Characterization of Metal Phthalocyanine Catalysts Using Field Desorption Mass Spectrometry

Metal phthalocyanines are a very important class of compounds due to their ability to activate oxygen, which enables them to be come useful chemical reagents and largely-accepted catalysts for many chemical reactions. Phthalocyanines containing metals like iron, cobalt, manganese and vanadium are useful catalysts in many refinery processes. In the petroleum industry mercaptans are oxidized to disulfides by aerobic oxidation in an alkaline medium in the presence of a metal phthalocyanine. A number of analytical techniques have been explored to characterize metal phthalocyanines. In this article, we have for the first time successfully used field desorption mass spectrometry (FDMS) techniques for the characterization simple metal phthalocyanines and substituted metal phthalocyanines. For this purpose metal phthalocyanines were prepared in the laboratory and the conditions were optimized for the characterization of metal phthalocyanines containing cobalt, nickel, copper and zinc by FDMS. This technique was also successfully applied to characterize sulfato, nitro, and chloro substituted phthalocyanines. This technique has been found to be a useful tool for the characterization of phthalocyanines.