Wanhua Chemical Group Co., Ltd.

Wanhua Chemical (Ningbo) Co., Ltd.

Zhanyu Zhao

Weiqi Hua

Hao Chen

Zhongying Chen

Wangshun Qi

Shuang Hu

Zilin Ni

Zhiyuan Liu

Xudong Wang

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.

Method for intermittently producing 4,4'-diaminodicyclohexylmethane with a low amount of the trans-trans isomer

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Yantai, China

Zhanyu Zhao