摘要
以碳酸二乙酯(DEC)为乙基化试剂,与苯酚在气固相条件下催化合成苯乙醚。以活性炭(AC)为载体考察了不同活性组分及其负载量对催化剂活性的影响。实验结果表明,以K2CO3为活性组分,负载量达到20%(质量分数)时K2CO3/AC催化剂的活性较好。CO2程序升温脱附表征结果表明,K2CO3/AC催化剂的碱量随K2CO3负载量的增加先增大后减小,这主要是由于K2CO3负载量过多会堵塞催化剂的内孔,从而抑制其碱性中心发挥作用。同时还考察了反应温度、气态空速和原料配比对催化剂活性的影响,在反应温度593K、反应压力0.6MPa、反应时间7h、气态空速1500h-1、n(DEC)∶n(苯酚)=1.5的条件下,苯酚的转化率和苯乙醚的选择性都可达到100.00%。
Catalytic synthesis of phenetole by ethylation of phenol with diethyl carbonate( DEC ) in fixed bed reactor was investigated. Catalyst of 20% ( mass fraction) K2CO3 loaded on active carbon (AC) exhibited the high catalytic activity and stability. The CO2 -TPD and BET characterization show that basicity of K2CO3/AC increases with K2CO3 loading and reaches a maximum at 20% K2CO3. Further more K2CO3 loading may cause obvious lowering of BET specific surface area and pore volume. It may be the main reason for decreases of basicity and activity of the catalyst. The effects of reaction temperature, gas hourly space velocity (GHSV) and n ( DEC ) : n (phenol) on conversion of phenol and selectivity to phenetole were studied. Conversion of phenol increased with the reaction temperature, but DEC would decompose at higher temperature. Under reaction conditions of 593 K, 0.6 MPa,7 h, GHSV 1 500 h^-1 and n(DEC) : n(phenol) 1.5, both conversion of phenol and selectivity to phenetole can reach 100.00%.
出处
《石油化工》
EI
CAS
CSCD
北大核心
2007年第11期1157-1161,共5页
Petrochemical Technology
基金
国家重大基础研究前期研究项目(2003CCA03200)
江苏省高技术研究项目(BG2006015)
江苏省高校重大基础研究项目(06KJA5013)
关键词
碳酸二乙酯
苯酚
苯乙醚
碳酸钾
活性炭
乙基化
固体碱催化剂
diethyl carbonate
phenol
phenetole
potassium carbonate
active carbon
ethylation
solid base catalyst