Abstract: Distribution of V2O5 on activated coke (AC) can not be characterized by common techniques such as X-ray diffraction (XRD) analysis and EXAFS, etc. In this article, chemical absorption of SO2 on V2O5/ACs is used to elucidate V2O5 distribution. The aggregation of V2O5 is calculated through the amount of lattice oxygen in V2O5 responsible for SO2 adsorption and oxidation. Results show that, under the conditions used, the aggregation degree of V2O5 increases with V2O5 loading, but the number of aggregates change a little. Differences in AC′s surface area, ash, O, and N contents show little influence on V2O5 distribution.
Abstract: Chemicallooping combustion with inherent CO2 enrichment depends on highpowered oxygen carriers. Ni(NO3)2 and Al(OC3H7)3 are selected as main raw materials to prepare sol-gelderived NiO/NiAl2O4, by matching appropriate experimental parameters. The oxygen carrier with a mass content of 60% NiO, a sintering temperature of 1300℃, and a sintering time of 6h performs comparatively good physicochemical properties. The circular reductionoxidation reaction between NiO/NiAl2O4 and methane/air has been investigated with help of a thermogravimetric analyzer (TGA). X-ray diffraction (XRD), scanning electron microscope (SEM), and N2 adsorptiondesorption (BET) methods were utilized to characterize the physicochemical properties of the fresh and used oxygen carriers. The experimental results show that the sol-gelderived NiO/NiAl2O4 oxygen carriers demonstrate an extremely good recycling ability of reductionoxidation reaction. The reduction of NiO occurs in the presence of CH4, and the reduced Ni is oxidized to NiO in air. As the circulation proceeds, the reduction degree is gradually intensified and the oxidation degree is gradually alleviated. The rates of the reduction intensification and the oxidation alleviation decrease gradually, and then the reductionoxidation reactivity of the oxygen carriers increases by degrees. The sintering behavior between different particles is not observed, and the porous beehive structure of the particle is maintained after several circle reductionoxidation reactions. These experimental results prove that the solgelderived oxygen carrier NiO/NiAl2O4 is capable of being equipped by chemicallooping combustion fueled by CH4.
Abstract: Vapor heterogeneous condensation on the surfaces of PM2.5 was used to increase the removal efficiency of PM2.5 from combustion. An experimental device was set up to investigate the influence of particle initial size distribution, the amount of vapor addition, and the ratio of liquid to gas on removal efficiency. The particle size distribution and concentration at the outlet of scrubber were measured by Electrical Low Pressure Impactor (ELPI). The microstructure and major element compositions of fine particles were explored by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The results show that the physicochemical properties of fine particles from coal and oil are very different. And it has considerable influence on heterogeneous nucleation behavior. The removal efficiency of PM2.5 of coal combustion is higher than that of oil. Both number and mass removal efficiencies increase with the increase in particle size and additional amount of vapor. The removal efficiency of 81%and 72% can be achieved for coal and oil combustion of fine particles with particle diameters of 0.4μm at 0.08kg/m3 gas, respectively. Moreover, the collection efficiency can be improved with an appropriate ratio of liquid to gas.
Abstract: Coal liquefaction residue was fast pyrolyzed in a fixedbed reactor and slow pyrolyzed in thermal blance under N2 atmosphere. The influence of final temperature, residence time and particle size on char property was examined. It is found that final temperature and reside time are the dominant factors on flash pyrolysis. With the final temperature increasing, the char yields decrease and the char becomes crisper and less reactive. Less char yields and more porous char are obtained as the residence time becomes longer. At the same time, char yield reduces as the residual particle size becomes smaller in a large size range.
Abstract: Three industrial wastes including black liquor from papermaking industry, coal slag, and sludge were used as catalysts for petroleum cokeCO2 gasification. The gasification kinetics characteristics with and without catalyst were studied using a pressurized thermogravimetric analyzer (TGA). It is shown that gasification rate increases with increasing conversion and then decreases after reaching a maximal rate for noncatalytic gasification, while decreases in whole course for catalytic gasification. The proposed normal distribution function model describes well the kinetic curve for both noncatalytic and catalytic gasification. The calculated activation energy of noncatalytic petroleum cokeCO2 gasification is 197.7kJ/mol, which is in accordance with the reported data. The activities of three catalysts are contributed to the content of metal species. The black liquor in papermaking industry rich in Na species has the best activity, and its gasification rate is six times as that of noncatalytic gasification.
