二氧化硫的电化学氧化过程：Ⅰ.电极材料的影响

采用循环伏安法研究了SO_2在多种电极(催化剂)上的电化学氧化过程。根据催化剂上是否存在表面氧化物以及SO_2吸附形态的不同,可将所研究的催化剂分为三种类型。第一类以Au、Pt、Pd为代表,第二类以Ru、Rh、Ir为代表,第三类以聚钴卟啉类N_4大环配合物为代表。并对SO_2在三类催化剂上反应的特点进行了讨论。

ANODIC OXIDATION OF SULFUR DIOXIDE Ⅰ.INFLUENCE OF ELECTRODE MATERIAL

The anodic oxidation reaction of sulfur dioxide in 0.5mol/L H_2SO_4 with different elec-trode material (as catalyst) have been compared through cyclovoltametry. All the catalystsstudied can be divided into three groups. For the first group, such as Pt, Au, Pd, thereare two anodic current peaks on the cyclovoltamograph. The sulfur dioxide is oxidized firstby direct discharging at the potential below 1.0V and further by the surface oxide of thecataly st atmore positive potential. For the second group of the catalysts, such as Ir, Ru,and Rh,there is only one anodic current peak and the sulfur dioxide is oxidized by thesurface oxide of the catalyst.For the third group,as porphyrin, there also exists one anodiccurrent peak on the cyclovoltamograph,but the sulfur dioxide is oxidized by direct dischargeof the SO_2 molecules.