CHEMICAL CLEANING OF ULTRADISPERSED DIAMONDS WITH HYDROGEN-PEROXIDE

Ultradispersed diamonds (UDs) are made by the detonation of certain explosives and can be purified from nondiamond carbon by the use of aqueous hydrogen peroxide with added bases, salts, or acids. The UD is most effectively purified in the presence of small amounts of nitric acid. Studies have been made on the extent of UD purification in relation to treatment time, HNO3 concentration, and H2O2 consumption. Measurements have been made on the rate constants for the oxidation of nondiamond carbon at 150-260 degrees; the apparent activation energy is E approximate to 2.6-2.9 kJ/mole.