Patents Assigned to Lenroc Company
  • Patent number: 8067587
    Abstract: A process for making monoalkali metal cyanurates in a powdery form from a cyanuric acid powder by adding thereto a concentrated aqueous solution of an alkali hydroxide such as sodium or potassium hydroxide. The concentrated aqueous alkali hydroxide solution is added sequentially to the cyanuric acid powder as the admixture is vigorously mixed, forming a monoalkali metal cyanurate as a hydrated powder.
    Type: Grant
    Filed: July 28, 2006
    Date of Patent: November 29, 2011
    Assignee: Lenroc Company
    Inventors: Kurt F. Stephan, Brandon K. Stephan
  • Patent number: 4894452
    Abstract: The process of producing from urea a reaction product which is predominantly cyanuric acid, which process involves only the application of heat without use of solvents or catalysts. The process in its first stage involves heating molten urea for a time and at a temperature to convert the urea to a first stage reaction product comprising less than 40% urea and at least 30% biuret, then cooling and comminuting the first stage reaction product, then as a second stage of the process, passing hot air through the comminuted first stage reaction product at temperatures progressively increasing but maintained below the melting point of the reaction, such solid phase heating of the reaction product during the second stage of the process being maintained until the cyanuric acid content is at least about 50% of the final reaction product and is preferably at least about 70%.
    Type: Grant
    Filed: April 18, 1988
    Date of Patent: January 16, 1990
    Assignee: Lenroc Company
    Inventor: Kurt F. Stephan