Nikolopoulos Apostolos N, Igglessi-Markopoulou Olga, Papayannakos Nikolaos
School of Chemical Engineering, National Technical University of Athens, Zografou Campus, Heroon Polytechniou Str. 9, Athens 15780, Greece.
Ultrason Sonochem. 2004 May;11(3-4):183-6. doi: 10.1016/j.ultsonch.2004.01.029.
The aim of this study is to explore the potential benefits from the combined use of ultrasound irradiation and catalytic wet peroxide oxidation for the degradation of 4-hydroxybenzoic acid (4-HBA). The target compound degradation was studied under direct and indirect sonication, while silent conditions were employed as reference. The catalyst, a mixed (Al-Fe) pillared clay named FAZA, was in the form of powder and of extrudates. In the case of extrudates it was observed that ultrasound improves the catalyst performance due to reduction of diffusion resistance, thereby increasing the conversion after 4 h by 12-15 times. Increasing the initial concentration of 4-HBA was found to lead to lower conversion. The combined ultrasonic/catalytic process appears very promising for environmental applications.
本研究的目的是探索超声辐照与催化湿式过氧化氢氧化联合使用对4-羟基苯甲酸（4-HBA）降解的潜在益处。在直接和间接超声处理下研究了目标化合物的降解情况，同时以无声条件作为参照。催化剂是一种名为FAZA的混合（铝-铁）柱撑黏土，有粉末和挤出物两种形式。在挤出物的情况下，观察到超声由于降低了扩散阻力而提高了催化剂性能，从而使4小时后的转化率提高了12至15倍。发现增加4-HBA的初始浓度会导致转化率降低。超声/催化联合工艺在环境应用方面似乎很有前景。
