Abnormal mode of phosphate adsorption on microcrystalline lead iodate

The dependence of instantaneous uptake of radioactive phosphate species on ignited lead iodate has been studied as a function of pH and the ionic composition of the suspension medium. As expected, an increase in the carrying is observed with a rise in pH and the concentration of cationic species. However, nonlattice cations (e.g. barium, strontium ions) with similar electric charge and ionic dimensions show abnormal influence. The observed drop in the presence of these non-lattice cations is attributed to the possible reduction in the active sites of the carrier which is postulated to be responsible for the deposition. Conclusions regarding the nature of the processes responsible for the uptake are drawn. (author)