Abstract: A systematic research on the combustion characteristics of Guizhou lignite, Sanjiang coal and Sanjiang char had been done using STA 409C Netzh- thermogravimetric analyzer. The effects of particle diameter and heating rate on maximum mass loss rate, ignition point and combustibility were analyzed. The decrease of particle diameter can reduce the ignition point and improve the combustibility. When particle size is 100～120 mesh and heating rate is 25 ℃/min, the combustibility of samples is the best. The combustion reactions are one-order reaction and kinetics parameters (activation energy E and frequency factor A) were obtained by the method of Coats-Redfern basing on experimental data. Activation energy of Guizhou lignite, Sanjiang coal and Sanjiang char are 100.0～163.6 kJ/mol, 73.4～161.2 kJ/mol, 68.3～178.1 kJ/mol.
Abstract: The liquid products from co-pyrolysis of Dayan lignite (DY) and legume straw (LS) and from pyrolysis of the single fuel were classified into asphalts, phenols, aliphatic, aromatics and polar fractions by solvent extraction-column chromatography. Compared with the calculated yield of asphalts, i.e. the mass weighted mean value 19.0% from pyrolysis of the single coal and biomass, the experimental yield from co-pyrolysis decreased to 11.4%, and the aromaticity of the co-pyrolysis asphalts increased. At the same time, the yield of light molecular weight phenols, methylphenol, dimethylphenol and their derivatives increased at about 5% during the co-pyrolysis; while the content of aliphatic hydrocarbons with long chains decreased. The content of decalins was 43.37% in aromatic fraction of the co-pyrolysis tar, whereas it was almost not found in the tars from pyrolysis of the individual fuel. These results verified that the synergy existed during co-pyrolysis of coal and biomass under the experimental conditions. It was contributed to the reactions such as hydropyrolysis and hydrogenation during co-pyrolysis of coal and biomass under the hydrogen atmosphere mainly supplied by biomass pyrolysis. Co-pyrolysis of coal and biomass favors producing low molecular weight compounds and improving the quality of the liquid product.
Abstract: Direct liquefaction of cornstalk cellulose in sub-/super-critical ethanol was investigated with a batch reactor at 200～330 ℃ and an initial usage of ethanol varying from 0 to 150 mL. The results show that the reaction temperature, ethanol quantity and retention time significantly influence the direct liquefaction of cornstalk cellulose. The yields of heavy oil and gases increase by 12.55% and 28.83% respectively, depending on reaction temperature from 200 to 330 ℃. The reaction pressure increases with the increment of ethanol, and the yield of residues and gases reduces by 11.10% and 8.44% in supercritical ethanol compared with that from thermal cracking without ethanol. The FT-IR analyses for residues and GC/MS measurements for the oils reveal that cornstalk cellulose was liquefied through deploymerization in supercritical ethanol, and the main components of oils are ketone and ethyl ester and their derivatives.
Abstract: The quality of bio-oil is affected by solid particles. X-Ray Diffraction, Fourier Transform Infrared Spectroscopy and Inductively Coupled Plasma were used to investigate features of the particles. The results show that the content of particles varies with pyrolysis technology, and there are more particles in bio-oil obtained from circulating fluidized bed. The particles mainly consist of char, ash and a small amount of organic polymer. The major components of the ash are metal elements and SiO2, while of the polymer is oligomer with lignin structure. The content of metal elements is influenced by the characteristics of raw material for pyrolysis.
Abstract: The methods of acid-base separation and extraction-chromatography were used to separate Longkou shale oil into acid fractions, basic fractions and five neutral fractions. The molecular structure and mass distribution of oxygen compounds in Longkou shale oil were investigated using gas chromatography-mass spectrometry (GC-MS) and negative-ion electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The results of GC-MS show that the oxygen compounds in acid fractions involve phenols, indanols, naphthols, phenylphenols, fluorenols, phenanthrenols, and carboxylic acids ranging from C5 to C16. The oxygen compounds in neutral fraction 4 and 5 involve aliphatic ketones ranging from C9 to C32 and lipid compounds. The results of ESI FT-ICR MS show that the class species of O1, O2, O3, N1O1, N1O2 are found. The O1 and O2 have the higher ion intensity among the species in shale oil. The m/z range of shale oil is from 150 to 600. It is obviously that Longkou shale oil is mainly composed of small molecular compounds which are polymerized by Van der Waals force and hydrogen bonding. The properties of shale oil are similar to macromolecular compounds. Longkou shale oil has O1, O2, O3 compounds mainly with DBE of 1 and 4, suggesting that Longkou shale oil can be regarded as a less biodegraded oil.