Abstract: Pyrolysis characteristics of oil sludge were studied by thermogravimetric analysis-Fourier transform infrared spectroscopy (TG-FTIR) and tubular electric furnace. The pyrolysis process and major influence factors like sludge property and heating rate were analyzed. The releasing behavior of noncondensed gas was also studied to understand pyrolysis mechanism. The results indicate that the pyrolysis process has five reactions including water volatilization, light oil volatilization, heavy oil pyrolysis, semicoke charring and mineral decomposition. Reaction of mineral oil focuses on 220℃～480℃. The source of sludge is important for its pyrolysis behavior. The weight loss of bottom sludge and sewage sludge is greater than that of petroleum contaminated soil. Property of oil source is less important relatively. mineral content was higher, volatile conversation rate increased; With the rising of heating rate the reaction rate increases, while volatiles conversion rate decreases. Pyrolysis mechanism includes cracking reaction of oxygenous functional groups, chain scission of linear and side chains of hydrocarbon, cyclization, aromatization and condensation reactions to dehydrogenate.
Abstract: Diesel oil (0#) was used as the reaction solvent for lipasecatalyzed esterification of high acid value waste oil to produce biodiesel; in this way, the resultant mixture could be directly used as diesel oil and the troublesome operation of distillation and reclamation of solvent was avoided. The optimum conditions for esterification of high acid value waste oil were as follow: the amount of Novozyme435 being 10% based on oil weight, initial molar ratio of methanol to oil being 2∶1, weight ratio of diesel oil to waste oil being 5∶1, shaking rate of 170r/min; the esterification conversion of fatty acid to methyl ester reached 95.10% after reaction at 50℃ for 2h and the stability of Novozyme435 was also improved obviously with diesel oil as solvent. Moreover, the diesel oil may dilute the rudimental phospholipids harmful to lipase in the waste oil slightly, though the degumming treatment of waste oil is still a key factor to determine the stability of Novozyme 435 and the feasibility of producing biodiesel from high acid value waste oil.
Abstract: The solubility parameters (including dispersion coefficient δd, polarity δp, and hydrogen bonding δh) of extraction solvents (like ketones, chlorinated hydrocarbon, ester, alcohol, and ether) and diesel oil components (n-alkanes and aromatics) were estimated by using the group contribution method. The relationship between the solubility parameters of the solvent and the extraction efficiency of nalkane from diesel oil was investigated. The results illustrated that the larger the difference between the solvent and nalkane in the solubility parameters is, the higher is the extraction ratio, for the solvents except alcohols. Nonalkane content of waxpaste removed by the solvents with a dispersion contribution (fd) of higher than twothirds was much less than that by the solvents with a lower fd.
Abstract: Through laboratory experiments with samples from Daqing and Liaohe oilfields, the effects of reservoir mineral, NiSO4 and tetrahydronaphthalene (THN) on the aquathermolysis (AT) of heavy oil were investigated. The results indicate that, in contrast with simple AT, the addition of reservoir minerals leads to lower average molecular weight, higher contents of saturated and aromatic hydrocarbon fractions and lower contents of resin and asphaltene fractions, and the viscosity reduction ratio of the two oil samples increases from 7.41% and 12.95% to 16.05% and 25.29% respectively, which means that reservoir minerals can catalyze the AT of heavy oil. With the addition of NiSO4 and THN into the reaction system, the average molecular weight of the reaction products decreases further, the contents of saturated and aromatic hydrocarbon fractions increase and the contents of resin and asphaltene fractions decrease further, the viscosity decreases greatly with a reduction ratio as high as 84.39%.
