CMI Technologies with Separations

CMI researchers have created many invention disclosures and filed dozens of patent applications. This page lists technologies related to separations, which also are on the complete list of CMI invention disclosures. These are available for licensing. For CMI technology transfer, licensing or commercial inquiries, please contact Stacy Joiner at the Ames Laboratory 515-294-5932 or

  • Extraction of Rare Earth Elements from Phosphoric Acid Streams
    link to licensing information
    This invention affords the quantitative extraction of rare earths present in phosphoric acid streams produced in phosphoric acid plants.
  • Membrane Solvent Extraction for Rare Earth Separations
    Patent issued March 2018, #9,968,887 | Licensed | link to licensing information
    This invention is a membrane‐based dispersion‐free supported liquid membrane solvent extraction (MSX) for the separation, concentration and recovery of rare earth elements.
  • Methods of Separating Lithium-Chloride from Geothermal Brine Solutions
    Patent issued April 2019, #10,266,915 | link to licensing information
    This invention affords the quantitative extraction of rare earths present in phosphoric acid streams produced in phosphoric acid plants.
  • Task Specific Ionic Liquids Extractive Metallurgy or Rare Earth Minerals
    Patent application filed | link to licensing information
    Extractive metallurgy invention dissolves rare earth element containing minerals important in the United States as well as metal oxides and metal carbonates. Direct contact between rare earth minerals of interest and the invented materials may be performed, resulting in an enrichment of the medium and heavy rare earth elements, thus allowing for an attractive pre-concentration process. In this metallurgical process, the primary constituents (La, Ce, Nd) may be effectively separated from minor constituents (Eu, Tb, Dy, Ho, Y).
  • Selective Chemical Separation of Rare-Earth Oxalates (CSEREOX)
    Patent issued August 2021 #11,090,579 | link to licensing information
    This invention provides a new selective chemical separation method of rare earth oxalates with following advantages:  
    1) Chemical separation of lanthanide oxalates within two groups: La-Sm (low-priced) and Gd-Lu (high-priced).  
    2) Simple and fast: (a) no special equipment or extreme synthetic conditions are required for the extractant preparation; (b) it is an ‘one step’ separation process which takes a few minutes.
    3) Environmental Aspects: (a) It is a water-based process (no mineral acids or organic 2nd phase required); (b) The best base candidate for an extractant system, 1-methylimidazole, is recognized by Sigma-Aldrich Company as a Greener Alternative Product, which adheres to one or more of the "12 Principles of Green Chemistry." 
    4) Cost effective: The required materials (oxalic acid and the respective base) as well as the whole process are cheaper compared to the state-of-art solvent extraction with organophosphorus compounds.
    5) The separation process represents a substantial improvement to known separation technology.
  • Chemical Separation of Terbium Oxide (SEPTER)
    Patent issued July 2018 #10,029,920 | link to licensing information
    This invention provides an exceptional separation method for terbium oxide with the following advantages:  
    1) Improvement and known separation and recycling technologies:  separation of terbium (III, IV) oxide using an aqueous solution of acetic acid.
    2) Time-effective:  unprecedented dissolution rate (total about 15 to 20 minutes).
    3) Environmentally-friendly process:  water-based, omits of auxiliary hazardous chemicals; no waste generation (obtained acetates can be calcinated like the currently used oxalates).
    4) Cost effective:  required materials (solution of acetic acid=”concentrated vinegar”) and whole process including microwave heating is cheaper compared to the solvent extraction.
    5) A purity of 99.5% can be reached for the separated terbium oxide.
  • The Separation of Ancylite by Way of Magnetic Separation and Froth Flotation
    Patent application filed
    Ancylite, a rare earth strontium carbonate, is a potentially commercial rare earth mineral. In this research its properties were investigated to develop a proper procedure to efficiently separate rare earth minerals from their gangue minerals. Fundamental understanding of the flotation chemistry for ancylite, calcite and strontianite has delineated the strategy of flotation chemistry for the material. Magnetic separation combined with flotation was employed to beneficiate ancylite, and a preliminary evaluation was conducted as well. The practical result shows the promising potential in the separation of ancylite by way of magnetic separation and froth flotation.
