| 摘要 |
PURPOSE:To stably obtain high-purity 1-amino-2,3-propanediol useful as a raw material for X-ray contrast medium, having low content of 2-amino-1,3- propanediol free from discoloration. CONSTITUTION:A crude solution of 1-amino-1,3-propanediol (1-APD) having >=0.30% content of 2-amino-2,3-propanediol (2-APD) based on 1-APD and preferably >=95% 1-APD purity is distilled by using a distillation column having small pressure loss of <=0.5Torr based on l theoretical plate, preferably a packed tower, especially distillation column 1-1 packed with a regular filler such as THROUSER packing, having 3-100, especially 5-30 total number of theoretical plates or a thin film evaporator, especially a raking type thin film evaporator to give high-purity 1-APD having <0.30, preferably <0.25%, especially <0.20% 2-APD based on 1-APD.
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