Abstract: An ionic liquid was synthesized with anhydrous aluminum chloride and amine hydrochloride with the mole ratio of 2∶1. The isomerization of n-hexane catalyzed by the ionic liquid was investigated. The results indicate that the ionic liquid can catalyze the isomerization of n-hexane, but it requires long reaction time. The influence of initiators including n-butanol, i-butene, i-butane and i-pentane on the isomerization of n-hexane was investigated. The conversion of n-hexane, the yield of liquid components and the selectivity of isoparaffins are 84.54%, 80.08% and 94.74%, respectively, when i-pentane is used as the initiator. This shows that i-pentane is a good initiator for the isomerization of n-hexane. The dosage of ipentane shows great influence on the isomerization of n-hexane, and the suitable dosage is 30%. The initiator i-pentane can greatly accelerate the rate of the isomerization of n-hexane. The reaction time can be shortened from 6h to 45min to achieve the similar reaction extent.
Abstract: The effect of benzene on the isomerization of n-hexane over Pt/Ga2O3/WO3/ZrO2 (PtGWZ) and Pd/Al2O3/ WO3/ZrO2 (PdAWZ) catalysts were investigated comparatively. The results indicate that the activities of both PtGWZ and PdAWZ catalysts for n-hexane isomerization decrease with the increase of benzene amounts in the feed. Compared with PdAWZ catalyst, PtGWZ catalyst is less influenced by benzene. The inhibiting effect of benzene on the isomerization activities of PtGWZ is reversible and the activity for n-hexane isomerization can be fully recovered when benzene containing feed is replaced by pure n-hexane. However, the inhibiting effect of benzene on n-hexane isomerization activity of PdAWZ is irreversible. For the benzene containing feed, the deactivating effect can be observed on PdAWZ catalyst, but no deactivating effect on PtGWZ catalyst can be found. This deactivating effect is due to a rapid coke formation from cyclohaxane, which formed from benzene hydrogenation on the catalysts. The reasons for the different inhibiting effects of benzene on the isomerization activities of PtGWZ and PdAWZ catalysts are discussed.
Abstract: Investigation into the temperature programmed reduction (TPR) of bulk or γ-Al2O3 supported molybdenum trioxide using nhexane as a carbon source in hydrogen was carried out. The resulting catalyst was evaluated using dibenzothiophene (DBT) as a model compound for hydrodesulfurization (HDS). The results showed that the utilization of n-hexane can lower the temperature, to fulfill carburization to some extent. For DBT HDS, however, there existed an optimal temperature at which carburization was carried out, leading to a high activity of the resulting catalyst. In these experiments, it was found that the resulting catalyst exhibited the highest DBT HDS activity if the precursor, MoO3/γ-Al2O3, with 30% theoretic loading, was carburized at 620℃ under atmospheric pressure and 0.025 mol ratio of nhexane to hydrogen in carburizing reagents.
Abstract: The photocatalytic oxidation of dibenzothiophene (DBT) in noctane (as solvent) was conducted using H2O2 as oxidant， TiO2 loaded on activated carbon as photocatalyst and 30W ultraviolet lamp as light source. The effect of calcination temperature and the amount of TiO2 loaded on activated carbon, photocatalyst amount, H2O2 amount and the radiation time on the removal ratio of DBT were investigated in detail. The results show that the TiO2/activated carbon prepared by solgel method has good catalytic activity to DBT oxidation. The optimal photocatalytic oxidation conditions of DBT are 400℃of calcination temperature， 32% of the amount of TiO2 loaded on activated carbon, 0.7g/100mL of the amount of photocatalyst and 10mL ( O/S(mol ratio)= 14) of the H2O2 amount. Under optimal conditions, the removal ratio of DBT is up to 90% by 8h radiation time. The photocatalytic oxidation of dibenzothiophene (DBT) DBT reaction is a firstorder reaction.
Abstract: A series of spherical ironbased (Fe/Mn/K) catalysts were prepared by the combination of coprecipitation and spray drying method; the influences of incorporation manner of Mn promoter on their crystallite structure, reduction and carburization behaviors and performances in FischerTropsch synthesis were investigated though H2 differential thermo gravimetric analysis (H2-DTG), CO temperatureprogrammed reduction (CO-TPR), Mossbauer spectroscopy as well as catalytic tests. The catalysts were evaluated in a slurry reactor under the industrially relevant reaction conditions of 250℃, 1.5MPa, H2/CO = 0.67 and a space velocity of 2.0L/gcat-h. The results illustrated that the addition of precipitated Mn brings on stronger Fe-Mn interaction than other incorporation manners; this may suppress the reduction and carburization of the catalyst, decrease the catalytic activity but enhance the catalytic stability. The addition of partial precipitated and binder Mn promotes the reduction and carburization of the catalyst, improves the catalytic activity but speeds up the catalyst deactivation. Compared with the precipitated Mnpromoted catalyst, the addition of partial precipitated and binder Mn can enhance the selectivity of heavy hydrocarbons and olefins and restrain the formation of oxygenates.
