Ag-ZSM-5分子筛上乙醇氧化过程中积碳行为的研究

Carbon Deposit on Ag-ZSM-5 Molecular Sieve in Ethanol Oxidation

关键词:  积炭  ZSM-5  硅铝比

Key words:  carbon deposit  ZSM 5  Si/Al molar ratio

摘要:

用不同银含量及不同硅铝比的Ag-ZSM-5分子筛催化乙醇氧化成乙醛,采用高温氧化烧炭法考察了银含量、硅铝比及反应温度对催化过程中积炭行为的影响。结果表明:高SiO₂/Al₂O₃时积炭较慢;Ag含量超过10%,对积炭速率影响不大;反应温度高时积炭速率减慢,但是选择性及转化率降低。研究发现Sn改性的Ag-ZSM-5分子筛具有较好的抗积炭能力。

Abstract:

Ag-ZSM-5 was used to catalize the oxidation of ethanol to acetaldehyde,and the effects of Ag content,Si:Al ratio and reaction temperature on carbon deposit behavior in the oxidation were examined by the high temperature oxidation.The results showed that carbon deposit was slow at high SiO:Al₂O₃ ratio,and there were no much affection on carbon deposit at over 10% of Ag content;and carbon deposit was slow at high temperature,but selectivity and conversion were slow.It was found that Ag-ZSM-5 with being improved Sn had a good resistance to carbon deposit.