Abstract: The changes of apparent viscosity of coal-oil slurries with temperature during direct coal liquefaction were studied. Several factors influencing the viscosity of coal slurries were discussed, which include solvent properties, coal concentrations, moisture content, macerals of coal, shear rate, temperature, swelling behavior, etc. The apparent viscosity of coal slurries was measured using a high-temperature viscometer. The results show that the solvent property is the main influencing factor at low temperature, and the apparent viscosity decreases with increasing temperature. Solvent properties and swelling behavior work together for the viscosity of slurries at medium temperature, leaving the apparent viscosity invariable. Swelling behavior becomes the main influencing factor at high temperature, and viscosity of slurries increases with increasing temperature.
Abstract: Removal and transformation behavior of chlorine in two Chinese bituminous coals (WJP and HYS coal) during sub-critical water treatment were studied in a semi-continuous apparatus. The influence of temperature and pressure on the removal of chlorine was examined; and chemical extraction was also done to determine the occurrence mode of chlorine in raw coal and its residues. The results show that the removal of chlorine in two coals all increases with increasing temperature; at 410℃, 15MPa, 60min and water flow rate of 580mL/h, the removal of chlorine is 84.6% and 72.4% for WJP and HYS coal, respectively. The maximum removal of chlorine from WJP coal, 79.8%, is obtained under 15MPa. Chlorine in HYS coal is mainly organically associated, among which 23.6% is bonded to organic cations by ion exchangeable mechanism and 76.4% is covalently-bond organic chlorine; while for WJP coal, that is 39% and 52.9%, respectively, and the other 8% is associated with inorganic matters. During sub-critical water treatment, chlorine bound to organic cations by ion exchangeable mechanism is more easily volatilized than covalently-bond organic chlorine; and the chlorine associated with organic matters will be firstly turned into inorganic form, and then released from the coal.
Abstract: The effect of coal, char, and volatiles (obtained from coal under different conditions) on NO reduction behavior has been investigated. The results show that original coal has an ability to reduce NO emission, and its efficiency depends on coal type and minerals within it. Atmosphere and temperature for char-making process influence the behavior of chars in reducing NO emission. Oxygen in charmaking atmosphere can change the action of chars depending on coal types. The volatiles released from high-volatile coal have a greater capacity for NO reduction, and the volatiles obtained in N2 have a greater capacity for NO reduction than that obtained in CO2, whereas the minerals in coal can break this trend. O2 in volatile-making atmosphere also affects NO reduction of volatiles depending on coal types. For Tongchuan(TC), it decreases with the increase in amount of O2 added. For Sanxie(SX), Shenmu(SM), and Jiaozuo(JZ), the best NO reduction efficiency appears when the amount of O2 added is 3%.
Abstract: To investigate the coal black liquor slurry′s ash deposition mechanism, a new method was proposed by contrast with coal water slurry. Ash particles were extracted from different locations of pilot boiler along the flue gas, in combination with sampling ash residue deposited on fire walls of the same distance from burner. The migrating tendency and deposition characteristics of main mineral elements along the flue gas were investigated in detail. In addition, XRD and SEM were carried out for coal water slurry and coal black liquor slurry′s ash deposit to get validation from microscopic view. The results indicate that the principal mineral elements causing ash deposition of coal black liquor slurry are sodium, silicon and aluminum. The ash deposit is composed of some phases at low fusing temperature, such as thenardite and nepheline. The minor factor is the migration and deposition of Fe, which is different from coal water slurry and coal.
