Lignite extract

Conditions 850F, llOO psig, 300 H2 GHSV, 20 wt lignite extract in toluene, Nalco Ni-Mo catalyst. 

Run 15 was carried out with a higher LHSV of 1.6, and the results are not too much different from Runs 13 and lit. The heteroatom removals are about the same. The heavy oil fraction, however, was increased to 13 from 30 and 36% (Runs 13 and lit). Thus, the conclusion is that the lignite extract, a solid, can also be upgraded to yield a syncrude by the supercritical hydrotreatment process. 

The proton NMR spectrum of the Me2S0 extract of the lignite was obtained using a XL-200 Fourier transform proton NMR spectrometer. Details of lignite extraction with Me2S0 are described elsewhere (, 5). Instrumental conditions for the measurement of the spectrum were as follows frequency - 200 MHz proton sample state - liquid solution solvent - Me2S0-dg locked sample concentration - ca. 200 mg/10 ml probe temperature - 25 C sweep width - 2600.1 Hz acquisition time - 1 second internal reference - tetramethyl silane number of transients - 1500 pulse width - 5.0 piseconds. 

Between 1870 and 1913 Germany s bituminous coal output increased more than sevenfold and its lignite extraction grew more than elevenfold its steel production was nearly 140 times larger in 1913 than in 1870, and at 17.6 Mt it greatly surpassed the combined British and French total of 12.5 Mt. Its net national product (expressed in constant prices) grew 3.1 times in forty-three years see Mitchell, B. R. 1981. European Historical Statistics. New York Facts on File, pp. 383, 420-422, 817-821. 

Pyrolysis ofVegetals. Many pubhcations concern the synthesis of dihydroxybenzenes by wood, lignites, and tree bark pyrolysis (61). The selective extraction of these compounds in low concentration from the cmde mixture remains a significant problem. So far, the price of the extraction overcomes the advantage of starting from a cheap starting material. 

Humic acids are alkaH-extractable materials and total humic acid content is a term that refers to the humic acid content of coal that has had its carboxylate cations removed with sodium pyrophosphate. Values for some typical AustraHan brown coals range from 24—92% (13). Treatment of lignitic coals with mineral acid to release the alkaH and alkaline cations may dissolve up to 20% of the coal. The naturally moist coals are slightly acidic and have a pH of 3.5—6.5. 

Monta.n Wax. An important product of the direct extractive treatment of lignitic coals is montan wax [8002-53-7]. The term montan wax or Bergwachs refers strictiy to the material obtained by solvent extraction of suitable German brown coals. The generic term for similar materials is montana wax. The small quantities made outside Germany are usually referred to as montan, prefixed by the country of origin (see Waxes). 

Montan Wax. Montan wax [8002-53-7] is derived by solvent extraction of lignite (qv). The earliest production on a commercial scale was in Germany during the latter half of the nineteenth century, and Germany continues to supply the majority of the world s production of montan wax. Montan wax production at Amsdorf is part of a massive coal-mining operation from a continuous vein and raw material is expected to last for decades. Montan wax is also produced in the United States. Imports of montan wax into the United States for the years 1990—1995 are Hsted in Table 1. Germany suppHes over 80% of the montan wax imported into the United States (3). 

FIGURE 15.7 Secondary changes in the total group composition of soluble organic matter as a result of simulated water washing extracts of the Miocene lignite and shale (both of the Bechatow open cast mine, Poland), the Upper Devonian shale (the Holy Cross Mountains, Poland), and the Upper Carboniferous bituminous coal (the Upper Silesia Coal Basin, Poland). 

Montan wax is obtained by solvent extraction of certain types of lignite or brown coal. It has a dark colour when not treated, but it is lighter when refined. Its chemical composition includes esters of C22 C32 acids (53%), free acids (17%), free alcohols (1 2%), ketones (3 6%) and terpenoids (20 23%) [85]. 

Besides the conventional uranium resources, there are also the so-called unconventional uranium resources , which are defined as deposits with very low uranium content, from which uranium is typically only recoverable as a minor by-product. These unconventional uranium resources are obtained from the extraction of phosphates, non-ferrous ores and carbonatites, as well as black schist and lignite. It has to be noted that the distinction between conventional and unconventional resources is not entirely clear cut, but is, instead, somewhat transitional. 

The dewatering pressure is one of the major factors determining the extraction of water, and several good water samples were obtained from the Bowmans, Lochiel and Sedan lignite samples. A suitable sample of mechanically removed water could not be obtained from the Kingston sample. 

Seven Argonne Premium coal samples ranging from lignite to low volatile bituminous in rank were analyzed by Pyrolysis-Field Ionization Mass Spectrometry (Py-FIMS) in order to determine the existence and structural nature of a thermally extractable "mobile phase". In addition, Curie-point Pyrolysis-Low Voltage Mass Spectrometry (Py-LVMS) was employed to demonstrate the importance of mild oxidation on the thermally extractable mobile phase components. 

Py-FIMS results clearly reveal the existence of a thermally extractable, bitumen-like fraction which is chemically distinct from the remaining coal components. In lignite, several biomarker compounds were noticeable in the mobile phase components while bituminous coals contain various alkylsubstituted aromatic compounds in the mobile phase. Blind Canyon coal, which contains 11% resinite, exhibits mobile phase components believed to originate from terpenoid aromatization. Curie-point Py-LVMS results illustrate the importance of the oxidation status of coal for studying the mobile phase since mild air oxidation severely changes the structural characteristics of the thermally extractable mobile phase. 

In most experiments the sulfur removed from the Mequinenza lignite appeared in two products, hydrogen sulfide and liquid organosulfur compounds (LOG) present in the THF-soluble extract There are three mechanisms by which these two sulfur-containing products could be produced from the lignite ... 

Montan wax is considered as a semimineral, intermediate between the vegetable and mineral waxes. It is extracted from brown coal or lignite. Chemically it consists of esters of wax acids,... 

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