一步水热合成Mn-ZSM-5纳米分子筛及其性能

Synthesis and Property of Nano-sized Mn-ZSM-5 Zeolite via One-step Hydrothermal Method

在强碱性条件下直接引入二价锰源,一步合成出高纯度的纳米级Mn-ZSM-5分子筛.通过X射线粉末衍射(XRD)、傅里叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)、29Si核磁共振波谱(29Si NMR)、电感耦合等离子光谱(ICP)和氮气吸附-脱附等测试方法对其进行结构表征和性能测试.结果显示,锰原子存在于沸石骨架中,产物为具有MFI结构的纳米级分子筛.使用苯乙烯氧化反应作为探针反应,以过氧化氢为氧化剂,结果显示苯乙烯转化率达到84.98%,转化数(TON)为208,环氧苯乙烷选择性为87.62%,产率为74.46%.

High pure Mn-ZSM-5 zeolite was synthesized through one-step hydrothermal method by direct introduction of divalent manganese source under strong alkaline condition.The samples were characterized by XRD,FTIR,29Si NMR,SEM,ICP and N2 adsorption-desorption techniques.The results indicated that manganese irons were incorporated into the zeolite skeleton.Using styrene oxidation as a probe reaction,H2O2 as the oxidant and Mn-ZSM-5 as the catalyst,the conversion of styrene reached 84.98%,turnover number was 208,styrene epoxide selectivity and yield was about 87.62% and 74.46%,respectively.The synthesized nano sized Mn-ZSM-5 is a promising catalyst for oxidation reactions.