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02824 Liquefaction behavior of Point of Ayr coal
02 Liquid fuels (derived liquid fuels) Copyroiysis of coal and used tires 98lO2813 Laurent, P. et al. DGMK Tagungsber.,1997, 9703, (Proceedings ICCS ‘97, Volume 2). 837-840. Waste tyres were pyro$sed in different proportions between 560 and 760°C with coal in a 100 cm- static batch reactor m a nitrogen atmosphere. The yields and the composition of gases, oils, and chars were determined in relation to pyrolysis temperature and tyre content. Oil and gas formation is promoted with an increase in temperature. The partial substitution of coal by used tyres has a positive effect on oil production, but at high temperature, a part of oils is decomposed into gas and char. The presence of scrap tires does not extract more oil from coal, but improves the quality of the oil, increasing the yields in light aromatic compounds (BTX) and the formation of products with high value, like limonene. The mechanical properties of the chars are not appreciably modified by adding a low percentage of tyre to coal. Development of liquefaction process of plastic 98102814 waste in supercritical water Kimura, K. et al. Mifsubishi Juko Giho. 1997, 34, (6) 438-441. (In Japanese) A pilot plant of 0.5 ton/day capacity has been constructed encompassing a new elastic waste liauefaction orocess in suoercritical water. Plastic mate;ials of electric cable made of cross-linked polyethylene were successfully liquefied without coking trouble and a liquefaction yield of >80% was attained. The pilot plant tests showed good stability in daily start and stop operation. L
Economic conversion of natural gas to synthetic 98102815, petroleum liquids Aaee. M. A. Prepr. Pap. Am. Chem. Sot., Div. Fuel Chem.. 1997, 42, (2), 6i2-676. Natural gas conversion to higher hydrocarbons via Fischer-Tropsch synthesis (the Syntroleum process) is reviewed. Effect of SilAi ratio of the acid function of the 98102816 Cr,Os-ZnO/ZSM-5 bifunctionai catalyst on the transformation of - _ syngas into liquid hydrocarbons _ Erena, J. et al. Afinidad, 1997, 54, (472) 479-482. (In Spanish) The authors studied the kinetic behaviour of a Cr,07-ZnO/ZSM-5 bifunctional catalyst prepared using ZSM-5 zeolites of different Si/AI ratio. SAPO-34 silicoaluminophosphate was studied at 30 atm and 375°C showing a lower activity compared with the ZSM-5 zeolite and more rapid deactivation due to coke formation. The optimum Si/AI ratio of the ZSM-5 zeolite, which showed a good compromise between activity and selectivity, together with other properties was determined. Effects of drying and oxidation on liquefaction of 98/02817 Wyodak coal using in situ generated MoS2 catalyst at 350-425”C Song, C. S. et al. DCMK Tagungsber., 1997. 9704, (Proceedings ICCS ‘97. Volume 3) 1397-1400. In Wyodak sub-bituminous coal liquefaction in tetralin, drying and mildly oxidative drying of the coal show negative impacts on its conversion at 350°C but positive effects on runs at 425°C. Coal conversion into THFsolubles did not decrease after pre-drying of the coal in vacuum or in air before ATOM impregnation when ammonium tetrathiomolybdate (ATTM) was used as catalyst- precursor, but vacuum-drying resulted in lower oil yield. Drying also affected CO2 yields in both non-catalytic and catalytic runs. Elucidation of mechanism of coal liquefaction 98/02818 usina tritium and 35S tracer methods Godo: M. et al. Energy Fuels, 1997, 11, (3) 724-729. Using tritium and “S tracer methods under liquefaction conditions, the reactivity of hydrogen in tetralin and in Taiheiyo coal in the presence of iron catalysts and sulfur were investigated. Coal liquefaction was performed for 30 min at an initial pressure of 5.9 MPa and a temperature of 400°C in the presence of tetralin solvent and tritiated hydrogen, with and without a catalyst and “SS-labelled sulfur. The results suggest that the catalyst derived from Fe(C0)5 and sulfur was successfully dispersed in the coal and directly acted on the coal to increase both the rate of coal conversion and the tritium transfer from the nas ohase to the coal. The iron catalvsts ereatlv promoted the hydrogen eichange between the gas phase and ihe Gtralin solvent in the absence of coal. Part of the added sulfur participated in the sulfur exchange reaction with the pyrrhotite catalyst: The-amount of hydrogen incorporated into the coal was increased with sulfur addition, indicating that, during the hydrogen transfer from the solvent to the coal, sulfur promoted the formation of tetralyl radicals. 98102819 Fischer-Troosch svnthesis: orocess considerations based on performance of iion-based catalysts Raie, A. et al. Fuel, 1997, 76, (3) 273-280. For Fischer-Tropsch synthesis, alternative reactor configurations and the utilization of a low-alpha vs high-alpha iron-based catalysts were compared on the basis of actual catalyst performance. The use of coal-derived syngas with a low Hz-CO ratio requires a judicious balance between the rates of the Fischer-Tropsch and water-gas shift reactions. The hydrocarbon spacetime yield was considerably increased by using either a reactor with recycle or a series of reactors with low syngas conversion per pass instead of a single-pass reactor with high syngas conversion. Both hydrocracking and
