Solvent Refined Lignite Research Articles

石炭液化用触媒に関する研究 ＳＲＬの水素化分解反応に対する各種触媒の接触作用の比較

The hydrogenolysis of Solvent-Refined Lignite (SRL) obtained from Morwell coal was conducted in the presence of four kinds of catalysts with tetra-lin or creosote oil as solvent at 693 K. The products were separated into five compo-nents and each of them was analyzed by 1H-NMR. With Adkins' catalyst, hydrogena-tion of aromatic nuclei predominates over cleaving linkages between the structural units. The catalysis of Fe2O3+ S is similar to that of Adkins' catalyst but the former is less active. MoO3-TiO2 is the most powerful catalyst for the hydrogenolysis of SRL among the catalysts employed here and it seems to contribute to cleaving linkages be-tween the structural units. The catalysis of MoS3-Al2O3 is similar to that of MoO3-TiO2 in the presence of solvent. Asphaltenes and Insolubles decrease with reaction time. However, after a certain composition of the products reaches, decom-position of naphthenic structures seems to occur accompanied by its dehydrogenation. It was concluded that the specific behavior of each catalyst for the hydrogenolysis of the SRL agrees with that for the reactions of the model compounds.

Gel permeation chromatographic analysis of solubilized lignite asphaltenes and preasphaltenes

GPC data have been measured for a series of acetylated solvent refined lignite (SRL) asphaltenes and preasphaltenes and model compounds. Two structural parameters, the degree of aromatic condensation ( H aru C ar ) and the molar hydrogen to carbon ratio ( H C ), were employed to correct the molecular weight of the samples for linear molecular size. For the model compounds, H aru C ar was more effective, whereas the SRL materials were better adjusted by H C . The calibration standards deemed most suitable for determination of molecular weight of SRL by GPC are the SRL samples themselves.

Extended Operation of a Solvent Refined Lignite Process Development Unit

Abstract Extended operation of the University of North Dakota's process development unit for production of solvent-refined lignite is reported. Gas and solvent recycles were successful during three 28-day runs. Solids accumulation in the liquefaction reactors and limited operability of the solid-liquid separation system presented problems in integrated operation over extended time periods.

Characterization of a complex mixture of aromatic and heterocyclic acids obtained from oxidation of lignite coal and its solvent-refined products

This study reports the results from the oxidation, using sodium dichromate, of a solvent-refined lignite (SRL) and its feed coal and the effects of varying the ratio of oxidant to coal. The numerous aromatic and heteroaromatic carboxylic acids isolated were identified as their methyl esters by g.c./m.s. and h.r.m.s. Oxidation of SRL with a limited amount of dichromate yielded a large number of polycyclic aromatic and heteroaromatic acids not found in the oxidation of the lignite. These results indicate that the SRL process produces highly-condensed aromatic molecules.

Evaluation of solvents for carbon-13 n.m.r. analysis of solvent-refined coals. sym-Triazine a new carbon-13 n.m.r. solvent

Solvent-refined lignite (SRL) and bituminous coals (SRC) are only partially soluble in good standard carbon-13 n.m.r. solvents. A survey of other possible solvents for SRLs and SRCs showed that sym-triazine at 86 °C solvated SRL as well as pyridine, but did not absorb in the regions of interest (5–60 and 90–160 ppm relative to TMS). Model hydrocarbons, phenols and an alcohol in sym-triazine gave aromaticities ( f a ) accurate within the standard deviation (0.01 to 0.001) when proper FT carbon-13 techniques were used. An alkene and an aliphatic amine reacted with sym-triazine and gave inaccurate values of f a .

Comparison of solvent-refined lignite with solvent-refined bituminous coals

Comparison of laboratory-deashed samples of solvent-refined lignite, subbituminous and bituminous coals on the basis of gross combustion analysis, acid and basic titres, molecular weight, nuclear magnetic resonance, ultraviolet and electron spin resonance spectra including various derived parameters indicated that there is relatively little difference between the range of values for lignite- and bituminous coal-derived solvent-refined products. The probability that coal nitrogen content is reflected in the solvent-refined product was noted.

Catalytic activities and selectivities of MoO 3NiSO 4 supported on various oxides for hydrocracking of solvent refined lignite : Novel low surface area active catalysts

The hydrocracking of solvent refined lignite (SRL) was studied over MoO 3NiSO 4 catalysts supported on TiO 2 ZrO 2, TiO 2SiO 2 and three kinds of aluminas at 450°C under an initial pressure of 2500 p.s.i. hydrogen. MoO 3NiSO 4 supported on a fibrous alumina, Al 2O 3 (FF), was found to show the highest activity, the total conversion of SRL being 92%. The activities per unit surface area of the catalysts supported on TiO 2 and ZrO 2 were much higher than those of other catalysts. A presulfided MoO 3NiSO 4Al 2O 3(FF) gave the largest amount of total liquid fractions. The best catalysts for the formation of gasoline fractions were presulfided MoO 3NiSO 4Al 2O 3(FF) and a commercially available catalyst, MoO 3NiOAl 2O 3(HT-100), which was also presulfided. It was shown that there is no correlation between acidic properties of the catalysts and their activities or selectivities.

Catalytic Hydrogenation of Solvent-Refined Lignite to Liquid Fuels

Abstract Solvent-refined lignite (SRL) can be produced by treating lignite (not dried) with CO-H2, donor solvent and high temperature. This reactive black solid softens at about 150°C, is soluble in many organic solvents, is very low in ash and sulfur, and appears to be a good feedstock for further upgrading. Thus a wide-ranging study was undertaken to determine the best reducing conditions for converting SRL to light distillable liquid fuels and/or chemical feedstocks. Batch autoclave studies were carried out in the temperature range of 375-450°C, hydrogen pressure range of 1500-4500 psi, with catalysts Ni-Mo-Al2O3, Co-Mo-Al2O3, Ni-W-Al2O3, Ni-W-SiO2-Al2O3, SiO2-Al2O3, Al2 O3, SnCl2, and presulfided catalysts Ni-Mo-Al2O3, Co-Mo-Al2O3, NiW-Al2O3. Varying amounts of the solvents tetrahydrofuran, tetralin, nap-thalene, and FS-120 petroleum fraction were also studied. Reductions without any solvent were studied too and were quite successful. The results were evaluated in terms of the amount of light liquids ...

Startup Solvent Selection for the Liquefaction of Lignite

In studies at the University of North Dakota sponsored by the U.S. Office of Coal Research, batch liquefaction tests with 15 coal-derived (C-D) and 10 petroleum-derived (P-D) potential solvents as hydrogen donors, in a 1 gal autoclave at 752/sup 0/F, 2850-3300 psig max, and at a 1 : 1 carbon monoxide/hydrogen mole ratio showed that C-D creosote oil, C-D anthracene oil, FS-120 (Gulf carbon-black feedstock), and aromatic concentrate (a heavy catalytic cracking recycle stock) should be adequate for lignite liquefaction. Compared with P-D solvents, the C-D solvents have much lower sulfur contents and higher percentages of ''standard solvent'' in their ''as-received'' form, but P-D solvents offer lower light oil yields and thus higher net SRL (solvent-refined lignite) yields, lower hydrogen requirements for hydrogenating the feed solvent, fewer plugging problems following liquefaction, and higher recycle solvent recovery. Pending further tests, enough recycle solvent should be available to make solution hydrogenation viable.