铝电解槽炭阴极石墨化影响因素

来源期刊：中国有色金属学报1998年第3期

论文作者：姚广春 张晓明 司仑 纪周礼 孟庆利

文章页码：515 - 518

关键词：炭阴极； 石墨化度； 催化

Key words：carbon cathode ； graphitization ； catalytic

摘    要：普通无烟煤基阴极炭块在铝电解槽中使用4个月左右就石墨化。 为了研究此石墨化机理，利用20 kW工频炭管炉进行了包括在炭素试样中添加NaF，Na₃AlF₆,Na₂CO₃等并在炭素试样上通入直流电的试验。 试验温度为1400～1800 ℃，提高温度的目的是为了加速炭素试样的石墨化过程； 在高温下，Na₂CO₃能够与碳发生反应生成金属钠蒸气。 试验结果表明， 这些因素都能使炭素试样的石墨化度增大，都具有一定的催化作用。 铝电解槽炭阴极的石墨化可能是由于氟盐、金属钠和直流电场综合作用的结果。

Abstract: The general anthracite carbon cathode used in alumina reduction cell after about 4 months can become graphitization. It is an interesting graphitization phenomenon at low temperature. In order to study the graphitization mechanism，some experiments were carried out in a 20 kW carbon tube furnace.The experiments involved adding additives NaF, Na₃AlF₆, Na₂CO₃ to carbon samples，setting up direct current on carbon samples. The experiment temperature was in range of 1 400～1 800 ℃. To raise the experiment temperature is to accelerate the graphitization of carbon samples. Na₂CO₃ can react with carbon to produce metallic sodium vapor at high temperature. It was found that all these factors can enhance the graphitization centigrade of carbon samples, and they all have some catalytic action on the carbon graphitization. The experiment results showed that the carbon cathode graphitization in alumina reduction cells may be due to the synthetical actions of floride, sodium and direct current.