制备了一系列Ni掺杂的Pd/CNT催化剂(Ni-Pd/CNT),通过XRD、BET、TEM、H₂-TPR、XPS等手段对其进行表征,并考察了其在聚苯乙烯(PS)加氢中的催化性能。结果表明,Ni的加入提高了Pd的分散度,起到了协同催化的作用,大幅度提高了Pd/CNT的催化活性和链长保留率。Ni-Pd/CNT催化剂的最佳制备条件为:5% Pd、5% Ni、400℃焙烧4 h、350℃碳化2 h;Ni-Pd/CNT催化PS加氢的最佳反应条件为反应温度160℃、反应压力6 MPa、反应时间8 h、催化剂质量分数10%,此时,PS的转化率达98.6%,同时链长保留率达89.3%。Ni掺杂的Pd/CNT催化剂活性的提高缩短了反应时间,有效减少了分子链的断裂,且催化剂具有良好的稳定性。

A series of Ni-doped Pd/CNT catalysts (Ni-Pd/CNT) are prepared,and characterized by means of XRD,BET,TEM,H₂-TPR and XPS.Their catalytic performances are evaluated through the hydrogenation of polystyrene.The results show that the addition of Ni improves the dispersion of Pd,plays a synergistic role in catalysis,and greatly improves the catalytic activity and chain length retention rate of Pd/CNT.The optimal preparation conditions for Ni-Pd/CNT catalyst are determined as follows:the contents of both Pd and Ni are 5%,the calcination has performed at 400℃ for 4 h,and the carbonization has performed at 350℃ for 2 h.The optimal reaction conditions for the hydrogenation of polystyrene over the prepared Ni-Pd/CNT catalyst are obtained as follows:the dosage of Ni-Pd/CNT catalyst is 10%,and the reaction has carried out at 160℃ and 6 MPa for 8 h.The conversion of polystyrene reaches 98.6%,and the chain length retention rate reaches 89.3% under the optimal reaction conditions.The promoting effect of Ni helps to shorten the reaction time,and effectively reduce the breakage of molecular chains.Ni-Pd/CNT catalyst also shows a good stability.

刘振宇(1987-),男,博士,高级工程师,研究方向为有机化工,liuzheny.mmsh@sinopec.com