oligomerization are involved in the production of gasoline- and diesel-range hydrocarbons by downstream processing of the Fischer-Tropsch reaction products. The difference between processing the products from a low-alpha and a high-alpha iron-based catalyst was merely in the relative sizes of the hydrocracking and oligomerization reactors required. In addition, it is advantageous to use a low-alpha catalyst from the viewpoint of FischerTropsch slurry reactor operation. 98102820 Function of hydrogenated solvent in the coal liquefaction system Hirano, K. et al. Nippon Enerugi Gakkaishi, 1997, 76, (lo), 971-979. (In Japanese) A SL batch-autoclave was used in an investigation into the influence of heavy distillate in the solvent for coal liquefaction. The following conclusions were drawn: (1) Heavy distillate in the solvent consumes a lot of hydrogen and prevents hydrogen translation in the asphaltene hydrogenating reaction, which reduces oil yield in the coal liquefaction system. (2) Donatable hydrogen in the heavy solvent equally promotes coal liquefaction reaction to that in the recycle solvent. Severe hydrotreatment of the heavy solvent increases its hydrogen donatability and oil yield in the coal liquefaction system.
A history of coal liquefaction in United Kingdom, 98102821 1967-l 992 Kimber, G. M. Prepr. Pap. Am. Chem. Sot., Dil’. Fuel Chem., 1997, 42, (I), 308-312. An overview of the coal liauefaction studies carried out bv the British Coal Utilisation Research Association., (BCURA), the National Coal Board (NCB) and the British Coal Corporation (BCC) between 1967 and 1992 at their research establishments in Leatherhead. Stoke Orchard and Point of Ayr is provided. increase of yield of lighter fraction and distillate in 98lO2822 coal liquefaction products under less catalyst addition Okuyama, N. et al. DGMK Tagungsber., 1997, 9704, (Proceedings ICCS ‘97, Volume 3) 1409-1412. Under various reaction conditions, the effect of heavy solvent on light oil production in direct liquefaction of brown coal was investigated in a 0.1 t/d continuous bench-scale unit (BSU) with iron catalyst. The heavy solvent was recycled instead of the wide boiling range solvent under the condition of recycling of the coal liquid bottoms to produce a lighter distillate. An increase in total distillate yield accompanied an increase in the recycling ratio of CLB by keeping the H2S concentration in the reactor at =I.0 vol%. The activity of recycled catalyst in the CLB was considered to be affected by HZS partial pressure in the reaction system, particularly at
Fuel and Energy Abstracts
July 1998
261
Economic conversion of natural gas to synthetic 98102815, petroleum liquids Aaee. M. A. Prepr. Pap. Am. Chem. Sot., Div. Fuel Chem.. 1997, 42, (2), 6i2-676. Natural gas conversion to higher hydrocarbons via Fischer-Tropsch synthesis (the Syntroleum process) is reviewed. Effect of SilAi ratio of the acid function of the 98102816 Cr,Os-ZnO/ZSM-5 bifunctionai catalyst on the transformation of - _ syngas into liquid hydrocarbons _ Erena, J. et al. Afinidad, 1997, 54, (472) 479-482. (In Spanish) The authors studied the kinetic behaviour of a Cr,07-ZnO/ZSM-5 bifunctional catalyst prepared using ZSM-5 zeolites of different Si/AI ratio. SAPO-34 silicoaluminophosphate was studied at 30 atm and 375°C showing a lower activity compared with the ZSM-5 zeolite and more rapid deactivation due to coke formation. The optimum Si/AI ratio of the ZSM-5 zeolite, which showed a good compromise between activity and selectivity, together with other properties was determined. Effects of drying and oxidation on liquefaction of 98/02817 Wyodak coal using in situ generated MoS2 catalyst at 350-425”C Song, C. S. et al. DCMK Tagungsber., 1997. 