Abstract:

The high-speed scouring and strong centrifugal force of the liquid in the rotating packed bed reactor (RPB) can easily cause the coating and active components of the monolithic catalyst to fall off the surface of the matrix and cause losses, which limits the application of monolithic catalysts in RPB reactors. Therefore, it is important to investigate the adhesion of coatings and active components to improve the catalytic activity and lifetime of monolithic catalysts in the RPB reactor. In this work, the SiO₂ coating was deposited on nickel foam by the high gravity spraying method to prepare Pd/SiO_2(x)/NF monolithic catalysts. The monolithic catalysts were characterized by ultrasonic oscillation test, BET, XRD, SEM and XPS. When the rotational speed was 1200 r/min, the monolithic catalyst had the excellent adhesion performance, and the mass loss rate of the coating was 4%. The Pd/SiO_2(1200)/NF monolithic catalyst exhibited good catalytic activity in the hydrogenation of p-nitroanisole (PNA) to p-aminoanisole (PA) reaction in the RPB reactor, and the conversion of PNA was 98.9% within 180 min. This work provides a new strategy for the development of stable monolithic catalysts.

Key words: rotating packed bed reactor, monolithic catalyst, adhesion, catalytic hydrogenation

摘要：

旋转填充床反应器（RPB）中液体的高速冲刷和较强的离心力容易导致整体式催化剂的涂层和活性组分从基体表面脱落造成损失，限制了整体式催化剂在RPB反应器中的应用。因此，研究整体式催化剂涂层和活性组分的黏附性，以提升催化剂在RPB反应器中的催化活性和使用寿命具有重要意义。基于此，采用超重力喷涂法在泡沫镍（NF）基体表面负载氧化硅（SiO₂）涂层，制备了具有高黏附性的Pd/SiO_2(x)/NF整体式催化剂，通过超声振荡、BET、XRD、SEM和XPS等对整体式催化剂进行测试和分析。当RPB反应器的转速为1200 r/min时，整体式催化剂具有优异的黏附性能，涂层的脱落率为4%。以对硝基苯甲醚（PNA）催化加氢制备对氨基苯甲醚（PA）为探针反应，RPB反应器中Pd/SiO_2(1200)/NF整体式催化剂具有较好的催化活性，180 min 时PNA转化率为98.9%。本工作可为开发高黏附性的整体式催化剂提供新的途径。

关键词: 旋转填充床反应器, 整体式催化剂, 黏附性, 催化加氢