Room temp. reduction of metal oxides by mechanical alloying

用机械合金化法研究了金属氧化物在室温下的还原。用固体还原剂对固体金属氧化物粉末进行球磨，在力的作用下引起非平衡化学反应。实施了4项制度；(1)氧化银（Ag_2O,Ag_2O_2），(2)氧化铜（Cu_2O,CuO），(3)氧化锌（ZnO）和(4)氧化铁（FeO,Fe_3O_4, Fe_2O_3）。用碳粉作还原剂。(1)和(2)实验均取得了成功，产业化的可能性较大。并预测了金属氧化物的预处理对反应的影响。反应器系统：实验采用Spex 8000混合器。用氧化锆（体积为60cc）试验制备反应器。(1)（银）：初级和次级氧化物都在较短的时间内被还原成金属银，大约20或30分钟。这些反应都是瞬间的。(2)（铜）：在两种氧化物中分别作用100或200小时，得到金属铜粉。这些反应一直不活跃。(3)（锌）：由于氧化锌原料极易吸附h2o，因此需要进行焙烧预处理。过量的碳使反应无活性地进行。(4)（铁）：实现了赤铁矿（Fe_2O_3）还原为磁铁矿（Fe_3O_4），但后续反应中断。分析认为，粉末与反应器的黏附引起的中断使投入的机械能松弛。

We examined the reduction of metal oxides at room temperature by mechanical alloying method. Through ball-milling the solid metal oxide powders with solid reductant, the non-equilibrium chemical reactions are induced by force. 4 systems were carried out ; (1) silver oxides (Ag_2O,Ag_2O_2), (2) cupper oxides (Cu_2O,CuO), (3)zinc oxide (ZnO) and (4) iron oxides (FeO,Fe_3O_4, Fe_2O_3). Carbon powders were used for reductant. (1) and (2) were successful, so there is good possibility of the industrialization. And It was predicted that the pretreatment of the metal oxides was important for the reactions.Reactor System : Spex 8000 mixer was used for the experiments. The reactor were produced by way of trial with zirconia (volume = 60cc).Exp.(1) (Silver) : Both of the primary and the secondary oxides were reduced to metallic silver for comparatively short period, 20 or 30 minutes. Those reactions were momentary.Exp.(2) (Copper) : Metallic copper powder were obtained after 100 or 200 hours in the both oxides. Those reactions were continuously inactive.Exp.(3) (Zinc) : The raw ZnO easily adsorps H_2O,therefore the pretreatment, roasting, is necessary. With excess carbon, the reaction advanced inactively.Exp.(4) (Iron) : The reduction from hematite (Fe_2O_3) to magnetite (Fe_3O_4) were achieved, however the following reactions were interrupted. It is suggested that the interruption caused from that the adhesion of the powders to the reactor relaxd the invested mechanical energy.