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论文类型：期刊论文

发表时间：2017-11-01

发表刊物：MICROPOROUS AND MESOPOROUS MATERIALS

收录刊物：SCIE、EI

卷号：252

页面范围：146-153

ISSN号：1387-1811

关键字：Seed-assisted synthesis; ZSM-23; Alkali metal ions; Acidity; Hydroisomerization

摘要：The seed-assisted synthesis of ZSM-23 zeolite in the absence of alkali metal ions (denoted as SNNa) was investigated. Highly crystallized SNNa with needle-shape morphology and size of 500-1100 nm in length and 50-200 nm in diameter can be synthesized. Much attention was paid to the roles of alkali metal ions during the crystallization process. The absence of Na+ can effectively avoid the impurity quartz formation and promote SNNa crystallization in a broad range of SiO2/Al2O3 ratio between 80 and 200, whereas the crystallization rate was slowed down at the same time. On the contrary, the presence of Na+ had a significant effect both on the nucleation and crystal growth processes. The bifunctional catalyst Pt/H-SNNa prepared, showed good catalytic performance in the hydroisomerization of n-hexadecane due to its small crystal size, appropriate acidity and acid site distribution. (C) 2017 Elsevier Inc. All rights reserved.