的渗透汽化脱水性能，渗透液平均含水率为99.9%，平均水通量为1.82 kg/m2·h，表明采用无OSDA法制备的纯SSZ-13分子筛膜在渗透汽化脱水过程中具有潜在的应用价值。
Pure and compact zeolite SSZ-13 membrane with excellent dehydration performance was obtained with organic structure-directing agent (OSDA) free synthesis method. The seed precursor on the support affected the phase, morphology and compactness of the obtained membranes. Without the usage of the seed, GIS membrane with notable cracks were formed. Compared to the seed of H-SSZ-13, the crystallization rate of SSZ-13 crystal was faster with the NH4-SSZ-13 seed. And the crystallinity of SSZ-13 crystal prepared with NH4-SSZ-13 seed was obviously higher than that prepared with H-SSZ-13. In addition, the pure zeolite SSZ-13 can be obtained with NH4-SSZ-13 seed, while GIS impurities and SSZ-13 co-existed in the product prepared with H-SSZ-13 seed, indicating that NH4-SSZ-13 seed showed higher inductive effect than H-SSZ-13 seed on the formation of SSZ-13 crystal. Thus, pure and compact SSZ-13 membrane can be synthesized with NH4-SSZ-13 seed. The characterization results showed that the SSZ-13 membrane was obtained via dissolution-recrystallization route. Furthermore, the synthesis parameters of zeolite SSZ-13 membrane by OSDA free method were optimized systematically. The results revealed that synthesis temperature, time and the synthesis gel component would affect the morphology, phase and compactness of the obtained membrane. The SSZ-13 membrane with the optimal conditions showed good reproducibility and a relatively high pervaporation dehydration performance, the average water in permeate was 99.9%, and the average water flux was 1.82 kg/m2·h, implying that pure zeolite SSZ-13 membrane, which was obtained by OSDA free method with optimum synthesis parameters, showed a potential application value towards pervaporation dehydration process.