Abstract: Thermal behaviors of commercial diesel oil 0# and pyrolysis oil obtained from co-pyrolysis of biomass and waste tyre blend (with or without catalysts) were investigated by thermogravimetric analysis (TG-DTG). Through linear regression, the results illustrated that for pyrolysis oils the thermal kinetic follows the formula dα/dt=Ae-△vapH/RT(1-α)2 and for diesel oil it follows the formula dα/dt=1.5Ae-△vapH/RT(1-α)2/3\[1-(1-α)1/3\]-1. The evaporation heats calculated were 37.46kJ·mol-1 for SBAcatalyzed pyrolysis oil, 30.60kJ·mol-1 for MCM-41-catalyzed pyrolysis oil, 41.27kJ·mol-1 for pyrolysis oil without using any catalyst, and 55.50kJ·mol-1 for diesel oil 0#; these values were close to those reported in the literature. The existence of SBA-15 and MCM-41 as catalysts in the pyrolysis can reduce high fractions of the resultant pyrolysis oil; SBA-15 performed better than MCM-41 in reducing high fractions.
Abstract: Reducing formation of gaseous species, which contain chlorine, potassium and sodium, can effectively abate deposit formation, slagging, corrosion and harmful pollutant emission during thermal conversion of biomass fuels. The occurrence modes, transformation routines and release characteristics of those species, especial gaseous species have been investigated by thermodynamical equilibrium analysis technique for 5 biomass fuels, such as straw, bark, woodchips, waste wood and olive residues from 400K~1600K during pyrolysis and gasification with excess air coefficient as 0.4 and 0.8. The calculation results show that chlorine element exists as species of KCl(s), HCl(g), KCl(g), (KCl)2(g) and NaCl(g) for 5 biomass fuels during pyrolysis and gasification. The solid chlorinecontained species will be gradually transformed into gaseous when reaction temperature is higher than 800K~1000K. Alkali metal elements, potassium and sodiumin biomass fuels will be released as gaseous species above 900K. A little KCN(g) and NaCN(g) are transformed during pyrolysis. The amount of gaseous species KCl(g), K(g) and Na(g) will decrease and transform into NaCl(g), KOH(g) and NaOH(g) above 1000K during gasification. The optimum gasification temperatures for the lowest gaseous release of species containing chlorine and alkali metal elements are 800K and 900K, respectively. Hence, developing mildtemperature gasification technology is an alternative to abate the common problems occurred in biomass gasification reactors.
Abstract: The pyrolysis process of printed circuit boards (PCB) under different temperatures and with different molten salts loading were studied with a vertical fixed bed reactor. The liquid products and solid products were analyzed. The result shows that the binary eutectic salts can decrease the liquid product yield. Consequently, the carbon conversion rate from PCB to gas products increases greatly. Without binary eutectic salts at 900℃ the liquid yield is 28.29%, and the carbon conversion rate from PCB to gas products is 35.94%. While at 700℃, with 71% Na2CO3-29%K2CO3, the liquid yield is 22.34%, and the carbon conversion rate from PCB to gas products increases to 40.76%. When changing the molten material to 8.3% Na2CO3-91.7%NaOH, the liquid yield decreases to 6.88%, and the carbon conversion rate to gas phase reaches 59.36%. The ultimate analysis result shows that carbon in the solid products decreases while adding eutectic salts, and the H/C ratios of liquid products are between 1.12 and 1.20.
Abstract: Dagang vacuum residue was separated into four fractions (saturates, aromatics, resins, and asphaltenes, known as SARA) by chromatography. The features of molecular structure of aromatics, resins and asphaltenes were investigated by ruthenium-ion-catalyzed oxidation (RICO), where involatile acid products were methylated with excess diazomethaneether and volatile acids were esterified with phenacyl bromide. Based on GC-MS and GC analysis of these esters, homologous series of n-alkanoic acids (C4~33), α,ω-di-n-alkanoic acids (C3~24) and benzenepolycarboxylic acids were determined. The results indicate that the number of n-alkyl groups and polymethylenes connected to aromatic carbons decreases with an increase of the substituent chain length; it is characterized by an even-to-odd carbon number preference. Asphaltenes have relatively more short (C16) alkyl chains attached to aromatic carbons than resins and aromatics. Benzenedi through hexacarboxylic acids occurred in the RICO products prove the presence of polycyclic aromatic structure and can give a sight on the major mode of aromatic condensations in the fraction sample. The aromatic nuclear in asphaltenes have more peri-condensation structure units than that in aromatics. Cata-condensation modes are more abundant in aromatics.
