Expansible graphite with low thermal weight loss and high purity and preparation method thereof

The invention relates to expansible graphite with low thermal weight loss and high purity. A preparation method of the expansible graphite with low thermal weight loss and high purity comprises the following steps of: placing expansible graphite in a drying tank to uniformly heat every grain of graphite; uniformly spraying a sodium phosphate solution according to the ratio of 0.4-1.2% of the massof graphite when the moisture of the expansible graphite is reduced to 0.5-1%, and continuing to stir after the sodium phosphate solution spreads over the graphite grains; uniformly spraying a sodiummolybdate solution according to the ratio of 0.2-0.6% of the mass of graphite, and uniformly stirring; and storing the expansible graphite to obtain the expansible graphite with low thermal weight loss and high purity. The thermal weight loss of the graphite obtained by the invention is detected to be 1-8% under the condition of 670 DEG C, and the service life of the product is long. The graphitehas the high temperature re