A method of making a polycrystalline diamond compact includes mixing a diamond particle feed with a binder to form a mixture, forming the mixture into a precompact, heating the pre-compact in a non-oxidizing atmosphere to substantially drive off the binder, oxidizing the pre-compact in an oxidizing atmosphere at a temperature and for a time sufficient to burn off non-diamond carbon without overoxidizing diamond, and sintering the pre-compact at high pressure and high temperature to form a polycrystalline diamond compact. The method may also include oxidizing the diamond particle feed prior to mixing with the binder.