Abstract: The effects of the carrier carbon black on the interior hydrogentransferring reactions of residual oil were studied in a miniature batch reactor. The results indicated that carbon black could promote the hydrogen transfer from tetralin to anthracene. Fe/carbon black and Ni/carbon black catalysts were prepared using equal volume impregnation method and characterized by X-ray diffraction and scanning electron microscope. The results showed that metal sulfides were attached on the surface of carbon black. The average diameter of metal sulfide crystals was about 1μm. The thermal reactions of Karamay residual oil with carbon black, Fe/carbon black, or Ni/carbon black catalyst were carried out in a batch reactor in hydrogen atmosphere to investigate their effects which then were compared with those of traditional water-soluble dispersed catalysts. The reaction temperature was 430℃ and the catalyst content was 1%. It was found that on coke formation restricting, water-washed catalyst was better than unwashed catalyst, Ni/carbon black was better than Fe/carbon black, and Fe/carbon black was better than water-soluble dispersed catalyst. The fraction distribution analysis of products showed that Fe/carbon black could restrict the cracking and condensation of residue.
Abstract: This study focused on the thermal reaction of saturate and aromatics components of Karamay atmospheric residue (KLAR) and Liaohe vacuum residue (LHVR). The reactions were carried out in a micro autoclave with dispersed-phase catalyst under hydrogen atmosphere, and then the thermal reaction kinetic parameters were calculated. Saturate and aromatics were mainly cracked into naphtha and diesel oil fraction without toluene insoluble(TI) during thermal reaction, and a considerable part of aromatics condensed into resin, and further asphaltene. At same reaction conditions, the yields of cracking products and condensation products between KLAR-saturate and LHVR-saturate were not different, but the yields of the cracking products of aromatics in KLVR was slightly higher than that of LHVR, and the yields of the condensation products of aromatics in KLVR was a little lower than that of LHAR.
Abstract: Effects of catalyst microactivity, different distillates, catalyst to oil weight ratio, reaction temperature, and reaction time on coke formation and olefins conversion were studied in FCC naphtha olefin reformulation using a microreactor-GC on-stream analysis system and a continuous pilot riser-type FCC unit. The results showed that the formation of coke deposition and the olefins conversion took place in the transient time of the oil and the catalyst mixing and increased with the catalyst microactivity, reactants activity catalyst to oil weight ratio and reaction temperature. In the long reaction time after the oil and the catalyst mixing, the formation of coke deposition and the olefins conversion were very slow and small, and the ratio of the loss to the olefin conversion decreased, so it was favorable to increase the olefins conversion through the longer reaction time. The optimal condition for FCC naphtha olefin reformulation is reaction temperature at 390℃～440℃, catalyst to oil weight ratio 6, catalyst microactivity from 61 to 65, long reaction time, and light distillates feedstock.
Abstract: Transformation of the probe molecular ethanol over the selected isomerization catalyst supports, which were prepared from Alumina, ZSM-5 and SAPO-11 powders, was investigated at different reaction temperatures. Combined with the results of acidity data by NH3-TPD, and the results of longchain C14~24 hydrocarbon hydroisomerization, the relationships among the acidity, ethanol conversion as well as the hydroisomerization performance were investigated. It was shown that neither the ethanol conversion nor the hydroisomerization could correlate with acidity. However, a good relationship between ethanol conversion and hydroisomerization was observed. When a support presented low ethylene selectivity and inferior stability during ethanol conversion, the corresponding hydroisomerization catalyst had bad performance. While a support shown stable activity and high ethylene selectivity for ethanol conversion, a hydroisomerization catalyst with better stability and high isomerization selectivity might be obtained after loading precious metal onto the support. After detailed analysis of these data, we found that it was necessary to discriminate between acidity and acidic property. Acidity includes the acid amount, acid distribution as well as acidic strength, while acidic property, temporally named as acid function, is the acidic functional behavior during a reaction. The former can be characterized by traditional method, but the later can only be probed by a catalytic transformation. The obtained data strongly suggests that it is possible to characterize the acid function of hydroisomerization catalyst by a model reaction of ethanol conversion. The model reaction using ethanol as probe molecule could be used to characterize the acid function of a support, and thus provide useful instructions in selecting hydroisomerization catalyst supports.
