Graphite natural

Natural Graphite, Graphite Powders, Particles, and Compounds 

Natural graphite is a relatively abundant mineral found in many parts of the world and known to man for centuries. It was originally considered a separate substance, thought to contain lead and often confused with molybdenum sulfide. In 1855, Brodie prepared pure graphite and unequivocally identified it as an allotrope of carbon. Today, although the majority of graphite products are synthetic, natural graphite is still preferred for some applications.i i 

The worldwide production of naturally occurring graphite increased from 392 10- t/a in 1970 to 596.7 10 t/a in 1980 and in the period 1980 to 1993 remained almost constant at an average of 597 10- t/a. Since 1980 China has been the leading producer, accounting for 25% of worldwide production and 25% of the economically 

Natural graphite is interesting for special applications, due to its high crystallinity. Demand, particularly for high grade types, has therefore increased. Synthetic graphite is, however, predominantly used in the processing industry. 

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Natural gas pipeline Natural gas wells Natural graphite Natural Graphite Natural gums... 

See Carbon, CARBON AND ARTIFICIAL GRAPHITE Carbon, NATURAL GRAPHITE. 

SoHd lubricants ate added to help control high friction characteristics in high speed or heavy-duty appHcations where high temperatures are generated. Molybdenum disulfide [1317-33-5] M0S2, may be used alone or in a complex compound formed by grinding with fine natural graphite, and zinc sulfide [1314-98-3] ZnS. Other compounds include calcium fluoride, cryoHte [15096-52-3] Na AlF, rare-earth oxides, and metal sulfides, eg, iron, antimony, or zinc (see LUBRICATION AND LUBRICANTS). 

AH graphite has crystal stmcture but only certain kinds and sizes of natural graphites are commercially classified as crystalline, a term used for import duty purposes. Throughout this article reference is made separately to dake, vein (lump or high crystalline), and amorphous forms, all of which are essentially the same crystalline form of carbon. However, fine stmctured graphites (cryptocrystalline (2)) have been classified as amorphous. 

Eig. 1. Laue x-ray diffraction pattern of a single natural graphite crystal. 

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