Occurrence, properties, and uses of some natural bitumens

reportIn this report, the Federal Bureau of Mines presents a summary of the occurrence, properties, and uses of some natural bitumens, using the layman's or dictionary definition of bitumens - that is, naturally occurring hydrocarbons. Emphasis is on the less common solid and semisolid bitumens, particularly those occurring or used to some extent in the United States. This comprises data from many sources and references to these sources for more detail than is given in this summary. This paper was prepared primarily to answer questions about some of the less known bituminous materials. The word hydrocarbons could just as well have been substituted in the title for bitumens, but bitumens was used, since an abstract of the paper was presented at a meeting where the major emphasis was on bituminous materials. The reader will realize that coals, of which only the more unusual such as the cannel coals and torbanites are discussed in this paper, are primarily mixtures of bituminous materials and carbon. The amount of bituminous material, or volatile matter, in coals is greatest in the lower rank coals and the unusual types described in this paper, and decreases as coal rank increases. However, since no method other than destruction of the original coal substance by heat is known that will separate the volatile matter from the carbon, it appears reasonable to classify the coals with other bituminous materials, particularly since bituminous coal - the most widely used coal - by its name indicates the combination of bituminous materials and carbon. l/ Work on manuscript completed March 1960. 2/ Former Bureau of Mines chemical engineer, Branch of Bituminous Coal Research, Division of Bituminous Coal, Bureau of Mines, Washington, D. C; now principal associate, Fuels Consulting and Testing Associates, McLean, Va. 3/ Former Bureau of Mines research assistant, Branch of Bituminous Coal Research, Division of Bituminous Coal, Bureau of Mines, Washington, D. C; now a secretary, Office of the Assistant Secretary, Mineral Resources, Department of the Interior, Washington, D. C