Abstract: A series of Pd/SiO2 and Pd/CexZr1-xO2/SiO2（x=0.0~1.0） catalysts with Pd loading from 0.1% to 1.0% were prepared by impregnation and characterized using X-ray powder diffraction and H2temperatureprogrammed reduction. Their performance in catalytic methane combustion was evaluated in a conventional quartz reactor. The effects of CeO2 and CeZrO2 solid solutions on the performance of Pd/SiO2 were investigated. The results indicated that Pd/SiO2 exhibit good catalytic activity in methane combustion, and the addition of CexZr1-xO2 can further markedly enhance its catalytic activity. CexZr1-xO2 can promote the dispersion and reducibility of PdO in Pd/CexZr1-xO2/SiO2. The molar ratio of Ce to Zr in CexZr1-xO2 plays an important role on the catalytic activity of Pd/CexZr1-xO2/SiO2.
Abstract: Two spherical iron-based catalysts (Fe/Cu/K/SiO2 and Fe/Cu/K/Al2O3) were prepared by the combination of coprecipitation and spray drying method for the application of slurry Fischer-Tropsch synthesis (FTS). The effects of SiO2 and Al2O3 on the reduction and the carburization behaviors of iron-based catalysts were studied using temperature-programmed desorption (TPD) in H2 and CO, isothermal reduction in syngas, and Mssbauer-effect spectroscopy (MES). The results indicate that SiO2 suppresses the H2 adsorption, facilitates the CO adsorption, and the carburization as compared with Al2O3. The FTS performances of the catalysts were evaluated in a slurry reactor under the industrial relevant reaction conditions of 260℃, 1.5MPa, H2/CO = 0.67, and a space velocity of 2000h-1. This indicates that SiO2-supported catalyst has higher FTS activity, higher water-gas shift reaction (WGS) reactivity, and higher selectivities to heavy hydrocarbons. Furthermore, the run stability of Al2O3 supported, iron-based catalyst is better than SiO2 supported catalyst.
Abstract: A series of alumina supported Ni, Mo-Ni and W-Ni catalysts were prepared by co-impregnation and the structure and nickel species were characterized by XRD, TPR and XPS. The effect of additive Mo(W) on catalyst activity for the hydrogenation of olefins in the fraction (boiling spread: 70℃～350℃) was studied. TPR characterization reveals the addition of additives shifts the high-temperature reduced peak to higher temperature but the low-temperature reduced peak to lower one. For the decrease of deoxidizing temperature, the effect of Mo is better than that of W. XRD measurements show that Mo and W increase the dispersion of NiO on the supports in the order of Mo>W. XPS analyse reveals the ratio of surface NiAl2O4 increases due to the presence of Mo and W. The shift of Ni2p3/2 peak indicates a stronger interaction between the NiO and γ-Al2O3 support.
Abstract: Single crystal MTN has been synthesized by vapor phase transport route (VPT) using n-propylamine as a new template. The synthesis conditions of single crystal MTN including compositions of reaction mixture, crystallization temperature, time, etc. were investigated. The synthesized samples were characterized by XRD, FT-IR and SEM. The experimental results showed that MTN could be well synthesized at the following conditions: crystallization temperature 453K~493K, crystallization time 15d, chemical compositions of gels and liquid reaction mixtures (0.5~1.0) NH4F-SiO2-6.7H2O, n-propylamine/(n-propylamine+H2O) 16.7%~100% (mol ratio) respectively. The increase in the relative crystallinity of MTN was in proportion to the increase in molar percent of n-propylamine, mole ratio of NH4F/ SiO2, crystallization temperature respectively. The particle size of the synthesized single crystal MTN was up to 250μm.
