THE EFFECT OF TRANSITION METAL COATINGS ON THE ABILITY OF CALCIUM OXIDE TO DESTRUCTIVELY ADSORB CARBON TETRACHLORIDE

S. Decker¹ and K.J. Klabunde²

Department of Chemistry, Kansas State University, Manhattan, KS, 66506, ¹913-532-6829 and ²913-532-6849


ABSTRACT

Chlorinated organic compounds are a hazard to the environment and to humans. Although many of these compounds are generated by nature, there has been concern about the effect of manmade chlorinated compounds on the environment. This recent concern has spurred research investigating environmentally benign disposal methods for these chemicals.

Previous research has shown that nanometer sized calcium oxide particles are effective in destroying some simple compounds of hazardous concern. It has also been shown that magnesium oxide will also destroy some of these chemicals and that iron coated magnesium oxide shows an enhanced reactivity relative to uncoated magnesium oxide. Typically the transition metal loading is 1-5% of the molar amount of the magnesium oxide substrate.

The purpose of the current research is to see if the same enhanced reactivity occurs with CaO particles which are less expensive to manufacture. This research investigates the effect of nickel, copper and zinc coatings on the ability of calcium oxide particles to destructively adsorb carbon tetrachloride. Carbon tetrachloride was chosen as a model compound because its reaction with CaO is simple and easy to monitor. The products of the reaction are simply calcium chloride and carbon dioxide.

Preliminary results show that nickel coated calcium oxide has an enhanced reactivity relative to uncoated calcium oxide. It has also been observed that the particles may exhibit a "catalytic" reactivity rather than stoichiometric and, therefore, may be extremely useful in the degradation of harmful chlorinated organic compounds.

KEY WORDS

destructive adsorption, chlorinated organics

This paper is from the Proceedings of the 10th Annual Conference on Hazardous Waste Research 1995, published in hard copy and on the Web by the Great Plains/Rocky Mountain Hazardous Substance Research Center.