Research On The Purification And Classification Techniques For Ultra-fine Diamond Micropowder

This paper tells the technology of the diamond purification and classification. At present, the low quality diamond purified by the traditional methods domestic, its purity only could attain to 97%. Aiming at the actuality that a huge gap is existing between the ultrfme diamond demestic and international technical standard, a classification technology about the ultrfme diamond was researched, in which the two key technologies of particle size and dispersion of distribution both are measured up by international advanced standard. It is processed with the purification togather. The raw materials is dissolved ( melted ) by acid mixture, then washed by centrifugal effect. Put into the calculated surfactant, and the diamond granularity is observed under the microscope.Though the amount experiments, we have designed one new purification method. In the strong acid, the congeries of the diamond in the crystal process could be separated by ultrasonic to add the interface of solvent and the decompose effect of impurity was enhanced to 99.97% finally. The purification results could be contrasted and analyzed by modern test equipments, e.g. TG-DSC, XRD, Laser-Raman Spectrum. There are the discussion about the most advanced standard of ultrafine diamond classification in the paper, and report about the commonly used national technology of ultrfme diamond classification and the newest international technical equipment and the assistant equipment of classification. The dispersion experiment was mainly studied about the dispersion condition and performance of ultrafine diamond in the water, and many experiments were made to check the impacts of the dispersion property of diamond under the conditions of different surfactants and their combinations, different solution concentrations, and different dispersion time and intensities of the ultrasonic. Moreover, the analysis of the dispersion behavior of the diamond powders in the water was made through studying the surface characters of ultrafine diamond and the dispersion mechanism of the surfactants.The diamond powders and an amount of reagent A were mixed by using ultrasonic, then, they are added to the sealed equipment of mid-temperature high-pressure, and control the temperature and time of reaction, under other conditions of reagent dosage, proportion, temperature, pressure and time. At last, the washed diamond purity was tested. The effect of the experiment parameter to the purification result is like that: the purity is increased with the increasing acid mixture amount within the reagent ratio 4, moreover, the amount is 4,the result is...