04 By-products related to fuels

96m9aa Productlon of activated carbon from Canadlan coal by chrmlcal actlvatlon Havashi. J. et al., Coal Sci. TechnoL. 1995. 24, 1121-1124. Aciivated carbon &as prepared from &nadian coal by chemical activation with ZnCl, and NaOH. The influences of preparation conditions on pore structure of activated carbon was investigated.

S6/QS969 Productlon of actlvated carbon6 from Illlnol8 coals HimhI E. J. et al., Preur. Pao.-Am. Chem. Sot., Div. Fuel Chem., 1996. 41; $j, 241-245. * - The objective of this study was to demonstrate that activated carbon with acceptable commercial properties could be made from Illinois Basin coal using a two- and three-step process.

96lo599o Productlon of carbon adeorbentr from brown coal Pokonova, Y. V. Carbon, 1996, 34, (3), 411-415. A method was developed for the production of carbon adsorbents from brown coal and the oroducts analvzed. A mixture of brown coal with shale resin and propane &phalt enables one to trial process, carbon absorbents with lu

reduce, through existing indus- .$: mechanical strength, low ash

content, and sufficiently large micro 8”

revolume, 21.4 kJ/mol, that can be utilized in a

heat of adsorption 20.4- sorption-desorption processes remov-

ing small-size molecules from gaseous media, for water desalination and for the treatment of phenol effluents.

96105991 Productlon of organic aclda In hlgh yields from brown coal8 through the llquld phase oxldatlon wlth H,O, at low temperature Miura, K. and Mae, K. 1996, 41, (2), 734-738.

Prepr. Pap.-Am. Chem. Sot., Div. Fuel Chem.,

Low-rank coals were subjected lo low-temperature liquid-phase oxidation with 30% aqueous &O, at 40, 60, and 80” for several hours reaction time, for the production of water-soluble organic acids. At 60”, the solid residue yield decreased to 55% after 2 h, and decreased gradually lo 19% after 24 h; at 80°, the coals decomposed more rapidly, with a solids yield of 15% after 4 h.

96105992 Productlon of porous material from coal ash dla- charged from fluldlzed bed combuator Okajima, T. et al., Coal Sci. Technol., 1995, 24, 1983-1986. Describes the manufacture of heat insulating bricks from batches consist- ing primarily of pressurized fluidized bed coal combustor fly ash and boiler ash. The ash mixture slurry is moulded in wooden forms, and the network structure consisting of acicular growth of crystals forms during drying.

96105993 Radlatlon-Induced diamond formatlon In uranlum- rich carbonaceour materials Daulton, T. L. and Ozima, M. Science (Washington D.C.), 1996, 271, 1260-1263. Describes how nanometer-sized diamonds were identified by transmission electro microscopy in a uranium-rich, coal-like carbonaceous assemblage of Precambrian age.

96105994 Recovery of hard aclda and soft bases from decomposed coal Kramer, G. M. et al., (Assigned to) Exxon Research & Engineering Co., USA, US. Pat.5,492,618, Feb. 1996. Describes an improved process for recovering hard acids and soft bases used to decompose coal in which finely divided coal particles are contacted with a hard acid in the presence of a soft base at temperatures from 0” to 100”.

96106995 Recovery of lime, sulfur, and Iron from gypsum and pyrite wastes Kutsovskaya, M. L. et al., Ind. Eng. Chem. Res., 1996, 35, (S), 1725-1735. The paper discusses the feasibility of a new approach of recovery of lime, iron, and sulphur products from gypsum ai& pyrite, two majbr wastes generated bv the coal combustion Industry. By thermal decommsition of pyrite, 420/ of the sulphur is recovered-and pyrrhotite is produced. A thermodynamic analysis showed that the recovery of iron and lime from pyrrhotite and gypsum is a single-stage process is not feasible. Instead, the process has to consist of two subsequent stages. The first comprises the ieduction of pyrrhotite with carbon in-the presence of lime to produce iron, calcium sulphide, and carbon monoxide, followed by reaction of calcium sulphide with gypsum to produce lime and a concentrated sulphur dioxide stream.

96105996 Reutlllzatlon studies for brown coal fly ash Lenz, U. et al., Coal Sci Tech&., 1995, 24, 1995-1998. Describes the utilization of coal fly ashes, including chemical composition of the ash, suitability of ash as lime fertilizer, use of fly ashes in forestry, use of ash as lime substitute for the production of sand lime bricks, and the use of ash in earthworks and foundation engineering.

