Abstract
Transformations of high-molecular-weight compounds of bituminous sands natural bitumen under the heat treatment are studied.Cracking and extraction of Kazakhstan's bituminous sand bitumen were carried out.Thermal processing of natural bitumen leads to a general change in the chemical composition of components and an increase in the output of certain factions.Molecular structures of the tar and asphaltene components of natural bitumen are built from the data of elemental analysis, 1HNMR spectroscopy and molecular weight.The content of oil, tar and asphaltenes were determined and the elemental composition of tar-asphaltene compounds was evaluated.The high molecular compounds were presented as giant molecules containing small aromatic islands with some linked by aliphatic chains.