Abstract: N,N’-Bis(salicylidene)ethylenediiminocobalt (Cosalen) was encapsulated into the supercage of microporous NaY zeolite via “ship-in-a-bottle” technique, which was compared with the impregnated Cosalen complex immobilized on the outer surface of the zeolite to prove the encapsulation. The samples were characterized by AAS, FT-IR, UV-Vis, XRD, TG-DTA and SEM techniques. The oxidation of cyclohexane with oxygen was chosen to evaluate the catalytic performance of the encapsulated complex. The effects of catalyst usage, solvent and initial oxygen pressure on the oxidation reaction were investigated. The encapsulated complex Cosalen/Y(SB) exhibited high catalytic activity for cyclohexane oxidation and high selectivity to cyclohexanol, cyclohexanone and adipic acid in the CH3CN solution without adding any inducing agents, which suggested that the catalyst is potential for the oxidization of cyclohexane into adipic acid. Moreover, the catalyst exhibited excellent stability and could be reused without obvious loss of the active components.
Abstract: The effects of pH value of liquid feed as well as the presence of monomethyl ether (MME), ethyl thiol and rust in the feed on the catalytic performance of TS-1 in propene epoxidation were investigated, where the epoxidation was carried out in a continuous fixed-bed reactor and gaseous propene was pre-mixed with dilute solution of hydrogen peroxide in methanol. It was shown that the presence of MME in feed has no impact on the catalytic performance of TS-1. The addition of ethyl thiol in the feed exhibits little effect on the catalytic activity, but may cause a decrease in propylene oxide (PO) selectivity. The pH value of liquid feed influences the catalytic performance significantly; an optimum pH value is about 7. The rust in the feed may block the pores of TS-1 and then cause a partial deactivation. With a liquid feed pH value of 7 (adjusted with 0.1mol/L ammonia water), the catalyst TS-1 exhibits excellent stability at 55℃ and 0.7MPa; both H2O2 conversion and PO selectivity exceeded 90% in a 130h catalytic test.
Abstract: Copper(II) carboxymethylcellulose was prepared with sodium carboxymethylcellulose and copper sulphate in aqueous solution. Sweetening properties of copper (II) carboxymethylcellulose in liquid hydrocarbon was studied using petroleum ether containing 96×10-6 n-pentanethiol and 16×１０-6 thiophene as a model solution. Mercaptan in the model solution could be cleaned out at 24.0h-1 space velocity at room temperature. Sweeten capacity of copper (II) carboxymethylcellulose is 925mL/g for the model solution or 1.86mmol/g for mercaptan. Copper (I) that reduced from copper(II) was found in saturated cuprum carboxymethylcellulose material by XPS. Dipentyl disulfide, the oxidation product of n-pentanethiol, was detected in the model solution after sweetening by GC-PFPD. The sweetening mechanism of copper (II) carboxymethylcellulose was confirmed as an oxidation-reduction process.
Abstract: The reactivity of Zn-Cu-Mn and ZCM composite oxides prepared respectively by Co-precipitation and mechanically mixing method were investigated and compared with that of ZnO, CuO and MnO2 . Composition and structure of desulfurizer were studied by using XRD, and the sulfur compound in gas was analyzed by using FPD(flame photometric detector). The experimental results show that Zn-Cu-Mn desulfurizer possesses higher sulfidation reactivity in the temperature range of 250℃～350℃, and the optimum sulfidation temperature is 300℃. The desulfurizer has higher breakthrough sulfur capcity at the space velocity of 7799h-1. It is found that the reactivity of Zn-Cu-Mn desulfurizer is higher than that of pure ZnO when the samples are calcined at 400℃. With the calcination temperature increasing, surface area and reactivity of Zn-Cu-Mn desulfurizer reduce gradually, at the same time, spinel CuMn2O4 appears. Compared with the reactivity of Zn-Cu-Mn desulfurizer and ZnO, the reactivity of ZCM desulfurizer is lower. When the ZCM desulfurizer is calcined at about 550℃, MnO2 is reduced to Mn2O3. But the Mn2O3 will disappear and CuMn2O4 will appear when the ZCM desulfurizer is calcined at 750℃.