Abstract: The PVPstabilized AuPd/CeO2 bimetallic catalysts were prepared by CH3CH2OH(ER), CH2OHCH2OH(GR) and N2H4·H2O(HR) reductants and their catalytic performance for partial oxidation of methanol was studied. XRD, TPR, TPD were used to characterize the catalysts. Comparing the Au-Pd/CeO2(GR) and Au-Pd/CeO2(HR) catalysts, AuPd/CeO2(ER) catalyst showed higher methanol conversion, hydrogen selectivity and lower content of CO for partial oxidation of methanol reaction (POM). Au-Pd/CeO2(ER) catalyst had larger BET surface area, dispersion and CH3OH adsorption amount, stronger metalsupport interaction , more AuxPdy alloy and smaller particles, which were all advantageous to the catalytic activity for the titled reaction.
Abstract: A novel miniature platetype reactor was successfully fabricated, which combines methanol steam reforming and catalytic combustion reactions. It can be startedup fast and keeps selfsustained, i.e. without any external heating during the operating process. A number of the methanol steam reforming (MSR) tests were carried out in the reactor. The temperature distribution in the reforming and combustion chambers and the effects of temperature, space velocity and water/methanol ratio on the hydrogen production process were studied. The optimal methanol conversion of 94.85% can be attained at the temperature of 270℃, the space velocity of 870h-1, and the water/methanol ratio of 1.3. The production gas consists of 74.53% H2, 1.76% CO, and 23.71% CO2. The maximum hydrogen throughput is up to 6000mL/h, which can meet the hydrogen feed for a portable fuel cell system.
Abstract: Characterization of activated carbon has been carried out by N2, CO2 adsorption and iodine adsorption value. It is shown that both iodine adsorption value and pore structure parameters based on BET, D-R model for N2 adorption isotherms can not be used to reflect the adsorption property of CO2 in activated carbon. The D-A model results obtained from CO2 adsorption isotherms are not suitable for characterizing the adsorption of CO2 on activated carbon, either. The results of DFT model for CO2 adsorption isotherms showed that the adsorption of CO2 on activated carbon is in the ultramicropore. The micropore volumes from DFT model are consistent with CO2 adsorption isotherms. DFT model based on CO2 adsorption isotherms can be used to analyze the adsorption of CO2 perfectly.
Abstract: Many spent catalysts for the flue gas desulfurization under dry conditions can be regenerated to produce elemental sulfur with H2, which requires the tail gas recycle during the regeneration and the catalysts with dual functions for SO2 oxidation during desulfurization and released SO2 reduction during regeneration. A number of metal oxide doped V2O5/AC catalysts for flue gas SO2 removal and elemental sulfur production during H2regeneration were studied. Results show that V2O5 plays an important role in SO2 removal, while the metal oxides play important roles in elemental sulfur production. WO3, Fe2O3 and CoO additives can improve the elemental sulfur yield (ESY) and CoO has the highest activity. A catalyst with 1% V2O5 and 0.5% CoO on AC is found to be the best one, and the catalyst preparation methods used in this paper show little effect on the performance of the catalyst. The transformation of CoO to CoS2 is necessary for elemental sulfur production. It is found that the regenerated catalysts contain some CoS2 which is associated with the vanadium amount in catalyst.
