US EPA

4843825 

Journal Article 

A New Application of Landolt-Type Reactions. The Determination of Molybdenum Copper and Vanadium 

Weisz, H; Pantel, S 

1975 

Yes 

Analytica Chimica Acta
ISSN: 0003-2670
EISSN: 1873-4324 

76 

A variation of the application of Landolt type reactions for carrying out kinetic determinations of catalysts was assessed. In Landolt reactions, a slow reaction was connected to a fast reaction by the product of the slow reaction. In the variation, one reagent and the Landolt reagent were added to the catalyst instead of adding all reagents at once. Then the oxidant was added by a motor driven burette at constant speed until the final product appeared. This speed of addition was so high that at the highest concentration of catalyst not all of the oxidant was consumed. More oxidant was added until all free product catalyst was in the system. The two reactions occurred one after the other rather than simultaneously. Molybdenum (7439987), copper (7440508), and vanadium (7440622) were determined using Landolt reactions. Iodide was the reactant in all cases. Sodium-thiosulfate was the Landolt reagent in the molybdenum solution and ascorbic-acid was used with copper and vanadium. Vanadium, copper, and molybdenum determinations found using this application were within the range of the values expected.