Patents by Inventor Yaw Jong Liu

Yaw Jong Liu 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).

  • Method for recovering and producing C4-C6 dicarboxylate from alkaline waste solution generated in caprolactam preparation process
    Patent number: 6825379
    Abstract: The present invention relates to a method for recovering and producing C4-C6 dicarboxylates from an alkaline waste solution generated in a caprolactam preparation process, in which the alkaline waste solution is treated with sulfuric acid to separate into an aqueous phase and an organic phase, allowing valuable substances contained in the organic phase to be firstly oxidized and converted into dicarboxylic acids. The dicarboxylic acids then undergo concentration, esterification and distillation processes, so as to obtain desirable C4-C6 dicarboxylates with high purity. This therefore provides an efficient and improved method for effectively recovering most valuable substances from the alkaline waste solution, so that economic benefits in recovery are greatly raised.
    Type: Grant
    Filed: January 14, 2002
    Date of Patent: November 30, 2004
    Assignee: Chemaxz International Corporation
    Inventors: Sien-Chun Chou, Edward K. S. Wang, Chung Ho Wu, Yaw Jong Liu, Ping Chiang
  • Method for recovering and producing C4-C6 dicarboxylate from alkaline waste solution generated in caprolactam preparation process
    Publication number: 20030045750
    Abstract: The present invention relates to a method for recovering and producing C4-C6 dicarboxylates from an alkaline waste solution generated in a caprolactam preparation process, in which the alkaline waste solution is treated with sulfuric acid to separate into an aqueous phase and an organic phase, allowing valuable substances contained in the organic phase to be firstly oxidized and converted into dicarboxylic acids. The dicarboxylic acids then undergo concentration, esterification and distillation processes, so as to obtain desirable C4-C6 dicarboxylates with high purity. This therefore provides an efficient and improved method for effectively recovering most valuable substances from the alkaline waste solution, so that economic benefits in recovery are greatly raised.
    Type: Application
    Filed: January 14, 2002
    Publication date: March 6, 2003
    Applicant: CHEMAX INTERNATIONAL CORPORATION
    Inventors: Sien-Chun Chou, Edward K.S. Wang, Chung Ho Wu, Yaw Jong Liu, Ping Chiang