9704, (Proceedings ICCS ‘97. Volume 3) 1397-1400. In Wyodak sub-bituminous coal liquefaction in tetralin, drying and mildly oxidative drying of the coal show negative impacts on its conversion at 350°C but positive effects on runs at 425°C. Coal conversion into THFsolubles did not decrease after pre-drying of the coal in vacuum or in air before ATOM impregnation when ammonium tetrathiomolybdate (ATTM) was used as catalyst- precursor, but vacuum-drying resulted in lower oil yield. Drying also affected CO2 yields in both non-catalytic and catalytic runs. Elucidation of mechanism of coal liquefaction 98/02818 usina tritium and 35S tracer methods Godo: M. et al. Energy Fuels, 1997, 11, (3) 724-729. Using tritium and “S tracer methods under liquefaction conditions, the reactivity of hydrogen in tetralin and in Taiheiyo coal in the presence of iron catalysts and sulfur were investigated. Coal liquefaction was performed for 30 min at an initial pressure of 5.9 MPa and a temperature of 400°C in the presence of tetralin solvent and tritiated hydrogen, with and without a catalyst and “SS-labelled sulfur. The results suggest that the catalyst derived from Fe(C0)5 and sulfur was successfully dispersed in the coal and directly acted on the coal to increase both the rate of coal conversion and the tritium transfer from the nas ohase to the coal. The iron catalvsts ereatlv promoted the hydrogen eichange between the gas phase and ihe Gtralin solvent in the absence of coal. Part of the added sulfur participated in the sulfur exchange reaction with the pyrrhotite catalyst: The-amount of hydrogen incorporated into the coal was increased with sulfur addition, indicating that, during the hydrogen transfer from the solvent to the coal, sulfur promoted the formation of tetralyl radicals. 98102819 Fischer-Troosch svnthesis: orocess considerations based on performance of iion-based catalysts Raie, A. et al. Fuel, 1997, 76, (3) 273-280. For Fischer-Tropsch synthesis, alternative reactor configurations and the utilization of a low-alpha vs high-alpha iron-based catalysts were compared on the basis of actual catalyst performance. The use of coal-derived syngas with a low Hz-CO ratio requires a judicious balance between the rates of the Fischer-Tropsch and water-gas shift reactions. The hydrocarbon spacetime yield was considerably increased by using either a reactor with recycle or a series of reactors with low syngas conversion per pass instead of a single-pass reactor with high syngas conversion. Both hydrocracking and
oligomerization are involved in the production of gasoline- and diesel-range hydrocarbons by downstream processing of the Fischer-Tropsch reaction products. The difference between processing the products from a low-alpha and a high-alpha iron-based catalyst was merely in the relative sizes of the hydrocracking and oligomerization reactors required. In addition, it is advantageous to use a low-alpha catalyst from the viewpoint of FischerTropsch slurry reactor operation. 98102820 Function of hydrogenated solvent in the coal liquefaction system Hirano, K. et al. Nippon Enerugi Gakkaishi, 1997, 76, (lo), 971-979. (In Japanese) A SL batch-autoclave was used in an investigation into the influence of heavy distillate in the solvent for coal liquefaction. The following conclusions were drawn: (1) Heavy distillate in the solvent consumes a lot of hydrogen and prevents hydrogen translation in the asphaltene hydrogenating reaction, which reduces oil yield in the coal liquefaction system. (2) Donatable hydrogen in the heavy solvent equally promotes coal liquefaction reaction to that in the recycle solvent. Severe hydrotreatment of the heavy solvent increases its hydrogen donatability and oil yield in the coal liquefaction system.
A history of coal liquefaction in United Kingdom, 98102821 1967-l 992 Kimber, G. M. Prepr. Pap. Am. Chem. Sot., Dil’. Fuel Chem., 1997, 42, (I), 308-312. An overview of the coal liauefaction studies carried out bv the British Coal Utilisation Research Association., (BCURA), the National Coal Board (NCB) and the British Coal Corporation (BCC) between 1967 and 1992 at their research establishments in Leatherhead. Stoke Orchard and Point of Ayr is provided. increase of yield of lighter fraction and distillate in 98lO2822 coal liquefaction products under less catalyst addition Okuyama, N. et al. DGMK Tagungsber., 1997, 9704, (Proceedings ICCS ‘97, Volume 3) 1409-1412. Under various reaction conditions, the effect of heavy solvent on light oil production in direct liquefaction of brown coal was investigated in a 0.1 t/d continuous bench-scale unit (BSU) with iron catalyst. The heavy solvent was recycled instead of the wide boiling range solvent under the condition of recycling of the coal liquid bottoms to produce a lighter distillate. An increase in total distillate yield accompanied an increase in the recycling ratio of CLB by keeping the H2S concentration in the reactor at =I.0 vol%. The activity of recycled catalyst in the CLB was considered to be affected by HZS partial pressure in the reaction system, particularly at
Fuel and Energy Abstracts
July 1998
261