论文部分内容阅读
非晶态Ni-B催化剂具有优异的催化加氢性能,但其稳定性差限制了其推广应用。该文采用特殊结构的K2Ti6O13为载体,通过浸渍-化学还原法制备了负载型非晶态合金催化剂Ni-B/K2Ti6O13,考察其催化硝基苯加氢的性能。采用XRD、TG、TPR、比表面积-孔径分布测试对催化剂进行了表征。结果表明,在非晶态Ni-B催化剂中加入适量的K2Ti6O13稳定了催化剂表面的Ni-B物种,提高了非晶态Ni-B催化剂的活性和稳定性。Ni适宜负载量(Ni的理论质量与K2Ti6O13质量的百分比)为30%时,在反应温度为100℃、氢气分压为2.0 MPa的条件下反应120 min,硝基苯的转化率和苯胺的选择性分别可达99.5%和98.0%,并且催化剂循环使用6次后转化率和选择性分别为98.0%和93.0%。
Amorphous Ni-B catalyst has excellent catalytic hydrogenation performance, but its poor stability limits the promotion of its application. In this paper, a special structure of K2Ti6O13 as carrier was prepared by impregnation - chemical reduction of the supported amorphous alloy catalyst Ni-B / K2Ti6O13 to investigate the performance of catalytic nitrobenzene hydrogenation. The catalysts were characterized by XRD, TG, TPR and BET specific surface area. The results show that adding an appropriate amount of K2Ti6O13 to the amorphous Ni-B catalyst stabilizes the Ni-B species on the catalyst surface and increases the activity and stability of the amorphous Ni-B catalyst. When the suitable Ni loading (the theoretical mass of Ni and the mass percentage of K2Ti6O13) was 30%, the conversion of nitrobenzene and the choice of aniline were carried out under the conditions of a reaction temperature of 100 ℃ and a hydrogen partial pressure of 2.0 MPa for 120 min Respectively, up to 99.5% and 98.0%, respectively, and the conversion and selectivity of the catalyst were 98.0% and 93.0% respectively after being recycled 6 times.