FEATURES OF X-RAY-DIFFRACTION MEASUREMENT OF THE CRYSTALLINITY OF DISPERSED PETROLEUM SYSTEMS

The active use of X-ray diffraction for investigating carbon materials began in the 1950s. A comprehesive review of early diffraction studie s of amorphous blacks and coals was carried out by Ergun and Tiensuu [ 1], and for petroleum systems by Erdman and Wender [2]. Warren was the first to develop and correct the shape, position and intensity of ban ds with the dimensions of layers [3]. Labout showed that petroleum asp haltenes give the powder diffraction pattern characteristic of amorpho us substances [4]. Nellensieyn was the first to observe the band corre sponding to an interplanar distance of 0.35 nm and the similarity of t his characteristic for petroleum asphaltenes and amorphous blacks [5].