Rare earth element geochemistry of coals from the Mazino Coal Mine, Tabas Coalfield, Iran

Abstract

The Mazino deposit with 650 Mt estimated reserves is the largest steam coal deposit in Iran. The concentrations and distribution patterns of rare earth elements (REEs) in coal, coaly shale and siltstone samples from the Mazino mine were studied by inductively coupled plasma mass spectrometry (ICP-MS). The concentrations of ∑REEs in coal samples range from 16.4 to 184 ppm with average of 88.9 ppm. There are two types of distribution patterns of ∑REEs in the coal samples. One type, in the part of the section has slightly higher ∑REE concentrations and (Light REEs)/(Heavy REEs) ratio with a flat normalized REEs pattern; the other is enriched in HREEs relative to LREEs. The positive correlation and vertical variations of ∑REEs mainly follow those of the coal ash yield, and the SiO 2 , Al 2 O 3 , and K 2 O percentage in the coal, suggesting that the ∑REEs concentrations in coal are mainly controlled by input of land-derived detritus. There is an overall increasing trend in ∑REEs content upward through the coal seam.

Environmental Technologies to Treat Rare Earth Element Pollution: Principles and Engineering

“…The REE content of coal ash is close to the REE content of the ion-adsorbed clays that are currently mined in China. For example, in coal samples from the Mazino Coal Mine (Tabas Coalfield, Iran), ΣREE range from 16.4 to 184 µg/g with an average of 88.9 µg/g (Pazand, 2015). On the other hand, the ΣREE value is ∼ 404 µg/g in the world coal ash (Dai et al, 2016).…”

Organic petrology and geochemistry of Triassic and Jurassic coals of the Tabas Basin, Northeastern/Central Iran

“…Although the mineralogy, inorganic geochemistry, and stratigraphy of the Mesozoic coals of Iran have been investigated by several authors (e.g. Pazand 2015;Goodarzi et al 2006;Ghassabiyan et al 2010; Moore and Esmaeili 2012;Ardebili et al 2012;Moosavirad et al 2013;Ghavidel-Syooki et al 2015;Rajabzadeh et al 2016), only little information is available on the characteristics of organic material that formed these coals (Solaymani and Taghipour 2012;Stasiuk et al 2006;Alizadeh et al 2011Alizadeh et al , 2015Ghavidel-Syooki et al 2015). In order to investigate depositional conditions, plant input and thermal maturity of the aforementioned Iranian coal deposits, a wide range of organic petrological and organic geochemical methods was applied.…”