observation was found when the volume of the solvent increased to 30 mL. Besides, catalytic condensation can be performed at free solvent conditions and at room temperature; however, when decrease temperature, a higher number of isomers was observed rather than the desired product. In addition, catalytic condensation was also evaluated in biomass of essential oils and mixtures with sesquiterpenes showing
在此贡献中,使用湿法浸渍制备了基于杂多酸(HPA,H 3 PW 12 0 40
水合物)负载在几种金属氧化物(TiO 2,SiO 2,SBA-15,Al 2 O 3 )上的异质材料,通过XRD表征,FTIR,
SEM,
TPD酸度,氮物理吸附,拉曼光谱,31 P NMR,然后在
柠檬烯与
苯甲醛的催化缩合反应中进行评估。在每个载体上加入 HPA 后,没有观察到结构变化,如 FTIR、RAMAN 和 XRD 所示。
TPD-NH 3酸度分析表明增加 HPA 的量会增加催化剂的酸度,直到它保持恒定(20-30%)。氧化铝、
二氧化硅和 SBA-15 上的 HPA 也显示出高酸度值,但低于典型的 HPA/P25 催化剂(HPA 超过商业 Degussa P25)。最后一种是选择性最高的材料之一(表面积为 39 m 2 /g,酸度为 187 µmol NH 3 .g cat -1) 用于合成对
柠檬烯异构体副产物具有低选择性的