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Efficient removal of phosphate from aqueous solution using novel magnetic nanocomposites with Fe_3O_4@SiO_2 core and mesoporous CeO_2 shell

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Journal of Rare Earths 2017年第10期35卷 984-994页

作者：丁鸿赵燕凌段倩林王俊文张侃丁光月谢鲜梅丁传敏 College of Chemistry and Chemical Engineering Taiyuan University of Technology Department of Medical Imaging Shanxi Medical University State Key Laboratory of coal Conversion Institute of Coal Chemistry of CAS

Fe_3O_4@SiO_2 magnetic nanoparticles functionalized with mesoporous cerium oxide（Fe_3O_4@SiO_2@mCeO_2） was fabricated as a novel adsorbent to remove phosphate from water. The prepared adsorbent was characterized by X-ray diffractometry（XRD）, transmission electron microscopy（TEM）, nitrogen adsorption-desorption and vibrating sample magnetometry（VSM）, and its phosphate removal performance was investigated through the batch adsorption studies. Characterization results confirmed that mesoporous cerium oxide was successfully assembled on the surface of Fe_3O_4@SiO_2 nanoparticles, and the synthesized adsorbent possessed a typical core-shell structure with a BET surface area of 195 m^2/g, accessible mesopores of 2.6 nm, and the saturation magnetization of 21.11 emu/g. The newly developed adsorbent had an excellent performance in adsorbing phosphate, and its maximum adsorption capacity calculated from the Langmuir model was 64.07 mg/g. The adsorption was fast, and the kinetic data could be best fitted with the pseudo-second-order kinetic model. The phosphate removal decreased with the increase of solution pH（2 to 10）, while the higher ionic strength slightly promoted the phosphate adsorption. The presence of Cl~– and SO^（2–）_4 could enhance the adsorption of phosphate whereas HCO~–_ 3 had interfering effect on the phosphate adsorption. The adsorption mechanism was studied by analyzing Zeta potential and FTIR spectroscopy, and the results indicated that the replacement of the surface hydroxyl groups by phosphate ions with the formation of inner-sphere complex played a key role in the phosphate adsorption. The spent adsorbent could be quickly separated from aqueous solution with the assistance of the external magnetic field, and the adsorbed phosphate could be effectively desorbed using a 1 mol/L NaOH solution.

关键词： magnetic nanoparticles mesoporous cerium oxide phosphate removal adsorption mechanism rare earths

Mechanical Properties and Morphology of the Clay/Waterborne Polyurethane Nanocomposite

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Journal of Wuhan University of Technology(Materials Science) 2006年第4期21卷 24-27页

作者：张永成王心葵 institute of coal Chemistry Chinese Academy of Sciences Taiyuan 030001China

Stable clayl waterborne polyurethane nanocompostie dispersions were synthesized by sulfonated poly （ butylene adipate ） diol , 4,4-diphenylmethane diisocyanate , dimethyl propionic acid, 1,4-butanediol, triethyl amine and clay-water dispersion through a route named prepolymer acetone mixing progress. The reinforced mechanical properties and thermal resistance of films casting from h were examined by dynamic mechanical analyses （ DMA ）, thermogravimetrie analyses （ TGA ） and tensile tests. Furthermore, the morphology of these nanocompostie films and dispersions were observed by transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, wide-angle X-ray diffraction analyses（ WXRD ）. The experimental results reveal that the clay could be predominantly dispersed in the pristine polymer forming nanacomposties, and evidently enhanced the tensile properties and modulus of it. Addhionally, the best-reinforced effect could occur when the clay content was near 1 wt% .

关键词： polyurethane waterborne clay nanacornposties

Investigation of oxy-fuel combustion for methane and acid gas in a diffusion flame

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Chinese Journal of Chemical Engineering 2024年第1期65卷 106-116页

作者： Songling Guo Xun Tao Fan Zhou Mengyan Yu Yufan Wu Yunfei Gao Lu Ding Fuchen Wang institute of Clean coal Technology East China University of Science and TechnologyShanghai 200237China

Co-combustion of methane(CH4)and acid gas(AG)is required to sustain the temperature in Claus reaction *** this study,oxy-fuel combustion of methane and acid gas has been experimentally studied in a diffusion *** equivalence ratios(ER=1.0,1.5,2.0)and CH_(4)-addition ratios(CH_(4)/AG=0.3,0.5,0.7)were examined and the flame was interpreted by analyzing the distributions of the temperature and species concentration along central ***_(4)-AG diffusion flame could be classified into three sections namely initial reaction,oxidation and complex reaction *** oxidation of CH_(4)and H_(2)S was noted in the first section wherein H_(2)S was preferred and both were mainly proceeding decomposition and partial ***_(2)was formed at oxidation section together with obvious presence of H2 and ***,H2 and CO were inclined to be sustained under fuel rich condition in the complex reaction *** ER and increasing CH4/AG contributed to higher temperature,H_(2)S and CH_(4)oxidation and CO_(2)*** a growing trend for CH_(4)and AG to convert into H_(2),CO and SO_(2)could be *** this factor enhanced the generation of CS2 and COS in the flame inner core by interactions of CH4 and CO_(2)with sulfur *** was formed through the interactions of CO and CO_(2)with sulfur *** CS_(2)production directly relied on reaction of CH_(4)with sulfur *** concentration of COS was greater than CS_(2)since CS_(2)was probably inhibited due to the presence of H_(2).COS and CS_(2)could be consumed by further oxidation or other complex reactions.

