材料期刊网

为了探索新型聚合物双键加氢催化材料,采用XRD和自制吸氢装置等对贮氢合金MlNi_(5-x)(CoMnAl)_x 的组成、吸放氢性能及其催化加氢活性等进行了研究.MlNi_(5-x)(CoMnAl)_x 的P-C-T曲线表明,合金具有较低的平台压力,稳定性好;对比合金表面处理前后的吸氢动力学曲线发现:MlNi_(5-x)(CoMnAl)_x 吸氢初期速度较快,后期则随时间延长吸氢量缓慢增加,而经过[6M KOH+1%KBH_4]处理或Pd修饰后则可迅速达到吸氢平衡.催化聚合物双键加氢性能研究表明,未处理合金对NBR溶液加氢氢化度为零,经过[6M KOH+1%KBH_4]处理和钯修饰后的合金可对NBR、SBS、NR等聚合物双键加氢,氢化度分别为33.5%、32.3%、31.1%.说明合金表面组成及结构对其吸放氢性能和催化活性均有明显影响.

To explore a new catalyst for hydrogenation of carbon-carbon double bonds in polymers, the compo-sition of MlNi_(5-x)(CoMnAl)_x alloy, the hydriding-dehydriding characters of MlNi_(5-x)(CoMnAl)_x and MlNi_(5-x)(CoMnAl)_x > alloy pretreated by different methods as well as their catalytic activities were studied by XRD and self-made device. The P- C -T curve of MlNi_(5-x)(CoMnAl)_x shows that the hydrogen storage alloy has lower equilibrium pressure and good stability. Contrasting hydrogen absorption curve of MINi_(5-x)(CoMnAl) with that of MlNi_(5-x)(CoMnAl)_x pretreated with [6M KOH + 1% KBH_4]solution and deposited Pd, it is con-cluded that MlNi_(5-x)(CoMnAl)_x has a higher hydrogen absorption rate at first, and at the subsequent period, the amount of hydrogen absorption is tardily increased with time, and the equilibrium of hydrogen absorption-desorption is reached rapidly while MlNi_(5-x)(CoMnAl)_x is pretreated with [6M KOH + 1% KBH_4]solution and deposited Pd. The catalytic activities of above alloys for hydrogenation of double bonds in polymers such as NBR, SBS and NR were studied. Results show that there is no hydrogenation of NBR catalyzed by MlNi_(5-x)(CoMnAl)_x without any surface treatment. Using hydrides pretreated with [6M KOH + 1% KBH_4]so-lution and deposited Pd as hydrogenation catalysts, the double bonds in polymer such as NBR , SBS and NR can be hydrogenated, and the hydrogenation amounts are 33. 5 % , 2. 3 % and 1. 1% respectively. It is suggested that hydriding-dehydriding properties and catalytic properties are influenced by surface composition and structure of MlNi_(5-x)(CoMnAl)_x .