Manganese(II) complexes with linear potentially pentadentate Schiff base ligands have been prepared and characterized. Their reactions with dioxygen and nitric oxide has been studied. The ligands were synthesized from substituted salicylaldehydes and selected hiamines containing a central nitrogen donor. The five-coordinate complexes assume a distorted trigonal bipyramidal structure. The manganese(II) complexes are unstable in the air and all of them react with dioxygen in solution. Intro cases dimeric µ-peroxo dioxygen adducts were formed which are stable in air. These two complexes demonstrate reversible coordinating ability for dioxygen under mild conditions. The manganese(II) complexes react with nitric oxide when in solution when no steric problems are presented by the central donor. All the manganese(I) nitrosyls so formed demonstrate reversible coordinating ability for nitric oxide under mild conditions. Some steps in the characterization of a Solvent Refined Coal has been presented. A novel chromatographic column design has been developed which allows the rapid quantitative GPC separation of coal liquid products on a preparative scale, Among several packings that were examined Bio-Beads S-X4 proved to be the superior material. Molecular weights on each fraction were determined. Quantitative determination of metal content in the Solvent Refined Coal were made using flameless atomic absorption spectrometry. The Solvent Refined Coal was shown to contain substantial quantities of catalytic metals and metals of environmental concern. Electron Spin Resonance measurements yielded signals assignable to organic free radicals and iron(III) were observed. / Ph. D.

A large percentage of Southern Appalachian coal reserves are located in seams less than 36" thick. As thicker and currently more mineable, deposits are exhausted, methods of underground thin-seam extraction will have to be developed. These methods must be capable of removing coal efficiently and economically. Past experience with highwall mining of thin-seam coal has indicated that recovery rates tend to be lower than in conventional operations. It is suspected that this will also apply to underground thin-seam mining, regardless of proposed technology or mining method. A method of increasing recoveries from thin-seam mining operations is necessary in order to exploit thin-seam reserves. Backfilling is one alternative that may find applicability in thin-seam coal mining. The ability of backfill to provide additional ground support may enhance coal recovery by allowing for the design of undersized pillars. Backfill has been used extensively in hard rock mining but has found limited use in coal mining. Its adaptability to thin-seam coal mining has been examined and is presented in this thesis. Backfill is capable of providing additional ground support by restricting lateral deformation of surrounding coal pillars and roof. This additional support can result in significant increases in recovery from thin-seam coal deposits. However, the overall feasibility of backfill is dependent on the in situ behavior of the fill material, the properties of the fill, the effects of the filling method on the total mining operation, and the cost of filling per extra ton of coal recovered. The influence of these parameters has been studied and indicate that, in certain situations, backfilling for the purpose of increasing recovery rates from thin-seam coal mines is feasible. / Master of Science

On the basis of the results obtained in this investigation, the following conclusions were drawn: 1. Midlothian coal was 31.3 percent liquefied by hydrogenation at atmospheric pressure and 185°C after 72 hours of reaction in a tetralin vehicle and using stannous sulfide as a catalyst. 2. The liquid product of the hydrogenation of Midlothian coal consisted of approximately 50 percent light oil boiling below 200°C., 20 percent middle oil, boiling from 205°C. to 235°C., and 30 percent heavy oil or tar residue. 3. The light oil fraction of the hydrogenated product of Midlothian coal consisted of 5 to 10 percent each of olefins and saturated hydrocarbons, with the remainder being aromatic compounds. 4. The rate of liquefaction of Midlothian coal by hydrogenation researched a nearly constant value of 0.41 grams of liquid product produced per 100 grams of coal per hour after 24 hours of reaction. 5. During the first 24 hours period of hydrogenation, the volatile matter content of the carbonaceous residue increased by 5.0 percent after which the volatile matter decreased by 6.2 percent during the following 48 hour period. 6. During the hydrogenation reaction of 72 hours the fixed carbon content of the coal was reduced by 18 percent. 7. During the latter 48 hours period of reaction, 65 percent of the liquefaction was from the volatile matter constituents and 35 percent of the liquidation was from the fixed carbon components. / M.S.

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Call number: LD2668 .T4 1931 N51

This thesis presents research on the co-gasification characteristic of biomass and coal, and mathematical modelling of the co-gasification process in two main parts: i) experimental investigation and mathematical modelling of reaction kinetics of steam gasification of single char particles of pure coal, pure biomass, and blended coal and biomass; and ii) Experimental investigation and mathematical modelling of gasification characteristics of biomass, coal and their blends in pilot scale gasifiers. From the char reactivity study, the instinct difference in gasification characteristics of the two chars has been explained and reactivity of blended char can be predicted. In the pilot scale gasifier study, effects of blending ratio in feedstock and operating conditions on co-gasification of biomass and coal were investigated.

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