真空下从铝土矿中直接提取铝的研究

Experimental Study of Vacuum Aluminum Extraction from Bauxite

利用低价铝氟化物歧化反应分解可以得到金属铝的特性,用焦炭作还原剂,在真空条件下,从铝土矿中提取铝进行了实验研究。实验得到:残余压力300Pa以下时可以得到金属铝,温度在1300～1550℃范围内都可以得到金属铝。氧化铝的还原率随反应温度的升高而升高,当温度达1400℃时还原率达80%以上,当温度达1450℃时还原率超过81%。冷凝温度在700～830℃区间,金属铝颗粒直径达3～4mm。此工艺也可以用于从低品位含氧化铝原料中直接提取金属铝。

A novel technique has been successfully developed to directly extract aluminum from bauxite in vacuum by means of the disproportionating reaction of sub-fluoride of aluminum, with coke as the reduction reagent. The impacts of the experimental conditions, including the heating and condensing temperatures, and residue pressure, on aluminum extraction were experimentally studied. The results show that at a residue pressure of 300Pa, metallic Al can be extracted at a temperature ranging from 1300 ~ 1550℃. As the heating temperature rises up, the reduction increases, reaching 80% at 1400℃and over 81% at 1450℃, respectively. And the A1 grain size was found to be about 3 - 4mm at a condensing temperature of 700 - 830℃.