Abstract: Gallium atoms have been introduced into the framework of Y zeolite by treating zeolites with an aqueous solution of ammonium hexafluoro gallate. At ambient conditions and space velocity of 7.2h-1, desulfurization of various model fuel containing about 500×10-6 sulfur was studied over the modified Y zeolite (\[Ga\]AlY). The adsorption capacit of the adsorbent for the sulfur from tetrahydrothiophene (THT), 4,6dimethyldibenzothiophene (4,6DMDBT), 4methyldibenzothiophene (4MDBT), and dibenzothiophene (DBT) are 17.4×10-3, 14.5×10-3, 5.8×10-3 and 16.9×10-3 respectively. The charge on S atom of THT, 4,6DMD BT，4MDBT, and DBT, calculated by density functional theory (DFT) method, are -0.298, -0.214, -0.188 and -0.211 respectively. Implying that the electron density on S atom decrease in the order THT﹥4,6DMDBT≈DBT﹥4MDBT which agrees with the order of the sulfur adsorption capacity. Only one third Al atoms could be substituted by Ga due to the different position of Al atoms in the NH4Y. The adsorption capacity of adsorbent for the sulfur from thiophene is 7.7×10-3. The regenerated \[Ga\]AlY recovered 85% original capacity and the adsorption capacity of adsorben is 6.5×10-3.
Abstract: The removal of sulfur and changes of sulfur forms in Oman vacuum residue by hydrotreating were investigated on a pilot plant. The results illustrated that the content of total sulfur in hydrotreated residue reduced gradually with the hydrotreating. Over 80% of total sulfur in the residue can be removed at three temperatures (T-5℃, T℃, T+5℃), although a higher temperature can enhance the desulfurization effect. The residue fractions of aromatic, resin, asphaltene and saturate contain about 60%, 32%, 8% and 1% of total sulfur, respectively; however, the sulfur content in each fraction is in the order of asphaltene>resin>aromatic>saturate. The sulfidic sulfur content in the residue fraction decreased and the thiophenic sulfur content increased with the heaviness of residue fraction. Sulfur forms exhibit influence on the hydrodesulfurization effect; the removal of sulfidic sulfur is much easier than that of thiophenic sulfur. The residue fractions are also different in the desulphurization effect, depending on their molecular size and structure; the sulfur removal ratio of saturate and aromatic is higher than that of resin and asphaltene.
Abstract: Advanced reburning (AR) is one of the novel NOx control technologies. Some primary parameters of AR have been investigated by the experiments, NOx reduction performance of two fuels is analyzed contrastively. Results show that the NO removal efficiency increases quickly with the molar ratio of gas to NO and the residence time (within 0.34s) during reburning process when the temperature is 1050℃.There exists an optimum reburning stoichiometric ratio (0.7～0.8) and a molar ratio of NH3/NO (2.0) for AR process. The optimum ratio of natural gas/NO is 3.63 at the temperature of 1200℃. The optimum reburning temperatures of natural gas and liquefied petroleum gas are about 1250℃ and 1050℃, respectively. When the residence time exceeds 0.34s, the NO reduction efficiency of advanced natural gas reburning rises slowly, but that of advanced liquefied petroleum gas reburning increases rapidly.
Abstract: As an endothermic hydrocarbon fuel, pentacyclo[6.3.1.02,7.03,5.09,11]dodecane has been synthesized from dicyclopentadiene catalyzed by Zn(Cu). Effects of catalyst ingredients, catalyst amount, temperature on yield of titled compound were investigated. The optimal conditions were: 15℃, n(DCPD)∶n(Zn(Cu))∶n(CH2I2)=1∶4∶8. Under the above conditions the conversion of dicyclopentadiene was 99.7% and the yield of pentacyclodocane reached 91.5%.
Supervisor：Chinese Academy of Sciences
Sponsors by：Shanxi Institute of Coal Chemistry, Chinese Academy of Sciences Chinese Chemical Society
