Study on Influence of Processes on the Dehydrogenation Performance of NaAlH4

摘要:

分析了制备工艺过程、球磨设备、试样放置时间以及球磨时间对NaAlH4放氢性能的影响。其中除了试样3是采用高能球磨机外，其它所有试样均采用行星式球磨机。结果表明，这些因素对NaAlH4放氢性能的影响非常明显。试样在球磨过程中经过上下翻转后，其放氢量明显比不翻转高出了50%(质量分数)。不同球磨设备研究结果显示，试样3经过高能振动球磨机球磨后，其放氢量比行星式球磨机制备的试样的放氢量明显提高了。试样放置时间与试样球磨时间的研究结果显示，制备好的球磨试样经过24 h放置后，其放氢量明显提高。此外，试样经过不同时间球磨后，其放氢量也有明显的不同。经研究发现，球磨80 min试样的放氢量比球磨100 min和球磨40和60 min试样的放氢量要高，但和其它的影响因素相比，球磨时间对NaAlH4放氢性能的影响相对较小

Abstract:

In this paper, the effects of preparation process, ball-milling equipments, storing time and ball-milling time on the dehydrogenation performances were analyzed. All the samples were ball-milled by planetary ball mill except for sample 3 which was ball-milled by high-energy vibration ball mill. The results indicate that the above mentioned influence factors present obvious effect on the dehydrogenation performances of NaAlH4. The dehydrogenation amount of the samples turned up and down during ball milling increases by 50wt%. Compared to the samples prepared by planetary mill, the dehydrogenation amount of samples prepared by the high-energy vibration ball mill increases markedly. The results from studying on storing time and milling time show that the dehydrogenation amounts of the samples milled by planetary mill and laid aside for 24 h get an obvious increase. In addition, the amount of the hydrogen release of the samples milled for different time with planetary mill presents significantly difference. The amount of the hydrogen release of the sample milled for 80 min is higher than those milled for 100, 40 and 60 min. However, compared to other influence factors, the effect of ball-milling time on NaAlH4 is smaller