Abstract: The influence of asphaltene contents on the yield and properties of hydrotreated residue was studied in an autoclave by using the residue of Tahe deasphalted oil (DAO) mixed with different contents of asphaltene. The results show that the yield of hydrotreated residue and the ratio of the asphaltene in hydrotreated residue plus coke to the asphaltene in feedstock decrease with the increasing of asphaltene content. The asphaltene can be converted to light oil more easily at the selected reaction conditions when the asphaltene content in feedstock is high. The molecular weight, the H/C mol ratio, the sulfur content, the aromatic fraction and the resin of the hydrotreated residue decrease. However, the density, the nitrogen content, the saturation fraction and the asphaltene increase for the hydrotreated residue. The removal rate of sulfur and nitrogen first increases and then decreases with the increasing of asphaltene content in feedstock.
Abstract: Iron-manganese catalysts were prepared by co-precipitation method. Characterization of catalysts was carried out by using X-ray diffraction (XRD), scanning electron microscopy (SEM), temperature program reduction (TPR), N2 adsorption-desorption measurements. The results from catalytic performance tests in Fischer-Tropsch synthesis showed that the iron-manganese catalysts are supersensitive to catalyst composition and materials source. It was found that C2～4 light olefins increased while CH4 and CO2 decreased by using iron-manganese catalyst prepared from iron (Ⅱ) sulfate (A catalyst). The activity and selectivity of A catalyst was studied in different operational conditions. The results showed that the best operational conditions for C2～4 light olefins production were H2/CO=1/1 (GHSV=2 400 h-1) at 260 ℃ under 0.3 MPa total pressure.
Abstract: The preparation of FAU-type zeolite films on FeCrAl grids by hydrothermal synthesis was studied with an emphasis on effects of ageing of the synthesis mixture, seeding of the support and addition of polyvinyl alcohol (PVA) in the seed solution. The catalytic activity of FAU-type zeolite films was evaluated for cracking of a model endothermic fuel (n-octane). The results show that coating of the support with Y-type zeolite seeds could increase the loading of zeolite crystals on the support and thus facilitate to grow a continuous and dense FAU-type zeolite film around the wire, especially using an aged synthesis mixture. Under the same synthesis conditions, the loading of zeolite crystals was enhanced using a PVA-containing seed solution for seeding. The initial conversion of n-octane at 500 ℃ was higher over FAU-type zeolite films (7.2%～13.2%) than that over the bare support (4.4%). The activity of zeolite films depends on not only the loading of zeolite crystals but also the morphology of the film.
Abstract: Mesoporous MCM-48 molecular sieves were synthesized in a fluorinecontaining system using tetraethylorthosilicate (TEOS) as silica source and cetyltrimethylammonium bromide (CTAB) as template. To investigate the influence of various factors for synthesis on the structure and properties of the MCM-48 molecular sieves obtained, they were characterized by Xray diffraction (XRD), N2 adsorptiondesorption and transmission electron microscopy (TEM). The results showed that under the optimal conditions, i.e. a CTAB/Si ratio of 0.65 and crystallization at 393 K for 24 h, the assynthesized MCM-48 exhibits high crystallinity with a specific surface area of 1 305 m2/g and an average pore size of 2.416 nm.
Abstract: The influence of the temperature of precipitation and aging on the performance of the CuO/ZnO/Al2O3 catalyst used for methanol synthesis was studied in a slurry reactor. The catalysts and precursors were characterized through XRD, BET, FT-IR and XPS. The results show that the phases of the precursors are mainly consisted of malachite (Cu2(CO3)(OH)2) and zinc malachite ((Cu,Zn)2(CO3)(OH)2), the crystallinity degree of the precursor that precipitated at 70 ℃ and aged at 80 ℃ is proper, and the performance of the catalyst from the precursor is optimal, with its CuO phase dispersing homogeneously, the electron binding energy of Cu element shifting the largest and the electron binding energy of Zn element shifting the minimum. Its space time yield and deactivation rate reach 153.3 g/(kgcat·h) and 1.44%/d respectively.
