The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 24, 2014
Filed:
Jun. 03, 2011
Shuang HU, Yantai, CN;
Hao Chen, Yantai, CN;
Zilin NI, Yantai, CN;
Wangshun Qi, Yantai, CN;
Zhongying Chen, Yantai, CN;
Zhiyuan Liu, Yantai, CN;
Xudong Wang, Yantai, CN;
Zhanyu Zhao, Yantai, CN;
Weiqi Hua, Yantai, CN;
Shuang Hu, Yantai, CN;
Hao Chen, Yantai, CN;
Zilin Ni, Yantai, CN;
Wangshun Qi, Yantai, CN;
Zhongying Chen, Yantai, CN;
Zhiyuan Liu, Yantai, CN;
Xudong Wang, Yantai, CN;
Zhanyu Zhao, Yantai, CN;
Weiqi Hua, Yantai, CN;
Wanhua Chemical Group Co., Ltd., Yantai, CN;
Wanhua Chemical (Ningbo) Co., Ltd., Ningbo, CN;
Abstract
The present invention discloses a method for intermittently producing 4,4'-diaminodicyclohexyl methane (HMDA) 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 HMDA of 1-20 wt %; and b) separating the reaction solution obtained from step a) by conventional means to obtain HMDA 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 HMDA, increases the yield of the reaction, and reduces the production cost. The present invention also provides a post treatment process of the reaction mixture.