Octanohydroxamic acid (OHA), the more common hydroxamate collector, has both an acid group (single bondNHOH) and basic group (single bond CO). The hydrogen in the acid group can be replaced by a metal ion and a dative bond from the basic group to form a chelate. Improved monazite flotation performance was reported when using OHA compared to the results obtained with sodium oleate. Flotation separation of monazite and calcite using OHA has been described in previous publications. OHA was the most potent urease inhibitor among saturated hydroxamic acid (HAs) with a calculated IC50 of 0.25?±?0.1?mM compared to 8.67?±?1.3 and 0.50?±?0.2?mM for Acetohydroxamic acid and heptanohydroxamic acid, respectively. Further increase in the chain length from 8 to 12 carbons negatively affected the potency of HAs[1].
