摘要
应用超声技术在温和条件下制得了4种嫁接离子液体的S iO2催化剂([N(CH2CH3)4]C l-A lC l3/S iO2,[N(CH2CH3)4]C l-SnC l4/S iO2,[N(CH2CH3)4]C l-ZnC l2/S iO2,[N(CH2CH3)4]C l-FeC l3/S iO2),用吡啶吸附的傅里叶变换红外光谱和N2吸附-脱附对催化剂的酸位、酸强度和结构进行了表征,并用甲醇和环氧丙烷合成丙二醇醚的反应评价了催化剂的性能。实验结果表明,4种催化剂中S iO2载体的孔结构基本没有改变,酸强度的强弱顺序为:[N(CH2CH3)4]C l-A lC l3/SiO2>[N(CH2CH3)4]C l-SnC l4/SiO2>[N(CH2CH3)4]C l-ZnC l2/S iO2>[N(CH2CH3)4]C l-FeC l3/S iO2。在甲醇和环氧丙烷合成丙二醇醚反应中,在4种催化剂上的环氧丙烷转化率均大于94%,催化活性高。催化剂重复使用6次后的实验结果表明,嫁接离子液体的S iO2催化剂的重复使用性和稳定性较好。
SiO2 was grafted with four kinds of ionic liquids by means of ultrasonic technique under mild conditions and then used as catalysts for probe reaction of propylene glycol methyl ether synthesis from methanol and propylene oxide. The catalysts were [ N （ CH2CH3 ）4]Cl-AlCl3/SiO2, [N（ CH2CH3 ）4] Cl-SnCl4/SiO2, [ N（ CUECH3 ）41 Cl-ZnCl2/SiO2 and[N（ CH2CH3 ）4] Cl-FeCl3/SiO2. Four kinds of catalyst were characterized by means of Py-b-TIR and N2 adsorption-desorption to determine their structures and acid strengths. During grafting process, structures of SiO2 in catalysts remained without damage but the Lewis acid strengths changed. The acid strengths follow the order of [ N（CHECH3）4] Cl-AlCl3/SiO2 〉[N（ CH2CH3）4] Cl-SnC14/SiO2 〉 [ N（ CH2CH3）4] Cl-ZnCl2/SiO2 〉 [N（CH2CH3）4] Cl-FeCl3/SiO2. Four kinds of catalysts all show good catalytic activity for the synthesis. Conversions of propylene oxide are all more than 94%. The ionic liquids grafted catalysts can be reused for 6 times. Their stabilities are still satisfactory.
出处
《石油化工》
EI
CAS
CSCD
北大核心
2006年第8期711-715,共5页
Petrochemical Technology
关键词
氧化硅
离子液体
甲醇
环氧丙烷
超声技术
催化剂
silica
ionic liquids
methanol
propylene oxide
ultrasonic technique
catalyst
