CATALYST ON GRA PHITIZATION OF CARBON (I)

Abstract

We planned to lower the graphitization temperature by relying on the action of catalyst.Our observation on aluminosilicate minerals is based on the fact that the graphitelike lustre of the smonked tile produced with the body, the surface of which is smeared with the clay containing micaceous minerals such as sericite, is better than that of one produced without such a clay.In case of sericite, the following were obtained.Its own action increased suddenly at about 1800°C and disappeared already at 2000°C, the temperature at which the graphitization of the simple coke not containing sericite increased suddenly, but the effect obtained was equivalent to the heat-treatment of 2500°C without sericite. It was found that sericite is effective to the contraction of the interlayer spacing, d, and to the growth of the average diameter of an hexagonal network layer, La. In the range of from 2000° to 2400°C, the best result was observed by applying about 8% of sericite. Both the uncalcined sericite and the anhydrous one prepared by calcination showed no difference in the effects on the graphitization and on the physical properties of the produced graphite. The mixture of reagents of the same compositions as sericite was not effective. Sericite also exhibited the purifying action. Next the higher graphitized product was trial manufactured with sericite on a large scale by the industrial process in haste; thus it was confirmed that the industrial application of sericite is possible.Lepidolite of the same mica group as sericite, petalite, and kaolinite were effective, too.The following were concluded from the above facts.The catalytic action may be effective in the temperature range which is necessary to complete the final carbonization of the residual incomplete parts in the structure of coke which were not carbonized completely yet at the coking temperature. The hexagonal network layer structure of aluminosilicate may act effectively on the growth of the layer structure of graphite. The increase of graphitization and purification established during the graphitization process may connect closely each other.