Embodiments relate to methods for generating selected materials from a natural brine. A natural brine comprising at least a portion of a selected material is heated. CO.sub.2 is added and mixes with the natural brine forming a mixture such that the CO.sub.2/P is a first predetermined value. The mixture is held so that impurities in the natural brine precipitate as solids leaving a second brine substantially comprising the selected material. The second brine is heated. CO.sub.2 gas is injected into the second brine, mixing so that the CO.sub.2/P is a second predetermined value. The mixture is held so that the selected material precipitates out and are removed.

Embodiments relate to methods for generating selected materials from a natural brine. A natural brine comprising at least a portion of a selected material is heated. CO.sub.2 is added and mixes with the natural brine forming a mixture such that the CO.sub.2/P is a first predetermined value. The mixture is held so that impurities in the natural brine precipitate as solids leaving a second brine substantially comprising the selected material. The second brine is heated. CO.sub.2 gas is injected into the second brine, mixing so that the CO.sub.2/P is a second predetermined value. The mixture is held so that the selected material precipitates out and are removed.

Mixed rare earth carbonate may be prepared by mixing a rare earth sulfate solution with a precipitating agent comprising a first sodium carbonate (Na.sub.2CO.sub.3) solution, to form a first mixture, and generating a higher sulfate rare earth carbonate wet cake from the first mixture. The higher sulfate rare earth carbonate wet cake can be mixed with a second sodium carbonate (Na.sub.2CO.sub.3) solution to form a second mixture, and a lower sulfate rare earth carbonate can be generated from the second mixture.

Mixed rare earth carbonate may be prepared by mixing a rare earth sulfate solution with a precipitating agent comprising a first sodium carbonate (Na.sub.2CO.sub.3) solution, to form a first mixture, and generating a higher sulfate rare earth carbonate wet cake from the first mixture. The higher sulfate rare earth carbonate wet cake can be mixed with a second sodium carbonate (Na.sub.2CO.sub.3) solution to form a second mixture, and a lower sulfate rare earth carbonate can be generated from the second mixture.

The invention relates to a system and a method for the processing of minerals containing the lanthanide series and the production of rare earth oxides, which allow a completely closed and continuous treatment of the different materials and desorbent agents involved in the process, thus improving the efficiency in the extraction and avoiding environmental risks associated. The method comprising the steps of: reception and conditioning of the raw material; desorption of valuable product through a plurality of mixing and reaction stages in which the raw material is contacted in countercurrent with a stream of desorbent solution; separation of fine solids; precipitation of secondary minerals through the use of a first reactive solution; precipitation of rare earth carbonates through the use of a second reactive solution; and drying and roasting of the rare earth carbonates to obtain rare earth oxides; wherein the method further comprises a secondary process that allows further processing of the residual mineral, and a dewatering and washing step wherein the residual mineral from the desorption step is washed and a lanthanide-containing liquid is recovered.

Nanosheets of Ca.sup.2+ and Y.sup.3+, with CO.sub.3.sup.2− in the interlayer with a uniform diameter and lengths of several tens of microns have been successfully synthesized in a hydrotalcite layer structure (a layered double hydroxide), using a hydrothermal method. The formation mechanism of lamellar CaY—CO.sub.3.sup.2− layered double hydroxides (LDHs) depends on the molar ratio of Ca and Y and the reaction time and temperature. The resulting LDH materials exhibit excellent affinity and selectivity for heavy transition metal and metalloid ions.

Nanosheets of Ca.sup.2+ and Y.sup.3+, with CO.sub.3.sup.2− in the interlayer with a uniform diameter and lengths of several tens of microns have been successfully synthesized in a hydrotalcite layer structure (a layered double hydroxide), using a hydrothermal method. The formation mechanism of lamellar CaY—CO.sub.3.sup.2− layered double hydroxides (LDHs) depends on the molar ratio of Ca and Y and the reaction time and temperature. The resulting LDH materials exhibit excellent affinity and selectivity for heavy transition metal and metalloid ions.

The present invention is a method of producing a lanthanum carbonate hydroxide or lanthanum oxycarbonate which has improved properties. The method involves the use of a water soluble lanthanum and a water soluble non-alkali metal carbonate or bicarbonate. The resulting material can be used as a phosphate binder individually or for treating patients with hyperphosphatemia.

The present invention is a method of producing a lanthanum carbonate hydroxide or lanthanum oxycarbonate which has improved properties. The method involves the use of a water soluble lanthanum and a water soluble non-alkali metal carbonate or bicarbonate. The resulting material can be used as a phosphate binder individually or for treating patients with hyperphosphatemia.

The disclosure provides, inter alia, formulations comprising cerium (III) carbonate, and processes for producing cerium (III) carbonate. In embodiments, the disclosure provides methods for passivating photodegradation of organic compounds using cerium (III) carbonate.