Abstract: ZSM-5 molecular sieves with a uniform particle size from 0.1 to 14 μm were hydrothermally synthesized by using tetrapropylammonium hydroxide (TPAOH) as the template and polyethylene glycol (PEG) as a co-template. The ZSM-5 samples were characterized by XRD, SEM, BET, Py-IR, NH3-TPD and ICP and their catalytic performance in the conversion of methanol to hydrocarbons were investigated. The results indicated that the crystal size of ZSM-5 molecular sieves can be regulated by adjusting the quantity of PEG, silica source and water content in the precursor gel as well as controlling the aging and crystallizing conditions. The ZSM-5 molecular sieves with smaller crystal sizes exhibit higher conglomeration degree, Si/Al ratio and surface area than those with large crystal sizes, but lower crystallinity, BrØnsted acid density and total acid quantity. When used as the catalysts in methanol conversion to hydrocarbons, the crystal size of ZSM-5 molecular sieves has a significant effect on their catalytic stability and the products distribution. The catalyst with smaller crystal size shows much higher stability and selectivity to the light alkanes of C1～C4; an increase in the crystal size can enhance the formation of C5+ and aromatic products but lead to a significant decline in its stability.
Abstract: The composites with mesoporous and microporous structure were obtained by treatment of ZSM-5 zeolite in mixed alkali aqueous solution of tetrapropylammonium hydroxide and inorganic base NaOH. The products were characterized by XRD, N2-adsorption/desorption, NH3-TPD, SEM and so on. The results showed that the alkaline solution would cause the zeolite desilication and dealumination and either decreasing the TPA+/OH- ratio or prolonging the alkali treatment time will cause reduction of micropore structure and increasement of mesopore amount increasingly while keeping the concentration of OH- at a fixed value. And meanwhile, the treatment also changed the acidity of zeolite. Mixed alkali treatment with proper TPA+/OH- ratio could preserve micropore structure to the maximum extent while formed the mesopore, reduce zeolite’s strong acid quantity and increase the selectivity of propylene when performanced on methanol-to-olefins (MTO) reaction. Compared with the inorganic base NaOH, the modification rate of zeolite by TPAOH was slower, milder and more controllable that could act as pore-growth moderator.
Abstract: A series of TiO2-Al2O3 composite supports with different TiO2 contents were prepared by sol-gel method and then supported nickel catalysts (NiO/TiO2-Al2O3) were obtained by impregnation with NiO/TiO2-Al2O3 as the supports. The effects of TiO2 promoter content and reaction temperature on the performance of TiO2-Al2O3 catalysts in CO methanation were investigated. The results showed that the nickel catalyst supported on the TiO2-Al2O3 composite containing 30% TiO2 exhibits the highest activity for CO methanation under a temperature from 350 to 450 ℃. BET, XRD and H2-TPR characterization results indicated that the addition of TiO2 promoter can restrain the formation of Ni/Al2O4, improve the dispersion of NiO, avoid the formation of large NiO granules, and make NiO reduction easier, which can then enhance the activity of the nickel catalysts in CO methanation.
Abstract: Supported Cu catalysts were prepared by wetness impregnation method and used in the hydrogenolysis of glycerol to l,2-propanediol. The catalysts were characterized by means of XRD, H2-TPR and NH3-TPD and the influence of temperature, pressure, reaction time and catalyst reusing on its catalytic activity in glycerol hydrogenolysis was investigated. The results showed that the catalytic activity is strongly dependent on the support and proper acidity is essential for the hydrogenolysis. 8Cu/γ-Al2O3 catalyst exhibits high activity and stability; after reaction over it for 6 h under the optimal reaction conditions of 513 K, 6 MPa, catalyst amount of 2.5%, with 10% glycerol aqueous solution as feed, the conversion of glycerol and the selectivity to 1,2-propanediol reach 88.4% and 86.2%, respectively.
Abstract: Three CuAl hydrotalcite-like compounds (CuAl-HLc) with Cu/Al atomic ratio of 2.0, 3.1 and 4.1 were prepared by a co-precipitation method and calcined to convert into CuAl mixed oxides. The CuAl mixed oxide with Cu/Al atomic ratio of 3.1 was incipiently impregnated by alkali metal (Na, K, Cs) salt solution to prepare the modified CuAl mixed oxide catalysts. The properties of the catalysts were characterized by AES, XRD, FT-IR, BET, H2-TPR and XPS techniques. The effect of CuAl mixed oxide compositions, alkali metal types and potassium precursors on catalytic activity for N2O decomposition in the presence of oxygen were investigated. It is revealed that the catalytic activity of CuAl mixed oxides impregnated by K2CO3 solution is higher than that of Na2CO3 and Cs2CO3 doped catalysts. In addition,the catalytic activity of CuAl mixed oxides can be largely enhanced by the addition of K species from the precursors of K2CO3 and K2C2O4, whereas KNO3- and CH3COOK-doped catalysts show a lower activity than sole CuAl oxide. The optimal K-doped catalyst exhibits a good activity for N2O decomposition in the presence of oxygen and steam.
