Abstract: Recovery of cerium values from fluoride-containing ores such as bastnasite is enhanced. The ore is ground, roasted, and leached with dilute hydrochloric acid to produce an ore concentrate. The concentrate is treated with a solution of hydrochloric acid and boric acid to solubilize cerium values and convert fluoride to tetrafluoroborate ion. Tetrafluoroborate is removed from the solution, e.g., by precipitation, and the solution is further processed for recovery of cerium values. Removal of tetrafluoroborate avoids loss of cerium as insoluble cerium tetrafluorborate during said further processing.

Abstract: Recovery of cerium values from fluoride-containing ores such as bastnasite is enhanced. The ore is ground, roasted, and leached with dilute hydrochloric acid to produce an ore concentrate. The concentrate is treated with a solution of hydrochloric acid and boric acid to solubilize cerium values and convert fluoride to tetrafluoroborate ion. Tetrafluoroborate is removed from the solution, e.g., by precipitation, and the solution is further processed for recovery of cerium values. Removal of tetrafluoroborate avoids loss of cerium as insoluble cerium tetrafluorborate during said further processing.

Abstract: A process for upgrading technical low grade cerium/fluorine-containing residues having concentrations of silicon and iron above about 1.0 weight percent produces compositions wherein the combined silicon and iron content is less than about 1.0 weight percent. Typically, the cerium content is raised to above about 50 weight percent and sufficient fluorine is present for the fluorine-to-cerium molar ratio to be 3.0 or above. Lubricating compositions comprising a major part of a lubricant and a minor amount of said upgraded cerium/fluorine-containing residue are useful as anti-wear lubricants.

Abstract: Chromatographic species are continuously separated by either elution or displacement HPLC using an apparatus that comprises a stationary inlet distribution manifold, a stationary chromatographic bed, and mobile collector receptacles.

Abstract: Fused polynuclear aromatic compounds (PNAs) are continuously removed from a recycle oil stream in a hydrocracking process. An adsorption bed removes the PNAs from the recycle oil, a desorbing reagent removes the PNAs from the bed, and a regenerating agent regenerates the bed, all steps being performed simultaneously and continuously.

Abstract: Chlorine is removed from a gas stream by contacting the stream with a pulverized, oxidized bastnasite ore in the presence of water. The invention is particularly applicable to the processing of bastnasite ore for the recovery of rare earth compounds wherein there is produced a waste gas stream containing chlorine.