Chemical Demulsification and Immobilization of Pd Nanoparticles in W/O Microemulsion by Conductivity Method
ZHOU Yong-hua YE Hong-qi ZHONG Hong
College of Chemistry and Chemical Engineering, Central South University College of Chemistry and Chemical Engineering, Central South University College of Chemistry and Chemical Engineering, Central South University, Changsha Hunan
Abstract:The well dispersed palladium nanoparticles with 5~10 nm in diameter were prepared in water-Tween-80-Span-80- cyclohexane microemulsion. The mixture composed of demulsifying agent and microemulsion presents subsequently microemulsion, delamination and colloid or microemulsion with the increase of amount of demulsifying agent. The hydrophilic property and molecular structure of demulsifying agent are considered as the main property factors affecting the demulsifying behavior. Adopting the critical region of delamination and homogenous system, the immobilization of palladium nanoparticles on the surface of support can be realized by simultaneous impregnation of a-Al2O3 support and chemical demulsifying. Analytical results of TEM and XPS show that Pd nanoparticles on the surface of support have the sizes of 10~20 nm in diameter and exist in Pd metallic state.