  • Recovering Rare Earth Metals using Bismuth Extractant
    Patent issued June 2019 #10,323,299 | link to licensing information
    This invention involves a liquid metal extraction technique for treating rare earth metal-bearing permanent magnet scrap, waste, and other material to recover at least one of the light rare earth metal(s) and the heavy rare earth metal(s) for reuse in the manufacture of permanent magnets.  It can be used to treat a wide variety of binary, ternary, and other rare earth-transition metal alloy compositions.  This method can be practiced to recover the light rare earth metal content and the heavy rare earth metal content concurrently in a one-step process or separately and sequentially in a two-step process.  Unlike other processes, this method extracts both the light and heavy rare earth metals in a single extraction step.  Specifically, the heavy rare earths can be extracted very effectively using this method, which is not feasibly using other liquid metal techniques.
  • Acid-free Dissolution and Separation of Rare-earth Metals
    Patent issued May 2020 #10,648,063link to licensing information
    This invention is a simple, in-expensive and environmentally friendly chemical dissolution method for recycling NdFeB magnets.  This invention has the following advantages:  
    1) Novelty and Purity of the separated lanthanide oxides achieved ~99%.  This purity can be further improved if the materials are subjected to a second separation cycle.
    2) Time efficient: This direct dissolution process requires less time than the current state-of-the-art process.
    3) Environmentally-friendly:  This process limits the need for acids.
    4) Cost effective:  This invention requires and inexpensive salt solution.  The separation process is simple and requires no complex systems or equipment.  It can be easily incorporated into existing manufacturing or separation processes.
  • A Process for the Recovery of Mercury and Rare Earth Elements from Used Fluorescent Lamps
    Patent issued January 2020 #10,533,239 | link to licensing information
    The invention teaches an integrated process to safely separate and remove mercury and rare earth elements from fluorescent light bulbs.  The process does not rely on heating or volatilizing the mercury.  Each step in the process is fully integrated into a single, continuous process that can be run either in batch, semi-batch, or continuous-flow mode for the recovery of mercury and rare earths from fluorescent light bulbs.
  • Production of Indium Concentrate from Waste LCD Screens
    Provisional Patent Application Filed | link to licensing information
    This invention is a method to recover and liberate indium from flat panel displays.
  • Rare Earth, Thorium, and Uranium Extraction/Separation
    Patent issued June 2021 #11,040,296
    This invention pertains to a solvent extraction system that extracts rare earth elements. The organic system successfully extracts rare earth elements, and the metal loaded organic system can be completely stripped. When applied to systems containing thorium and uranium as well as rare earth elements, the system can be tuned for selective extraction of the rare earth elements over thorium and uranium.
  • An Electrotwinning Process for Recovering High Purity Rare Earth Metals from Room Temperature Ionic Liquids
    The invention describes a process for electrowinning rare earth metals by augmenting a room temperature ionic liquid with a secondary, tertiary, quaternary, etc. component (gas, liquid, salt, or supercritical fluid).
  • Surface Chemistry and Novel Collectors and their Application to Rare Earth Minerals
    Patent application filed
    This invention is the successful development and application of novel collectors for rare earth mineral flotation.  Novel collectors enhance TREO recovery, grade and gangue rejection in flotation. Also, much of the testing was performed at ambient temperature and without the use of depressants, which is an advantage over existing industrial rare earth flotation systems.
  • Precipitation of Rare Earth Carbonates using Monoethanolamine
    Patent application filed
    A new means of precipitating rare earth carbonates from aqueous solutions at industrially relevant concentrations. The process utilizes aqueous solutions of monoethanolamine fully loaded with carbon dioxide to deplete aqueous rare earth salt solutions with greater than 99 percent yield; the remaining filtrate contains monoethanolamine – hydrogen chloride and is easily separated from the precipitate.
  • Neutral Ligand Room Temperature Ionic Liquid System for Electrodeposition of Rare Earth Elements
    Patent application filed
    Using a common industrial organic solvent, it is possible to synthesize neutral ligand room temperature ionic liquids (RTILs) for rare earth elements.  These RTILs have excellent electrochemical properties and can be used to successfully deposit rare earth metals.