Abstract: The effects of chlorides (including inorganic chloride NaCl and organic chloride PVC) on Pb emission during MSW incineration were investigated using a tubular furnace and a simulated MSW containing heavy metals. The concentrations of heavy metals were measured by ICPAES after digesting of samples including bottom ash, fly ash and flue gas according to related US EPA methods. Heavy metal species in bottom ash and fly ash were identified by X-ray diffraction technique. The spectra of elements distributed and micrographs of bottom ash and fly ash were detected by energy dispersive X-ray system and scanning electron microscope, respectively. The results indicate that the emission of Pb tends to be enhanced with the increasing of chloride content, so partitioned in fly ash. The effect mechanism of inorganic chloride NaCl and inorganic chloride PVC on Pb emission is different. NaCl tends to form PbCl2 with Pb. For PVC, besides the resultant PbCl2, PVC tends to form Pb(ClO4)2, PbCl2O4 and PbO2 with Pb. Incineration temperature and residence time are two major factors influencing the partitioning of Pb.
Abstract: The two fluid model was used to simulate a jetting fluidized bed coal gasifier with the support of CFD (Computational Fluid Dynamics) software. The modeling results for the behavior of gassolid flow and the heat and mass transfer in the fluidized bed gasifier were discussed. It can be concluded that the gassolid flow behavior greatly influences the heat and mass transfer in the fluidized bed gasifier.
Abstract: Sulfation reaction process of red mud and limestone were investigated by thermogravimetric analysis method. Phase composition of desulfurization product and calcined sample microstructure were examined by XRD, mercury intrusion porosimeter and SEM respectively. Desulfurization mechanism of red mud was discussed, which provided useful data for red mud as substitute for limestone used for coal desulfurization agents. It is shown that the possible desulphurization index of red mud is higher than that of limestone under the same condition. Calcined red mud has more middling size pores and larger specific surface areas than calcined limestone, which enhances desulfurization reaction rate. Moreover, red mud includes more ferrite and alkali metal salt compared with limestone. At low temperature they can enhances lattice defect of desulfurization agents and the diffusion ability of Ca2+ and O2-. This improves speed of surface chemical reaction and final reaction. At high temperature ferrite and alkali metal may form fused mass with dicalcium silicate together. This reduces specific surface area and porosity of red mud, thus, desulfurization activeness of red mud is weakened. Alkali earth metal carbonate may be added when red mud is used for desulfurization agents in higher temperature boiler.
Abstract: The thermal decomposition of a kind of brominted epoxy resin(BER) printed circuit boards was investigated by using TGFTIR and PyGC/MS. The mechanism of the thermal decomposition of the resin was discussed. The experimental results show that during the thermal decomposition of BER, the brominated parts are firstly decomposed with the splitting of OH—C, O—CH2, C—C (Benzene) bonds, and the pyrolysis products such as CO, acetone, bromomethane, bromophenol and 2,6-dibromophenol are produced. The decomposition of unbrominated parts is conducted at higher temperature with the splitting of OH—C， CH2—O—benzene, C—C(Benzene) bonds, and the pyrolysis products containing phenol, p-isopropylphenol, p-isopropenylacetylphenol, o-ethylphenol and p-methylphenol are made.
Abstract: Pretreatments of the viscose rayon based activated carbon fibers (ACFs) with acid (HNO3, H2SO4, HCl), alkali (NaOH) and steam were carried out to modify the surface characters of ACFs. The activities of ACFs for selective catalytic reduction (SCR) at lower temperature were tested. There is an increase in the content of functional group with oxygen on the surface of ACF and a decrease in micropore range for the ACF treated with HNO3. The new functional groups are formed for the ACF treated with H2SO4, HCl and NaOH, which can improve the activity of SCR, and an increase in micropore range for ACF treated with NaOH is found. However, the portion of mesopores increases but the catalytic activity of ACF decreases for the ACF treated with steam.
Abstract: The program Chemkin was used to investigate effect mechanism of existence patterns of sulfur on reduction of NO under poor oxygen condition. Three factors such as combustion of hydrocarbon, formation of NOx and interaction between sulfur and nitrogen were considered. The results show that reaction of HCN oxidation to NO finishes in milliseconds, whereas the reduction process of NO is gentle, finishing in seconds. SH and SN are important matters for direct reduction of NO under poor oxygen conditions. The reaction between SH and NO is intense, because concentration of SH increases after addition of SO2. As a result concentration of NO decreases. Therefore, existence patterns of sulfur can promote reduction of NO effectively under poor oxygen condition.
Supervisor：Chinese Academy of Sciences
Sponsors by：Shanxi Institute of Coal Chemistry, Chinese Academy of Sciences Chinese Chemical Society
