Patents by Inventor Tonghe LI

Tonghe LI 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).

  • Patent number: 11814339
    Abstract: A method for preparing an isocyanate in a gaseous phase by feeding, in the presence or absence of an inert gas, an amine-containing gas stream and a phosgene-containing gas stream into a reaction region, allowing the amine and the phosgene to contact in gaseous forms and undergo a phosgenation reaction in the reaction region, thus preparing the target isocyanate in a gaseous form in the reaction region. The phosgene-containing stream is subjected to preheating and warming before being fed into the reaction region, and the phosgene-containing stream comprises a substance A at a mass fraction of <1% before being subjected to the preheating and warming up. Substance A is a NCO group-containing substance and/or an olefinic double bond-containing substance. The method reduces the formation of clogging matter in a heat exchanger and a vessel during the preheating and warming of the phosgene and during the reaction process.
    Type: Grant
    Filed: December 26, 2018
    Date of Patent: November 14, 2023
    Assignees: WANHUA CHEMICAL GROUP CO., LTD., WANHUA CHEMICAL (NINGBO) CO., LTD.
    Inventors: Weiqi Hua, Tonghe Li, Yonghua Shang, Shuchang Sun, Jingxu Wang, Jinping Han, Qiang Li, Wenbin Li, Jing Li, Pengfei Wang, Yuan Li
  • Publication number: 20220024863
    Abstract: A method for preparing an isocyanate in a gaseous phase by feeding, in the presence or absence of an inert gas, an amine-containing gas stream and a phosgene-containing gas stream into a reaction region, allowing the amine and the phosgene to contact in gaseous forms and undergo a phosgenation reaction in the reaction region, thus preparing the target isocyanate in a gaseous form in the reaction region. The phosgene-containing stream is subjected to preheating and warming before being fed into the reaction region, and the phosgene-containing stream comprises a substance A at a mass fraction of <1% before being subjected to the preheating and warming up. Substance A is a NCO group-containing substance and/or an olefinic double bond-containing substance. The method reduces the formation of clogging matter in a heat exchanger and a vessel during the preheating and warming of the phosgene and during the reaction process.
    Type: Application
    Filed: December 26, 2018
    Publication date: January 27, 2022
    Inventors: Weiqi HUA, Tonghe LI, Yonghua SHANG, Shuchang SUN, Jingxu WANG, Jinping HAN, Qiang LI, Wenbin LI, Jing LI, Pengfei WANG, Yuan LI