MIL-100(Fe)催化正戊醛自缩合反应性能

MIL-100 (Fe) Catalyzed Self-Condensation of n-Valeraldehyde

摘要:

摘要：以硝酸铁和苯三甲酸为原料，采用水热法制备了金属有机骨架材料MIL-100(Fe)催化剂，采用XRD、SEM、BET对其结构进行了表征。评价了MIL-100(Fe)催化正戊醛自缩合合成2-丙基-2-庚烯醛的反应性能。根据GC-MS分析结果，推测了该反应体系中的副产物以及可能发生的副反应。通过条件优化实验，得到适宜的反应条件为：催化剂质量分数为15%（以正戊醛的质量为基准，下同）、反应温度为130 ℃、反应时间为8 h。在此条件下，正戊醛转化率为73.5%，2-丙基-2-庚烯醛收率和选择性分别为63.2%和86.0%。MIL-100(Fe)催化剂重复使用4次后，催化活性没有明显下降，通过XRD、FTIR分析证明其催化剂结构未发生坍塌。建立了MIL-100( Fe)催化正戊醛自缩合反应网络。

Abstract:

Abstract: Metal-organic frameworks MIL-100(Fe) catalyst was prepared by hydrothermal method using ferric nitrate and benzene tricarboxylic acid as raw materials. Its structure was characterized by XRD, SEM and BET. The catalytic performance of MIL-100(Fe) for n-valeraldehyde self-condensation to 2-propyl-2-heptenal was evaluated. The components existing in the reaction system were identified by GC-MS analysis. The effect of reaction conditions on 2-propyl-2-heptenal synthesis was investigated and the suitable reaction conditions were determined as follows: a weight percentage of MIL-100(Fe)=15% (benchmarked against the quality of n-valeraldehyde, the following is the same), reaction temperature of 130 ℃, and reaction time of 8 h. Under the above conditions, the conversion of n-valeraldehyde was 73.5%, and the yield and selectivity of 2-propyl-2-heptenal were 63.2% and 86.0%, respectively. The MIL-100(Fe) catalyst could be reused for four times without a significant loss in its catalytic activity. XRD, FTIR analysis showed that the catalyst structure did not collapse. Lastly a possible reaction network of n-valeraldehyde self-condensation catalyzed by MIL-100(Fe) was established based on speculation of the side-reactions.