Abstract: A method of degrading an organic nitrogen compound to its reduction products, in which the compound is caused to react with a reducing agent in the presence of a complex of a corrin containing a metal-centered ring system. Preferred complexes are cobalt-centered hydrolysis products of Vitamin B12, such as cobyrinic acid, and in one embodiment these complexes are immobilised on a substrate. Using the method environmental pollutants such as nitrobenzenes may be rapidly reduced.

Abstract: A method for dehalogenation of organohalogen compounds, e.g. environmental pollutants in industrial waste. The organohalogen is reacted with a reducing agent in the presence of a selected metal-centered corrin, porphyrin or phthalocyanine complex. Preferred complexes are hydrolysis products of cyanocobalamin, of formula (I), in which R.sup.1 is NH.sub.2 or OH, R.sup.2 is H, CH.sub.2 CH.sub.2 COOH or CH.sub.2 CH.sub.2 CONH.sub.2, R.sup.3 is H, CH.sub.2 CH.sub.2 COOH or CH.sub.2 CH.sub.2 CONH.sub.2, and R.sup.4 is NHCH.sub.2 CH(OH)CH.sub.3, OH or NH.sub.2. The complex is preferably immobilized on a substrate. Some novel metal-centered porphyrin complexes are also described. A dehalogenation apparatus using the method of the invention is also described.