CAJ | 학술논문

采用探针-TPD、探针-IR和电势测量等方法研究不同浓度脲溶液浸泡γ-Al2O3 颗粒对γ-Al2O3 表面酸碱性质的影响和脲修饰对γ-Al2O3 及La2O3/γ-Al2O3 催化肉桂醛MPV反应的影响.结果表明,经不同浓度的脲溶液浸泡后,γ-Al2O3 表面酸、碱位点强度分布均发生变化,催化肉桂醛MPV反应,生成肉桂醇的选择性随着修饰用脲溶液浓度增加而下降.以脲溶液修饰的γ-Al2O3为载体制备的La2O3/γ-Al2O3 催化肉桂醛MPV反应,具有与γ-Al2O3 催化该反应类似的变化现象.
채용탐침-TPD、탐침-IR화전세측량등방법연구불동농도뇨용액침포γ-Al2O3 과립대γ-Al2O3 표면산감성질적영향화뇨수식대γ-Al2O3 급La2O3/γ-Al2O3 최화육계철MPV반응적영향.결과표명,경불동농도적뇨용액침포후,γ-Al2O3 표면산、감위점강도분포균발생변화,최화육계철MPV반응,생성육계순적선택성수착수식용뇨용액농도증가이하강.이뇨용액수식적γ-Al2O3위재체제비적La2O3/γ-Al2O3 최화육계철MPV반응,구유여γ-Al2O3 최화해반응유사적변화현상.
The influnence of the concentrations of urea aqueous solution on surface acidic and basic prop-erties of γ-Al2O3 was studied by probes-TPD,probes-IR and potential measure. The effects of modification of urea on catalytic performance ofγ-Al2O3 and La2O3/γ-Al2O3 catalysts for MPV reaction of cinnamalde-hyde were investigated. The experimental results showed that the intensity distribution of acid and base sites on γ-Al2O3 surface changed after γ-Al2O3 was soaked in the aqueous solution of urea with various concentrations. Using modifiedγ-Al2O3 as the catalyst for MPV reaction of cinnamaldehyde,the selectivity to cinnamyl alcohol decreased with the increase of urea solution concentration. Using La2O3/γ-Al2O3 catalyst prepared with modified γ-Al2O3 support by urea,the similar change of the selectivity to cinnamyl alcohol was also found.