CAJ | 학술논문

采用原位红外技术研究了碳酸二甲酯在氧化镁、氟化镁、镁铝复合氧化物和氟改性的镁铝复合氧化物 4种固体碱表面上的吸附和活化行为.结果表明: 碳酸二甲酯以单、双齿两种形态吸附于固体碱的表面,双齿吸附的比单齿吸附的更易活化.碳酸二甲酯吸附于氧化镁和镁铝复合氧化物上活化生成甲氧基, 吸附于氟化镁上活化生成甲氟基;而吸附于氟改性的镁铝复合氧化物上优先活化生成甲氟基, 随着吸附表面温度的升高,逐渐有甲氧基生成,说明氟改性的镁铝复合氧化物是一种优良的甲基化反应催化剂.
채용원위홍외기술연구료탄산이갑지재양화미、불화미、미려복합양화물화불개성적미려복합양화물 4충고체감표면상적흡부화활화행위.결과표명: 탄산이갑지이단、쌍치량충형태흡부우고체감적표면,쌍치흡부적비단치흡부적경역활화.탄산이갑지흡부우양화미화미려복합양화물상활화생성갑양기, 흡부우불화미상활화생성갑불기;이흡부우불개성적미려복합양화물상우선활화생성갑불기, 수착흡부표면온도적승고,축점유갑양기생성,설명불개성적미려복합양화물시일충우량적갑기화반응최화제.
The adsorption and activation of dimethyl carbonate on the surface of solid base were investigated by in situ FTIR, and the solid bases included magnesia, magnesium fluoride, Mg-Al mixed oxide and fluorine-modified Mg-Al mixed oxide. The FTIR results showed that dimethyl carbonate adsorbed on the surface of solid based by two modes of bidentate and unidentate complex. The bidentate was more active than the unidentate. Methoxyl group was formed from the adsorbed dimethyl carbonate on the surface of magnesia and Mg-Al mixed oxide. And fluomethyl group was formed from the adsorbed dimethyl carbonate on the surface of sodium fluoride. However, dimethyl carbonate on the surface of fluorine-modified Mg-Al mixed oxide showed preference for generating fluomethyl group. With the increasing of the treating temperature of samples, the methoxyl group was gradually formed on the surface. Accordingly, the fluorine-modified Mg-Al mixed oxide was found to be an excellent catalyst for methylation.