Glow discharge excited low temperature ashing

Genesis of some tertiary Indian coals from the chemical composition of ash – a statistical approach: Part 1

“…The chemical composition of coal ash varies widely depending upon the inorganic and organic constituents of coal and their association with each other. Various authors (Thiessen 1945;Francis 1961;Dixon et al 1964;Machowsky 1968;Shibaoka 1972;Stach et al 1975;Jenkins and Walker 1978;Yudovich 1978;Berkowitz 1979;Adolphi and Storr 1985;Van der Flier-Keller and Fyfe 1988;Vassilev et al 1997) have grouped the ash and inorganic constituents of coals into different classes as inherent adventitious (extraneous) and free dirt syngenetic and epigenetic primary, secondary, and tertiary, detrital and authigenic or biogenic (plant), sorption, concretion (diagenetic), chemigenetic, clastic (detrital) and infiltration (epigenetic). The source rock types, nature of the coal forming environment, conditions of burial and degree of coalification can be interpreted to infer the genesis of coal (Van der Flier-Keller and Fyfe 1988).…”

First Application of 27Al Multiple Quantum Magic-Angle Spinning Nuclear Magnetic Resonance at 16.4 T to Inorganic Matter in Natural Coals

“…Detailed studies on the inorganic matter in coals are very important, from the viewpoint of both geology (coalification and diagenesis) and coal utilization. − X-ray diffractometry (XRD) is a common and powerful tool in the analysis of inorganic matter in coals. Several characterizations of clay minerals and aluminosilicates in natural coals, , low-temperature ashing residues, − and combustion coals have been performed using XRD. However, it is often difficult to assign inorganic matter through the use of XRD when samples are noncrystalline, as are several clay minerals that give the poorly resolved patterns.…”

Mineral Matter Characterization in Olive Stones by Joint Use of LTA, XRD, FT-IR and SEM-EDX

“…Although LTA has been repeatedly proposed as the procedure that causes the least alteration in the initial state of the minerals present in coal, some sources of error are known to occur with this m ethod. 13,14,[18][19][20] These sources include loss of hydration water in gypsum, partial oxidation of pyrite to sulfates (nevertheless, sul des are unlikely to be present in vegetable feedstocks), and organic sulfur and nitrogen xation by interaction with ion-exchanged alkali and alkaline-earth elements. Other alternative m ethods of concentrating m ineral matter from coal have fewer chances of success than LTA when applied to biomass.…”

“…This procedure allows the inorganic fraction to be isolated with minimal alteration of its original form . [11][12][13][14] With the use of the mineral concentrate produced in this way, identi cation of inorganic species is accomplished by combining X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The study is completed with an examination of the morphological features of the LTA sample by m eans of scanning electron m icroscopy (SEM) coupled with local energy-dispersive X-ray microanalysis (EDX), which provides data on the distribution of inorganic elements.…”