负载型Co-Rh/γ-Al_2O_3催化剂催化(R)-2-氨基-1-丁醇的消旋反应

在固定床反应器内,将负载型Co-Rh/γ-Al2O3催化剂(简称催化剂)用于催化(R)-2-氨基-1-丁醇的消旋反应,系统地考察了反应压力、反应温度、(R)-2-氨基-1-丁醇水溶液的含量及进料流量对催化剂性能的影响,同时考察了催化剂的稳定性,并对反应机理进行了初步探讨。实验结果表明,所研制的催化剂具有很好的催化活性和选择性。在反应温度150℃、反应压力3．0 MPa、(R)-2-氨基-1-丁醇水溶液的质量分数20％、进料流量1．0 mL／min的条件下,(R)-2-氨基-1-丁醇的消旋率为100％,(R,S)-2-氨基-1-丁醇的回收率为89．6％。该催化剂具有良好的稳定性,经过30d的连续使用,催化剂仍具有良好的催化性能,未发现明显失活现象。(R)-2-氨基-1-丁醇消旋反应的机理为脱氢-加氢的反应机理。

Racemization of(R) -2-Amino-1-Butanol Catalyzed by Supported Co-Rh/γ-Al2O3

(S)-2-Amino-1-butanol,used as an important medicine intermediate,was produced mainly through resolution of racemic(R,S)-2-amino-1-butanol,in which the unwanted(R)-2-amino-1-butanol was recycled for further racemization. In previous studies, racemization of (R)-2-amino-1-butanol required presence of ammonia which caused the process hard to be controlled, or could only operate batch. In this paper, racemization of (R)-2-amino-1-butanol was carried out over supported Co-Rh/γ-Al2O3 catalyst in a fixed-bed reactor. The activity,selectivity, stability and reaction mechanism of this catalyst were investigated. Effects of pressure, temperature, concentration of the solution and feed rate on racemization were studied. The mechanism of racemization of (R)-2-amino-1-butanol was mainly dehydrogenation-hydrogenation in presence of hydrogen and transition metal catalyst. At 150℃, 3.0MPa,mass fraction of (R)-2-amino-1-butanol in aqueous solution 20% , and feed rate 1. 0 mL/ min,conversion of(R)-2-amino-1-butanol and recovery rate of(R,S)-2-amino-1-butanol were 100% and 89. 6% , respectively. The catalyst was not obviously deactivated after being used for 30 d. The catalyst could be used in commercial production of (5)-2-amino-l-butanol.