Preparation of fullerenes from several Chinese coals

We report that fullerenes and a number of carbon nanomaterials can be prepared from a suit of Chinese hard coals by a D.C, are method. The fullerene yields are directly related to the coal properties and range from 1.28% to 2.38%. It is found that the fullerene yield increases as the carbon content in coal increases and as ash content in coal decreases. After removal of ca.50-80% mineral matter in raw coals, the fullerene yields increase by ca.80-226%. The highest fullerene yield is 6.51% which compares favourably with the yield of 6.89% obtained from high purity graphite under the identical conditions. An interesting linear relationship between the molar C-60/C-70 ratio and the volatile matter content in coals is also noted.