Patents by Inventor Ronald D. G. Crozier

Ronald D. G. Crozier has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Industrial process for the manufacture of alkyl xanthogen formates
    Patent number: 4605518
    Abstract: A batch process including a circulating reactor and an agitated reactor for the production of dialkyl xanthogen formates, including means to increase yields of products, inhibiting chloroformate hydrolysis, suppress production of xanthic anhydride as a byproduct, and generally control product/byproduct yields based on intended use. Certain product mixtures are particularly useful as flotation reagents, specifically collectors in the flotation of molybdenum-bearing copper ores, where molybdenum recovery has been increased by more than 10% without adverse effects on copper recovery.
    Type: Grant
    Filed: June 1, 1982
    Date of Patent: August 12, 1986
    Inventor: Ronald D. G. Crozier
  • Alkyl xanthogen formate mixture as flotation agent
    Patent number: 4454051
    Abstract: A batch process including a circulating reactor and an agitated reactor for the production of dialkyl xanthogen formates, including means to increase yields of products, inhibiting chloroformate hydrolysis, suppress production of xanthic anhydride as a byproduct, and generally control product/byproduct yields based on intended use. Certain product mixtures are particularly useful as flotation reagents, specifically collectors in the flotation of molybdenum-bearing copper ores, where molybdenum recovery has been increased by more than 10% without adverse effects on copper recovery.
    Type: Grant
    Filed: June 4, 1981
    Date of Patent: June 12, 1984
    Inventor: Ronald D. G. Crozier
  • Collector compositions for froth flotation and process for making same
    Patent number: 4410439
    Abstract: Dialkyl xanthogen formates are known collectors, but the reaction that produces them, between an alkaline alkyl xanthate and an alkaline chloroformate, also causes side reactions which produce varying amounts of xanthic anhydride, carbonyl sulfide and dialkyl carbonate as by-products, and yield of formate may be as low as 30%. There are here disclosed processing schemes for controlling the amount and type of products and by-products produced in the reaction, and flotation tests show that certain product mixtures are significantly improved collectors for sulfide ores.
    Type: Grant
    Filed: July 14, 1982
    Date of Patent: October 18, 1983
    Inventor: Ronald D. G. Crozier
  • Process for producing alkyl xanthogen alkylformates
    Patent number: 4354980
    Abstract: Dialkyl xanthogen formates are known collectors, but the reaction that produces them, between an alkaline alkyl xanthate and an alkaline chloroformate, also causes side reactions which produce varying amounts of xanthic anhydride, carbonyl sulfide and dialkyl carbonate as by-products, and yield of formate may be as low as 30%. There are here disclosed processing schemes for controlling the amount and type of products and by-products produced in the reaction, and flotation tests show that certain product mixtures are significantly improved collectors for sulfide ores.
    Type: Grant
    Filed: June 4, 1981
    Date of Patent: October 19, 1982
    Inventor: Ronald D. G. Crozier