| 摘要 |
The invention relates to a novel structural form of expanded graphite which possesses a relatively high bulk density is disclosed. This expanded graphite is obtained by treating a natural graphite with a mixture of nitric acid and sulfuric acid, washing the treated graphite by an aqueous solution containing magnesium ions, followed by a thermal treatment at a temperature of above 1200 DEG C. A preferred aqueous solution to be used in said washing will contain magnesium sulfate, the resulted product having a pH in the range of 6.5 to 6.9. A preferred thermal treatment is in a flame resulted from a mixture of butane and oxygen. In this manner, the expanded graphite will be produced in-situ near the envisaged area for its use, being spread thereon by the combustion gases. The novel structural form of expanded graphite has the property to absorb relatively large amounts of liquid materials, such as petroleum products and strong mineral acids. |
