Cloth catalysts for water denitrification II. Removal of nitrates using Pd-Cu supported on glass fibers

The use of glass fibers in the form of woven cloth (GFC), as a new type of catalytic support, was studied far the reduction of aqueous nitrate solutions using a Pd/Cu-GFC catalyst. The activity (per gram Pd) and selectivity to nitrogen were found to be comparable with those found for Pd-Cu catalysts supported on the other carriers. The maximal initial removal activity was found for a catalyst with a Pd/(Pd + Cu) ratio of 0.81. The corresponding activity was 0.7 mmol min(-1) (g(Pd))(-1), and the selectivity was 97 mol% at 25 degreesC and pH 6.5 for initial nitrate concentration of 100 mg l(-1). The selectivity to nitrogen declined at high conversions of nitrate and high pH. (C) 2001 Elsevier Science B.V. All rights reserved.