99/0599? The role of carbon black/coal-tar pitch Interactions In the early stage of carbonlzatlon Menendez, R. er aL, Carbon, 1996, 34, (7), 895-902. The study was undertaken to gain further insight into the types of interac- tion between pitch and carbon black occurring during thermal treatment in the initial stages of carbonization, and the effects on subsequent coke structure.

96/05996 Roller compacted base course construction ualng lime rtablllzed fly ash and flue gas deaulfurlzatlon sludge byproduct Beeghly, J. H. (21. 540-548.

Prepr. Pap.-Am. Chem. Sot., Div. Fuel Chem., 1996, 41, . I .

Describes how dewatered calcium sulphite and calcium sulphate sludges from unoxidized flue gas desulphurization processes at coal fired power plants can be mixed v&h coal -fly ash and-lime to cause a cemeniitious chemical reaction used to construct a roller compacted base source or an impermeable pond liner.

96/05999 Separation of fly ash using denalty gradient centrltugatlon Palmer, S. R. et al., Coal Sci. Technol., 1995, 24, 1999-2002. Discusses how fly ash can be separated based upon density differences between different particles and that both bulk and trace element chemicals vary with particle density. It is clear that most of the trace elements are associated with the denser particles of fly ash. The data indicates that significant improvements in leachate quality could be achieved by elimi- nating the fly ash of highest density from any products that might be formed.

96/06000 Single bed pressure awing adsorption process to generate hlgh purity nltrogen LaCava, A. 1. and Lemcoff, N. 0. Gas Sep. Purif, 1996, 10, (2), 113-115. The separation of air for the production of nitrogen by pressure swing adsorption over a carbon molecular sieve is kinetically based. The basic stens involved in a cvcle are tvoicallv oressurization. hieh uressure adsom- tioh, countercurrent blowdo& and ‘v&t. Simulations &&es with D&S (Dynamic Adsorption Process Simulator) were performed 10 analyze the effect of the pressurization rate and bed length on the performance of a single bed nitrogen pressure swing adso&on unit in the high purity region.

96/06001 Solublllty of C, In alcohols and alkanea Heymann, D. Carbon, 1996, 34, (5), 627-631. The solubility of C was determined at room temperature in seven normal alcohols, four iso-a cohols, four diols, one trial, and seven alkanes. It was 9” discovered that C, forms supersaturated solutions with alcohols and alkanes. The enigmatlcally low solubility of C, in octane, observed in previous studies, was confirmed.

96/06002 Structural features and formation mechanlam of soluble fractions of meaoohaae Ditch derived from 1.2.4.5. tetramethylbenzene methyl&e-bridged ollgomer ’ ’ Song, H. et al., Fuel, Sep. 1996, 75, (ll), 1331-1338. A mesophase pitch which has 100 vol.% anisotropic content, low softening point, high solubility and good fluidity was prepared at relatively low iemperatures from i,2,4,5&amethylb&zene oligomers cross-linkkd by methylene bridges and subsequent heat treatment. Electron impact mass soectrometrv. field desorotion mass soectrometrv and ‘H and ’ C nuclear iagnetic re&nance etc. Gere used to characterizk the structural features of soluble fractions of the mesophase pitch. The results show that the mesophase pitch contains many-methyis and some amount of naphthenic groups. The molecules in mesophase pitch appear to have kata-type aro- matic skeleton.

96/06003 Studies of the role of water In the electrocatalyalo of methanol oxidation Lin, A. S. et al., J. ofPower Sources, Jan. 1996, 58, (I), 67-72. The oxidation of methanol has been carried out on electrodes prepared by evaporating Pt directly onto a Nafion membrane and then introducing the methanol either in the Pas-fed mode or dire&Iv from the electrolvte in the electrolyte-fed mode. 17 was found that the oiidation carried oi using a gas-fed electrode was shifted 100-150 mV more cathodic than the electro- iyte-fed electrode. A similar set of experiments was carried out using hydrophobic gas-diffusion electrodes and similar results were obtained.

96/06QO4 A study on co-carbonlzatlon behavlour of coal tar and petroleum pitch Shim, H. B. et al., Han’guk Chaelyo Hakhoechi, 1996, 6, (2), 138-144. (In Korean) The possibility was evaluated for using a coal tar pitch blended at a ratio of 10 to 70 wt.% with petroleum pitch of different carbonizing characteristics as the matrix of the carbon-carbon composites.

Fuel and Energy Abstracts November 1996 425