  • Electrochemical Separation System for the Efficient Co-recycle of Li from Li Ion Batteries
    This technology aims to include an electrochemical process as key element in the hydrometallurgical recovery of value metals (i.e. Co, Mn, and Li) from Li ion batteries. This concept consists in the inclusion of an electrochemical separation step based on the use of a selective membrane and a re-generable carbon source for the production of high purity Li2CO3.
  • Two-Stage Removal of Selenium from Copper Smelter Stack Wash
    This invention is a two-stage polishing process that results in the removal of interfering soluble selenium (selenious acid, H2SeO3) from the acidic stack wash of copper smelters, making the resulting solution ideal as an ion exchange feed solution from which the critical metal rhenium can be isolated, concentrated, and eluted as a product.
  • Reengineered Sorbents for Li Extraction from Ambient Temperature Geothermal Brine
    LiCl.2Al(OH)3.nH2O, LDH has been identified as an effective sorbent for selective extraction of lithium from brines.  However, LDH is suitable for only high temperature (possibly 80-125 °C) brine solution. Our concept is to use novel type sorbents in a column extraction.
  • A New Electrolyte System for the Preparation of Rare Earth Elements
    Three new electrolyte systems were investigated to examine the possibility of electrodepositing individual rare-earth elements. Although all the three electrolytes (one unitary, one binary and one ternary) showed good results for depositing these elements, the ternary electrolyte showed a significant advantage in terms of obtaining metallic deposits at a much lower operating temperature. The present invention discloses the use of the new electrolyte systems not just for electrodepositing rare-earth elements but also for carrying out electroplating, electrorefining of oxidized products and developing a new surface-diffusion process to fabricate novel materials.
  • Selective Recovery and Concentration of Lithium Chloride with Composite Membranes
    Patent application filed
    The membrane-based selective Li extraction and concentration can potentially address the issue of recovering Li from geothermal brines with a lithium/aluminum layered double hydroxide-based sorption system that requires further concentration, which concentrates both the desired elements and undesirable impurities.
  • Engineered Microbes for Rare Earth Element Adsorption
    Engineered bacterial strains of Caulobacter crescentus and Escherichia coli, that express lanthanide binding tag (LBT) on cell surface proteins, showed enhanced ability to sequester rare earth elements through bio-absorption.
  • Lithium Extraction from Geoghermal Brine Solutions via Nanoengineered Polymer Composite Sorbent Bead
    The invention relates to a lithium sorbent for extracting lithium.
  • Diglycolamide Derivatives for Improved Separation and Recovery of Rare Earth Elements
    Discovery is diglycolamide derivatives that exhibit improved separation and recovery of rare earth elements, which can result in significant cost savings and, therefore, will encourage production of REEs domestically.
  • A Novel Bio-Based Material for Rare Earth Element Separation
    Patent issued August 2023 #11,713,493 link to pdf
    A bio-based rare earth element separation technology consisting of lanthanide binding tag-displayed E. coli and/or C. crescentus cells encapsulated within a polymer matrix and used as a column chromatography resin that enables a continuous flow system for the separation of individual REEs from aqueous REE-containing feedstocks. 
  • Chemical Formulation to Leach Palladium Bearing Materials
    Patent application filed
    Method can operate at room temperature and shows rates that are similar to those performed at much higher temperatures to recover palladium from catalysts and electronic devices.
  • Recovery of Cobalt from End-of-Life Lithium Batteries with Supported Membrane Solvent Extraction
    Cobalt is a critical material, substantially and increasingly used in the lithium ion batteries, which are considered as an important secondary resource for the extraction and recovery of cobalt. The recycling and reuse of the cobalt from lithium ion batteries is important for the sustainability of the clean energy industry.
  • Selective Removal of Sodium and Potassium Contaminants from Lithium Chloride Brine Using Liquid-Liquid Separation
    Use liquid-liquid extraction separation to selectively remove sodium cation and potassium cation from solution containing lithium chloride, which increased the purity of the resultant lithium chloride solution.
  • Selective Extraction of Lithium from Hot Leachate Sulfate Stream Through a Precipitation Process 
    The invention provides a method to selectively extract lithium from leachate solution.
  • Selective Extraction of Lithium from Lithium Containing Brines
    The invention provides a method for extracting lithium from lithium containing solutions.