摘要
采用共沉淀法和浸渍法在不同条件下制备了稀土-SO42-/ZrO2系列固体酸催化剂。使用废油脂与甲醇的酯交换反应评价了催化剂活性,并通过X射线衍射、红外光谱、比表面积测定表征方法考察了催化剂结构和性能的关系。结果表明,La摩尔掺杂量4%、焙烧温度600℃时制得的SO42-/ZrO2-La2O3催化剂活性最高,此时脂肪酸甲酯的产率为64.68%,且具有较好的重复使用性。稀土的引入使活性四方相ZrO2更加稳定,600℃焙烧使催化剂既具有较多活性四方相ZrO2,又具有较大比表面积,从而提高了催化剂活性。催化剂中形成了固体超强酸结构,且改性后酸强度增大,催化剂活性中心数目增加。
The rare earth-promoted SO42-/ZrO2 solid super acid catalyst was prepared by the co-precipitation and impregnation method under different conditions.The catalytic properties of the samples were evaluated through transesterification of waste oil and methanol and characterized by X-ray diffraction（XRD）,Fourier transform infrared spectroscopy（FT-IR） and BET surface area measurement.The results showed that among all the prepared samples the one that was calcined at 600 ℃ with La doping 4% had the highest production rate of 64.68%.An analysis of XRD patterns revealed that the incorporation of rare earth into tetragonal zirconia stabilizes the compound,and the calcination at 600 ℃ increases the reactivity of the catalyst by producing a greater fraction of active tetragonal zirconia with a larger surface area.It could be seen from the FT-IR spectra that super acid structures were formed in the catalysts and the acidity was strengthened remarkably and the activated centre of the catalyst were increased.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2012年第4期412-417,共6页
Journal of Fuel Chemistry and Technology
基金
黑龙江省科技攻关资助项目(G209A302)
关键词
固体酸
稀土
生物柴油
酯交换
焙烧温度
solid super acid
rare earth elements
biodiesel
transesterification
calcination temperature
