Patents Assigned to WANHUA CHEMICAL GROUP CO., LTD.
  • Patent number: 8829245
    Abstract: Provided is a 3-aminomethyl-3,5,5-trimethylcyclohexylamine preparation method. A feeding flow of 3-cyano-3,5,5-trimethylcyclohexylamine is reacted with NH3 and hydrogen in the presence of a hydrogenation catalyst; the method is characterized by: firstly adding a basic compound to the feeding flow of 3-cyano-3,5,5-trimethylcyclohexylamine, and then after a portion of 3-cyano-3,5,5-trimethylcyclohexylamine has reacted, adding an acidic compound to reaction materials for further hydrogenation reaction to prepare the product. The method ensures that the aminonitrile content in the product is low, thus effectively reducing the duration of the reaction and greatly reducing the consumption of the catalyst during the hydrogenation reaction process.
    Type: Grant
    Filed: September 6, 2011
    Date of Patent: September 9, 2014
    Assignees: Wanhua Chemical Group Co., Ltd., Wanhua Chemical (Ningbo) Co., Ltd.
    Inventors: Changsheng Chen, Yuan Li, Wenjuan Zhao, Hongyin Cui, Weiqi Hua
  • Patent number: 8759591
    Abstract: The present invention discloses a method for intermittently producing 4,4?-diaminodicyclohexyl methane (H12MDA) with a low amount of the trans-trans isomer thereof, which comprises: controlling the reaction process by stopping the reaction when, except for a solvent, the reaction solution comprises MDA of 0-5 wt % and H6MDA of 1-20 wt %; and b) separating the reaction solution obtained from step a) by conventional means to obtain H12MDA product with desired purity, and allowing the un-reacted material and intermediate product to be recycled to the reactor after being accumulated. The method of the present invention decreases the amount of the trans-trans isomer in H12MDA, increases the yield of the reaction, and reduces the production cost. The present invention also provides a post treatment process of the reaction mixture.
    Type: Grant
    Filed: June 3, 2011
    Date of Patent: June 24, 2014
    Assignees: Wanhua Chemical Group Co., Ltd., Wanhua Chemical (Ningbo) Co., Ltd.
    Inventors: Shuang Hu, Hao Chen, Zilin Ni, Wangshun Qi, Zhongying Chen, Zhiyuan Liu, Xudong Wang, Zhanyu Zhao, Weiqi Hua
  • Publication number: 20140142341
    Abstract: Provided is a 3-aminomethyl-3,5,5-trimethylcyclohexylamine preparation method. A feeding flow of 3-cyano-3,5,5-trimethylcyclohexylimine is reacted with NH3 and hydrogen in the presence of a hydrogenation catalyst; the method is characterized by: firstly adding a basic compound to the feeding flow of 3-cyano-3,5,5-trimethylcyclohexylimine, and then after a portion of 3-cyano-3,5,5-trimethylcyclohexylimine has reacted, adding an acidic compound to reaction materials for further hydrogenation reaction to prepare the product. The method ensures that the aminonitrile content in the product is low, thus effectively reducing the duration of the reaction and greatly reducing the consumption of the catalyst during the hydrogenation reaction process.
    Type: Application
    Filed: September 6, 2011
    Publication date: May 22, 2014
    Applicants: Wanhua Chemical (Ningbo) Co., Ltd., WANHUA CHEMICAL GROUP CO., LTD.
    Inventors: Changsheng Chen, Yuan Li, Wenjuan Zhao, Hongyin Cui, Weiqi Hua
  • Publication number: 20130288884
    Abstract: The present invention relates to a catalyst for producing chlorine by oxidation of hydrogen chloride and a method for preparing the same. The catalyst comprises a support and active ingredients that comprise 1-20 wt % of copper, 0.01-5 wt % of boron, 0.1-10 wt % of alkali metal element(s), 0.1-15 wt % of one or more rare earth elements, and 0-10 wt % of one or more elements selected from magnesium, calcium, barium, manganese, iron, nickel, cobalt, zinc, ruthenium or titanium based on the total weight of the catalyst. The catalyst is prepared by a two-step impregnation method. Comparing with the available catalysts of the same type, the catalyst according to the present invention has greatly improved conversion and stability.
    Type: Application
    Filed: June 3, 2011
    Publication date: October 31, 2013
    Applicants: NINGBO WANHUA POLYURETHANES CO., LTD., WANHUA CHEMICAL GROUP CO., LTD.
    Inventors: Guangquan Yi, Yinchuan Lou, Yi Wan, Xunkun Wu, Weiqi Hua, Jiansheng Ding