公开(公告)号：US09206120B2

公开(公告)日：2015-12-08

申请号：US14425310

申请日：2013-01-06

申请人： ZHEJIANG NHU COMPANY LTD. ,  ZHEJIANG UNIVERSITY ,  SHANDONG NHU AMINO ACIDS CO., LTD.

发明人： Zhirong Chen ,  Cunchao Wang ,  Chuqiu Zhao ,  Sujuan Wang ,  Chengfeng Zhang ,  Tao Long ,  Xinhong Liu

IPC分类号： C07C323/00 ,  C07C321/00 ,  C07C45/00 ,  C07C319/20 ,  C07D207/38

CPC分类号： C07C319/20 ,  C07D207/38 ,  C07C323/58

摘要： The present invention discloses a clean method for preparing a D,L-methionine comprising the steps of: preparing a potassium cyanide solution using a crystallized mother solution containing potassium carbonate as an absorbing liquid to absorb hydrocyanic acid, then reacting the potassium cyanide solution with 3-methylthio propionaldehyde and an ammonium bicarbonate solution at 50-150° C. for 3-15 minutes so as to obtain a 5-(β-methylthioethyl)glycolyurea solution, then bring the 5-(β-methylthioethyl)glycolyurea solution to a temperature of 140-220° C. and subjecting to a saponification reaction for 2-5 minutes, after the completion of the saponification, reducing the temperature to 0-40° C., extracting with an organic solvent, neutralizing the water phase with CO2 and crystallizing, then filtering, washing, and drying to obtain an acceptable D,L-methionine product; bring the crystallized D,L-methionine mother solution from filtration to a temperature to 110-160° C. to remove CO2, which are all then circulated and used as a hydrocyanic acid-absorbing liquid. The process route of the present invention is a route suitable for a continuous and clean production, substantially without producing waste water and waste gas.

摘要翻译： 本发明公开了一种制备D，L-甲硫氨酸的清洁方法，包括以下步骤：使用含有碳酸钾的结晶的母液作为吸收液体吸收氰氰酸，然后使氰化钾溶液与3 - 甲硫基丙醛和碳酸氢铵溶液在50-150℃下反应3-15分钟，得到5-（叔丁基硫代乙基）糖醇脲溶液，然后将5 - （（R） - 甲硫基乙基）糖醇脲溶液 温度为140-220℃，皂化反应2-5分钟，皂化完成后，将温度降至0-40℃，用有机溶剂萃取，中和水相用 CO 2并结晶，然后过滤，洗涤和干燥，得到可接受的D，L-甲硫氨酸产物; 将结晶的D，L-甲硫氨酸母液过滤至110-160℃，除去二氧化碳，然后循环使用，并用作氢氰酸吸收液。 本发明的工艺路线是适合连续清洁生产的路线，基本上不产生废水和废气。