| 制备NdNi5的还原扩散过程 |
| REDUCTION-DIFFUSION PROCESS IN PREPARATION OF NdNi5 |
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| 摘要: 将CaH2、Nd2O3和Ni粉混匀,并在氢气氛下加热到1000℃恒温4小时后,产物经洗涤,真空干燥得到NdNi5。本文在确定NdNi5制备条件的同时,对还原扩散过程进行探讨。实验结果表明在制备NdNi5的还原扩散过程中起还原Nd2O3作用的除CaH2以外还有金属Ca。反应扩散不只是在Nd和Ni之间进行,在1000℃扩散初期Ca亦参与这种扩散。形成中间产物Nd1-xCaxNi5。随着时间的增加Ca逐渐被Nd所取代,最后得到NdNi5。 |
| 关键词: 还愿扩散法 扩散反应 取代反应 配位滴淀 NdNi5的制备 |
| 基金项目: |
Abstract: NdNi5 is prepared by the means of reduction-diffusion. The sample were prapared first by blending well Ni, Nd2O3 and CaH2 powder and then heat at 1000℃ in hydrogen and time for maintaning a constant temperature is 4hr. The sample was washed with a lot of water first and then with dilute acetic acid. After filteration and suck dry, the sample was dried in vacuum at blow 50℃.The phase of sample (H5,K2) is only NdNi5 with X-ray diffraction analysis. The atomic rate of Nd to Ni is 1:5 as shown by the complexome-tric titration. The Ca content is 0.3wt% in the sample(H5,K2) with atomic absorption spectrometry. There are two mainly reaction in reduction-diffusion process in the literature. The reaction equation were as follows:  In this paper we determine experimental condition and study reduction-diffusion process for preparation NdNis5 Experimental, results show that not only CaH2 but calcium may be to reduce Nd2O3 in the preparation NdNis with reduction-diffusion process. It's reaction equation was as follows: 3Ca + Nd2O3→2Nd + 3CaO As a whole not only Nd and Ni diffused each other, at first so did calcium. There are two diffusion reactions and one substitution reaction in reduction-diffusion process. Nd + 5Ni→NdNi5 Ca + 5Ni→ CaNi CaNi5 + Nd → NdNi5 + Ca Replaced calcium by neodymium gradually as the time increased. Finally NdNi5 was obtained in hydrogen. |
| Keywords: reduction-diffusion means diffusion reaction substitution reaction complexo-metric titration preparation of NdNi5 |
| 投稿时间：1985-09-11 |
| 摘要点击次数: 1409 |
| 全文下载次数: 1686 |
| 顾菡珍,吴艳钟.制备NdNi5的还原扩散过程[J].无机化学学报,1986,2(3):73-78. |
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