公开(公告)号：US5254729A

公开(公告)日：1993-10-19

申请号：US705363

申请日：1991-05-24

申请人： Kenji Fujiwara ,  Susumu Yoshinaga ,  Yuji Matsuu ,  Hiroshi Kato ,  Atsuhiko Hiai

发明人： Kenji Fujiwara ,  Susumu Yoshinaga ,  Yuji Matsuu ,  Hiroshi Kato ,  Atsuhiko Hiai

IPC分类号： C07C227/40 ,  C07C229/08 ,  C07C215/08

CPC分类号： C07C227/40

摘要： A method for purifying glycine characterized by comprising the steps of adjusting the pH of an aqueous glycine solution to 6 or less with a mineral acid and/or an organic acid or an acidic cation exchange resin and subsequently decoloring said aqueous glycine solution by active carbon treatment.

公开(公告)号：US5202479A

公开(公告)日：1993-04-13

申请号：US649021

申请日：1991-02-01

申请人： Kenji Fujiwara ,  Nobutaka Ueda ,  Yuji Matsuu ,  Hiroshi Kato ,  Atsuhiko Hiai

发明人： Kenji Fujiwara ,  Nobutaka Ueda ,  Yuji Matsuu ,  Hiroshi Kato ,  Atsuhiko Hiai

IPC分类号： C07C227/12 ,  C07C227/26

CPC分类号： C07C227/12 ,  C07C227/26

摘要： A process for preparing glycine which comprises the steps of reacting glycolonitrile, carbon dioxide gas, ammonia and water to obtain a reaction solution containing glycine, concentrating this reaction solution in two steps, recycling a gaseous phase portion formed in a primary concentration step to a reaction zone, and recycling to the reaction zone, a mother liquor left after glycine crystals have been separated from a concentrate obtained in a secondary concentration step.