Sporinite

The reactive role of liptinite macerals in liquefaction has been partially documented (50,68). However, recent work has shown that unaltered sporinite often is encountered in the residues from both batch and continuous liquefaction runs. For example, sporinite was a common component in the residues of a high volatile A bituminous coal after hydrogen-transfer runs at 400° for 30 minutes (70). In spite of the relative unreactivity of the sporinite in this instance, the vitrinite clearly had reacted extensively because vitroplast was the predominant residue component. The dissolution rate of sporinite from some coals, even at 400°C, may be somewhat less than that of vitrinite. 

In contrast to sporinite, resinite from a Utah high volatile A bituminous coal reacted rapidly and more completely than the corresponding vitrinite. Table V shows the conversion levels achieved for a concentrate containing 75% resinite (mineral-free basis) reacted under relatively mild conditions. The results are curious. A fairly respectable level of conversion is achieved in 15 minutes at 350°C (under which conditions the associated vitrinite would presumably show little conversion), but longer times and a temperature of 370° have little further effect even raising the temperature to 400° does not show a major increase in conversion. 

Successfully applying the method used by Fenton to prepare his concentrates depends upon two factors. First, there must be adequate density differences between the macerals in the sample, and second, there must be an initially high concentration of the required maceral. In attempting to separate either resinite or cutinite from sporinite of the same coal, neither of these conditions can be fulfilled, at least when the coal is of bituminous rank or higher. If, however, samples on a semi microscale are acceptable, it is possible to prepare concentrates of resinites of satisfactory purity from bituminous coals by simple mechanical means. The method has been described by Murchison and Jones (17) and mainly involves picking with fine probes on differently prepared surfaces of coal under a stereoscopic microscope. Resinites from lignites pose less of a problem because their occurrence in fairly substantial lumps is quite common these and fossil resins such as kauri gum and amber usually can be prepared to a purity of almost 100% with ease. 

As in sporinites the very intense and broad band with peaks at 2860 and 2912 cm."1 testifies to the presence of large numbers of CH2 groups in resinites. Both macerals show a strong C-H deformation vibration at 1450 cm."1, but this is accompanied in the resinites by an absorption of weak to medium intensity at 1370 cm."1 that is absent or very weak in the sporinite spectra. 

Little comment can be made about the hydrogen-bonded OH groups that absorb close to 3300 cm."1. It is unlikely, however, within the rank range of resinites covered here that much variation in the intensity of this absorption would be recorded. The broad region of absorption between 1100 and 1300 cm."1 common to vitrinite and sporinite spectra is also found in the resinite spectra. The peak at 1270 cm. 1 almost certainly corresponds to the 1250 cm."1 band assigned by other workers to hydrogen-bonded phenolic structures. Fol-... 

Aliphatic structures are still of major importance in the second group of resinites, those of the bituminous coals, but aromatic structures are present in significant amounts. The spectra of these resinites display the type of absorption pattern that has come to be associated with other coal macerals, particularly the sporinites and to a large extent the vitrinites. This pattern is established in the resinites of the high volatile bituminous coals. Furthermore, resinites of this group are reactive during carbonization and oxidation processes in which their behavior parallels that of similarly affected vitrinites of equivalent rank. 

Materials. Analyses. The coal analyses are given in Table II both black durain and cannel coals are rich in sporinite material while the remainder are highly vitrainous. Two experiments were also carried out with material other than coal one with Neospectra carbon black and the other with a soot residue formed by the reaction of coal (CRC 802) in the plasma. The analysis (% daf basis) of the Neospectra carbon black was as follows C, 92.0 H, 0.8 N, 0.05 O by difference, 7.2 volatile matter, 9.2. All the materials were vacuum dried at 110°C. for several hours prior to use. 

Cannel coal Nonbanded coal in which the liptinite is predominantly sporinite. Fusain coal layers composed of chips and other fragments in which the original form of plant tissue structure is preserved commonly has fibrous texture with a very dull luster friable and resembles charcoal commonly concentrated in bedding layers or lenses that form planes of weakness in coal and thus is often exposed on bedding surfaces of broken coal. 

Sporinite maceral derived from the waxy coatings (exines) of spores and pollen. 

A. Large particle of pseudovitrinite at right showing serrated edges and well-developed cell texture. Particle at left is normal vitrinite with inclusions of sporinite (dark gray) and inertinite (white). 

Reflectance (in oil at 546 nm) Vitrinite Pseudovitrinite Fluorinite Resinite Sporinite Cutinite Amorphous Liptinite Semi-fusinite Fusinite Micrinite... 

Figure 5. Average fluorescence spectrum for sporinite in the Herrin (No. 6) coal seam. The reflectance of the seams is 0.65%.

Ottenjann, K., Teichmuller, M., and Wolf, M., Spectral fluorescence measurements in sporinites in reflected light and their applicability for coalification studies, in "Petrographic Organique et Potentiel Petrolier" Alpern, B., Ed. CNRS Paris, 1974c, pp. 379-407. 

Our recent development of a new procedure for the density separation of macerals offers a method for obtaining high resolution separation of the three maceral groups exinite, vitrinite, and inertinite, and can further resolve individual maceral types within these macerals groups, e.g., sporinite from alginite in the exinite group (1,2). The procedure... 

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