咔唑加氢性能研究

咔唑是一种含氮的芳香杂环化合物,文中以Raney-Ni为催化剂,对咔唑的加氢储氢性能进行了研究。实验发现溶剂、温度、压力及催化剂用量等条件的改变均对咔唑的吸氢过程产生影响。溶剂十氢萘的加入有利于咔唑加氢反应进行;在443—563 K咔唑的加氢量随着温度的上升呈现先增加后减小的趋势,并在523 K达到最大值;在3MPa—6 MPa咔唑的加氢量随压力的增大而增大;催化剂用量的增加在低用量范围内明显影响咔唑的吸氢量,在高用量范围内对咔唑吸氢量的影响不大。在咔唑/十氢萘质量比为1/5.9,523 K,5 MPa和催化剂用量为0.5 g的条件下,咔唑的加氢量达到较佳值0.27 mol。GC-MS分析结果表明:咔唑的加氢产物以四氢咔唑、十二氢咔唑为主,此外还含有少量的六氢咔唑及八氢咔唑。

Study on hydrogen uptake properties of carbazole

Carbazole is one of the nitrogen-substituted organic heteroaromatic compounds and is a possible candidate for hydrogen storage.Hydrogenation reaction of carbazole over the Raney-Ni catalyst was investigated.It shows that solvent,temperature,pressure and the dosage of catalyst have distinct effect on the hydrogen uptake properties of carbazole.The amount of absorbed hydrogen showed the trend of first increase and then decrease with the rise of temperature in the range of 443-563 K,and reached maximum at 523 K;the amount of absorbed hydrogen increased with the rise of the reaction pressure in the range of 3-6 MPa;catalyst dosage significantly affected the hydrogen absorbing amount in low dosage range but made little difference in the high dosage range;the amount of absorbed hydrogen could achieve a considerable optimum value of 0.27 mol under the condition of 523 K,5 MPa and Raney-Ni 0.5 g when the mass ratio of carbazole/declain was 1/5.9.The GC/MS analysis of the liquid samples from the hydrogenation reactions confirmed the main production of tetrahydrocarbazole,dodecahydrocarbazole and small amounts of hexahydrocarbazole and octahydrocarbazole.