Gospodarka Surowcami Mineralnymi - Mineral Resources Management

Abstract

the high temperature ashes (Hta) from bituminous coal combustion as a potential resource of rare earth elements introduction rees in coal constitute a group of elements of special importance. due to their chemical properties they are usually studied as one group rather than individually.rare earth elements (ree) include 17 elements, i.e.: 15 lanthanides (La, ce, Pr, nd, Pm, sm, eu, gd, tb, dy, Ho, er, tm, yb, Lu) and sc, y. there are several classifications of these elements that take into account geochemical and economic considerations (seredin 2010; seredin and dai 2012). according to a geochemical classification, ree fall into three subgroups: light rare earth elements (Lree: La, ce, Pr, nd, Pm, sm), medium rare earth elements (mree: eu, gd, tb, dy) and heavy rare earth elements (Hree: Ho, er, tm, yb and Lu). if yttrium is included in the lanthanides, the following three subgroups are formed: light elements (Lrey: La, ce, Pr, nd, sm), medium elements (mrey: eu, gd, tb, dy, y) and heavy elements (Hrey: Ho, er, tm, yb, Lu). the above classification is very convenient for describing the distribution of rare earth elements specifically lanthanides and yttrium (rey) in coal as well as in coal ash and in ores.