异丙醇-丙酮-氢气化学热泵中丙酮加氢反应选择性研究

Selectivity of Acetone Hydrogenation for Lsopropanol-Acetone-Hydrogen Chemical Heat Pump

采用实验与理论相结合的方法,对高温丙酮加氢反应副产物的产生路径和机理进行了系统深入研究。反应动力学实验发现高温丙酮加氢反应的主要产物为裂解产物,主要是一氧化碳和甲烷。空速、反应温度和压力的增加使丙酮转化率降低,同时异丙醇反应选择性降低,裂解产物选择性增加;提高氢气流量可以使丙酮转化率增大,同时异丙醇反应选择性增加,裂解产物选择性降低;获得了可以预测反应选择性的反应动力学方程。通过密度泛函理论计算了副产物的产生路径,发现丙酮的烯醇化是丙酮分解产物产生的源头,并指出采用Pt Cu催化剂并降低催化剂酸性可以改善丙酮加氢选择性。

The reaction pathway and mechanism of high-temperature acetone hydrogenation was studied by using combined experimental and computational method. The experimental results showed that the main side reaction is the cracking of the acetone and the main by-products are CO and methane. The increase of the space velocity, temperature and pressure decreases the conversion and selectivity of acetone, and the increment of the hydrogen flow rate increases the conversion and selectivity of acetone. The kinetic equations that can predict the selectivity of acetone was obtained. In addition, the DFT calculations suggested that the keto-enol isomerization is origin of the decomposition of acetone. And then the selectivity can be improved by using Pt Cu alloy catalyst and decreasing the acidic functions of the catalyst.