Patents by Inventor Cheung K. Li Kwok Cheong

Cheung K. Li Kwok Cheong 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).

  • Waste acid recovery process
    Patent number: 5082645
    Abstract: A process for the recovery of sulphuric acid from a waste acid stream containing ammonium sulphate comprising vaporizing the waste acid and subsequently converting the ammonia and sulphur dioxide generated to nitrogen and sulphur trioxide, respectively. The process provides an economic method for the regeneration of the waste sulphuric acid from a methyl methacrylate production process.
    Type: Grant
    Filed: August 24, 1990
    Date of Patent: January 21, 1992
    Assignee: Chemetics International Company, Ltd.
    Inventors: Riad A. Al-Samadi, Cheung K. Li Kwok Cheong