Abstract: The cordierite honeycomb ceramics (CC) was coated with Mn, Cu, Ce modified TiO2, and W modified V2O5 in sequence by coating method. A series of monolith catalysts were evaluated at 120～550 ℃ for the selective catalytic reduction (SCR) of NO by urea. Compared to commercial catalyst V2O5-WO3/TiO2, the SCR performance was significantly improved between a wide temperature with the introduction of Mn, Cu, Ce. The results of characterization suggested that the activity improvement may be contributed to the suitable acidity and basicity of catalyst surface, the high ratio of V4+/V5+, the existence of anatase phase TiO2 and the good redox capability of complex catalyst. This study provides a potential catalyst system for the removal of NOx from diesel engines.
Abstract: Titania-pillared clay (Ti-PILC) was prepared from butyltitanate, then Mn-CeOx/Ti-PILC was prepared by impregnating method on the Ti-PILC. The catalysts were characterized by BET, FT-IR, XRD, XPS and NH3-TPD. The results showed that, the pillaring process was efficient. Active components exist in Mn2O3 and CeO2 in catalyst Mn-CeOx/Ti-PILC which was a porous mesopore material with high BET surface area(133.7 m2/g), the activity test also indicted that this catalyst had good de-NOx activity, the removal efficiency could reach 83.1% even at 180 ℃.
Abstract: The hydrotreating catalysts were prepared using Ni and W as active metals. The dispersity and sulfuration of the active metals were adjusted by adding organic modifiers to the Ni and/or W impregnation solution. Based on the experimental results, it was found that the dispersity of the active metals on the catalyst support was improved with organic modifiers dissolved in Ni and/or W impregnation solution. And increasing the amount of organic modifiers can not only increase the dispersity of main active phase WO3 on the support, but also promote the formation of highly active nickel species in octahedral sites and of high hydrogenation phase NiWO3. The calcination temperature can adjust the dispersity of active metals and acidity of the catalysts. The catalysts treated at optimized calcination temperature have appropriate ratio of weak and strong acidity sites and better hydrodesulfuration and hydrodenitrofication performance.
Abstract: A carboxyl-functionalized ionic liquid, 1-methyl-3-methylcarboxylate imidazolium tetrafluoroborate ([cmmim]BF4), was applied as the catalyst and extractant in the oxidative desulfurization system for the removal of dibenzothiophene (DBT) in the presence of H2O2 in model oil. Several parameters including the amount of hydrogen peroxide, temperature and reaction time were investigated. The catalyst used shows a good activity with a DBT conversion of 100% at 60 ℃, O/S mol ratio 6 and the reaction time of 80 min. The activity of ionic liquid BF4 decreases little after recycling for 4 times.
Abstract: A novel TiO2-aluminum silicate fiber nanocomposite was prepared by sol-gel method, and used to remove the elemental mercury from a simulated coal-fired flue gas under UV irradiation at a wavelength of 253.7 nm. The effects of SO2, NO and temperature on the photocatalytic removal of mercury were tested. The result shows that SO2 has a stimulative effect on the photocatalytic removal of mercury at ambient temperature. The mercury removal can reach to 93% when the SO2 concentration is 1 200 μg/m3. However, NO shows an inhibitory effect on the elemental mercury removal, and the removal efficiency decreases with the increasing of NO concentration. At high temperature, the effects of SO2 and NO on the photocatalytic removal of mercury are the same as those at the normal temperature. The mercury removal efficiency decreases as the temperature increases. Elevating temperature shows an inhibitory effect on the photocatalytic removal of mercury.
Abstract: Li4SiO4 used as a revolving CO2 absorbent at determinate temperature can be synthesized with SiO2 and Li2CO3 by solid state reaction at high temperature. The crystal structure and microstructure of Li4SiO4 were characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM), respectively. The CO2-adsorption capability of Li4SiO4 was studied by TGA preliminarily, and then was tested in a small experimental apparatus. The results show that the CO2-adsorption capability is influenced by the preparation temperature of Li4SiO4 synthesis, and it was the largest at 700 ℃. The maximum adsorption capability could achieve 34%. Besides, the adsorption capability increases as the adsorption temperature going up and longer time. When CO2 concentration was 75%, 67%, 60%, the adsorption capability could respectively reach 6.68 mmol/g, 3.37 mmol/g, 2.02 mmol/g.
Supervisor：Chinese Academy of Sciences
Sponsors by：Shanxi Institute of Coal Chemistry, Chinese Academy of Sciences Chinese Chemical Society
