Date of Award
Master of Science (MS)
Adsorption behavior of the anionic collector salicyl hydroxamic acid (SHA) on a group of selected rare earth phosphates (REPs) was studied by means of experimental methods and modeling software. These REPs were then compared to rare earth carbonates (RECs) and rare earth oxides (REOs) to develop a trend. A suite of rare earth elements (REE) were studied that included light (LREE) and middle (MREE). Results for heavy (HREE) were inferred. Synthetic phosphate, oxide and carbonate powders of the rare earth elements Lanthanum (La), Cerium (Ce), Europium (Eu) and Dysprosium (Dy) were tested for these studies. Dysprosium phosphate was the only REE that was synthesized in the lab for further testing. The studies were conducted at a range of pH levels to mimic commercial flotation processes and to optimize recovery parameters involving the collector SHA. Differences in adsorption behavior between LREE, and MREE as well as HREE are attributed to solution chemistry, coordination number and REEionic diameter. SHA adsorption follows an ion-exchange process that leads to chemisorbed or surface precipitated states, depending on atomic spacing and pH level. These effects are strongly attributed to lanthanide contraction.
Trant, Stephanie, "COMPARISON OF SALICYL HYDROXAMATE ADSORPTION ON RARE EARTH PHOSPHATES TO OXIDES AND CARBONATES" (2018). Graduate Theses & Non-Theses. 192.