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A commercial coal liquefaction catalyst, Amocat 1A, has been subjected to a deactivation study in a laboratory catalytic coal liquefaction microreactor. Carbonaceous and metal deposits were the two major factors causing catalyst deactivation. The carbonaceous material deposited primarily in the interior of the catalyst particle and clogged the pores in a uniform manner. The metals deposit was rich...
Experiments were conducted in an externally heated drop-tube furnace to assess the effectiveness of the chemical calcium magnesium acetate [CMA, CaMg 2 (CH 3 COO) 6 ] as a combustion catalyst and a coal pretreatment agent for reducing SO 2 emissions. Bituminous coal particles of two distinct sizes, pulverized (75-90 μm) or micronized and beneficiated (mean diameter...
This work focusses on the thermal and chemical changes taking place on a low rank coal when it is subjected to hydropyrolysis conditions with Red Mud (RM) as the catalytic precursor. For each run, 5 g of coal were pyrolysed in a swept fixed bed reactor (SFB) at 40 kg/cm 2 hydrogen pressure. The variables of the process were: temperatures ranging from 400 to 600°C; 0.5 and 2 l/min of hydrogen...
Hydrocracking of hydrotreated Israeli shale oil and its atmospheric residue was studied at 50atm hydrogen pressure, LHSV 0.5-4.4h -1 , temperature 350 o C and V H2 1500Nl/l in a fixed bed reactor pilot plant with two Ni-Mo-zeolite catalysts based on mono-(HY+Al 2 O 3 ) and bizeolite (HY+H-ZSM-5+Al 2 O 3 ) supports. Desulfurization and...
Carbonaceous deposits on finely dispersed MoS 2 particulates and a NiMo-supported catalyst, recovered from coal extract hydrocracking experiments, have been examined. Large surges in carbon deposition on catalyst surfaces were observed when using fresh catalyst and fresh feed. When using fresh feed with re-used catalyst, additional but smaller surges in deposition were found. The compositions...
Catalysts for coal conversions are overviewed in liquefaction, gasification, upgrading of coal liquid, flue gas cleaning, and synthetic gas conversions to find bases for innovative catalytic coal conversions of the next generation. Selection of active species, catalyst supports and their optimized combinations are keys to developing such processes. Carbons or perovskite type supports are claimed to...
We have found that adding a proper amount of water can dramatically improve conversion of a sub-bituminous coal in solvent-free liquefaction under at 350°C using ammonium tetrathiomolybdate (ATTM) as precursor to dispersed MoS2 catalyst H2 pressure. However, adding water to catalytic reactions at 400°C decreased coal conversion, although water addition to the non-catalytic runs was slightly beneficial...
Two Turkish lignites were extracted with tetralin in a batch autoclave under nitrogen atmosphere. Fe 2 O 3 , Mo(CO) 6 , MoO 3 or Al 2 O 3 were used as the added catalyst. The isothermal extraction temperatures ranged from 325 to 425 o C, the starting nitrogen pressure ranged from atmospheric to 5MPa, the isothermal extraction periods ranged from...
Hydrogen is a key reagent in the petroleum and petrochemical industry. Thus, the intrinsic solubility of hydrogen in organic liquids of industrial interest is an important parameter for process design and process modeling. The existing hydrogen solubility data base for industrial fluids is limited and does not account for the potential impact of trace additives such as clay and catalyst fines, on...
A study of the steam gasification of Eucalyptus chars has been carried out, using Li, Na and K chlorides as catalysts, in order to characterise the gas phase with a view to its energy use, analysing the influence of steam flow rates, initial mass of char, particle size and temperature. The main gases generated were H2, CO and CO2, with a higher heating value between 9 and 10MJ/Nm3. The presence of...
Effects of the process parameter on the distribution of the inherent sulphur among the products of the catalytic liquefaction of two Turkish lignites have been investigated. The dissolution reactions were carried out in tetralin at 350-425 o C under nitrogen atmosphere. Fe 2 O 3 , Mo(CO) 6 , MoO 3 or Al 2 O 3 were used as the added catalysts...
Strong expectations exist for future use of carbon nanotubes as composite materials in a large number of industries. Production cost and control of the purity and properties of such materials will influence the impacts nanotubes on the chemical, computer and construction industries. As a source material, coal is cheap and abundant, and has unique chemical structure, therefore, may be utilised in the...
The CO 2 gasification of maceral chars was performed using CAHN TG-151 pressurized thermobalance under different conditions. The effect of mineral in macerals and catalyst on the gasification reactivity of maceral chars and the gasification kinetics were systematically investigated. The results showed that the apparent gasification rate of maceral chars depends on the temperature, pressure,...
Six kinds of straight run light gas oils were tested under various conditions in high pressure fixed bed reactor. First the formula of the corrected WAT (weight average temperature) normalized to the standard conditions was made by trial and error method, using the parameters chosen by the information of literature. Next the analysis of datamining method (ID3) and correlation coefficient were applied...
Al-MCM-41 type mesoporous catalysts were used for converting the pyrolysis vapours of spruce wood in order to obtain better bio-oil properties. Four Al-MCM-41 type catalysts with a Si/Al ratio of 20 were tested. The catalytic properties of Al-MCM-41 catalyst were modified by pore enlargement that allows the processing of larger molecules and by introduction of Cu cations into the structure.Spruce...
This paper reports the significant enhancement of hydrogen production during the gasification of Victorian brown coal with steam using iron as a catalyst. Iron was loaded into the acid-washed Loy Yang brown coal using ferric chloride aqueous solution. Gasification experiments were carried out using a quartz reactor at a fast particle heating rate. The yield of char was determined by directly weighing...
For the first time an experimental set-up, called atmospheric pressure temperature programmed reduction (AP-TPR) applied in the speciation study of sulphur compounds in coal, has been used in the hydrodechlorination study of polychlorinated biphenyls (PCBs) with several specifically designed catalysts. Quantitative results concerning the degree of dechlorination were obtained using a potentiometric...
Coal mine methane (CMM) is not only a greenhouse gas but also a wasted energy resource if not utilised. Underground coal mining is by far the most important source of fugitive mine methane, and approximately 70% of all coal mining related emissions are from underground ventilation air. Hence, research and development on mine methane capture, mitigation and utilisation should focus on methane emitted...
This paper is concerned with the effects of adding tin and/or titanium dopant to sodium aluminium hydride for both dehydrogenation and re-hydrogenation reactions during their reversible storage of molecular hydrogen. Temperature programmed decomposition (TPD) measurements show that the dehydrogenation kinetics of NaAlH 4 are significantly enhanced upon doping the material with 2mol% of tributyltin...
Catalyst plays an important role in direct coal liquefaction. This paper focuses on the catalytic behavior of a novel SO42-/ZrO2 superacid catalyst in coal hydro-liquefaction. A series of hydro-liquefaction experiments were conducted under mild conditions – 400°C, 30min and H 2 initial pressure 4MPa in a batch autoclave with a volume of 100ml. The catalytic property of SO42-/ZrO2 was compared...
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