关键词： Acid gas Methane Oxy-fuel combustion Oxidation Chemical analysis Carbon sulfides

Structural evolution of carbon aerogel microspheres by thermal treatment for high–power supercapacitors

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Journal of Energy Chemistry 2018年第2期27卷 439-446页

作者： Feng Li Lijing Xie Guohua Sun Fangyuan Su Qingqiang Kong Yufang Cao Xiangyun Guo Chengmeng Chen CAS Key Laboratory of Carbon Materials Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 Shanxi China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 07000I Shanxi China

In this work, a series of carbon aerogel microspheres（CAMs） with tailored pore structures were successfully prepared via a sol-gel method and subsequent heat-treatment at various temperatures from 600 to 1600 ℃. The effects of heat-treatment temperature（HTT） on the CAM microstructure were systematically investigated by physical and chemical characterization. The electrical conductivity increased by up to 250 S/cm and mesopores with high electrolyte accessibility developed in the CAM with increasing HTT. However, the specific surface area（SSA） decreased for HTTs from 1000 to 1600 ℃. The results show that these two factors should be finely balanced for further applications in high power *** CAMs carbonized at 1000 ℃ had the highest SSA（1454 m^2/g）, large mesoporous content（20%） and favorable conductivity（71 S/cm）. They delivered a high energy density of 38.4 Wh/kg at a power density of 0.17 kW/kg. They retained an energy density of 25.5 Wh/kg even at a high power density of 10.2 kW/kg,and a good rate capability of 84% after 10,000 cycles. This performance is superior to, or at least comparable to, those of most reported carbon materials.

关键词： Carbon aerogel microspheres Heat-treatment temperature Physical/chemical changes Conductivity Supercapacitor

Influence of Additives Ceria and Lanthana on Performance of Pd/Al/Monolith Honeycomb Catalysts

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Journal of Rare Earths 2003年第5期21卷 529-532页

作者：田东旭王浩静王心葵 Shanxi institute of coal Chemistry Chinese Academy of Sciences

The effects of ceria and lanthana additives on activity and thermal stabilization of the catalysts for CO oxidation were studied. The results show that the addition of CeO 2 clearly improves the catalytic activity, which may derive from the synergic effect between CeO 2 and PdO. The catalysts were characterized by means of temperature programmed reduction and X ray photoelectron spectroscopy (XPS) measurements. The XPS results of a slight increase in metal oxidation state reflect that the charge transfers from metal to ceria and ceria is slightly reduced, which leads to a decrease of the Ce O bond strength. Pd Ce synergism affects the reduction behavior of the catalysts. The TPR results show that the CeO 2 addition lowers the reduction temperature of PdO, while palladium facilitates the reduction of the ceria. For PdO/La 2O 3/Al 2O 3/monolith honeycomb catalysts, the aging test measurements at 1050 ℃ and the XRD results show that the formation of LaAlO 3 which neutralizes the surface alumina defects inhibits the sintering of alumina.

关键词： catalitic chemistry ceria lanthana H 2 TPR rare earths

Effect of Sulfate on an Iron Manganese Catalyst for Fischer-Tropsch Synthesis

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Journal of Natural Gas Chemistry 2007年第4期16卷 354-362页

作者： Tingzhen Li Yong Yang Zhichao Tao Haijun Wan Xia An Chenghua Zhang Hongwei Xiang Yongwang Li State Key Laboratory of coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 Shanxi China Graduate University of the Chinese Academy of Sciences Beijing 100029 China

The effect of sulfate on Fischer-Tropsch synthesis performance was investigated in a slurryphase continuously stirred tank reactor （CSTR） over a Fe-Mn catalyst. The physiochemical properties of the catalyst impregnated with different levels of sulfate were characterized by N2 physisorption, X-ray photoelectron spectroscopy （XPS）, H2 （or CO） temperature-programmed reduction （TPR）, Mossbauer spectroscopy, and CO2 temperature-programmed desorption （TPD）. The characterization results indicated that the impregnated sulfate slightly decreased the BET surface area and pore volume of the catalyst, suppressed the catalyst reduction and carburization in CO and syngas, and decreased the catalyst surface basicity. At the same time, the addition of small amounts of sulfate improved the activities of FischerTropsch synthesis （FTS） and water gas shift （WGS）, shifted the product to light hydrocarbons （C1-C11） and suppressed the formation of heavy products （C12＋）. Addition of SO4^2- to the catalyst improved the FTS activity at a sulfur loading of 0.05-0.80 g per 100 g Fe, and S-05 catalyst gave the highest CO conversion （62.3%）, and beyond this sulfur level the activity of the catalyst decreased.

关键词： Fischer-Tropsch synthesis iron-based catalyst sulfate content ferrous sulfate manganese

The Mechanical Properties of Polyurethane Elastomer Reinforced and Toughened By CaSO_4-Whisker

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Journal of Wuhan University of Technology(Materials Science) 2002年第3期17卷 50-53页

作者：刘玲 Shanxi institute of coal Chemistry Chinese Academy of Sciences Taiyuan China

CaSO 4 whisker reinforcing and toughening mechanisms for polyurethane elastomer were studied. The effects of dispersity of CaSO 4 whisker and interfacial bonding state on reinforcement and toughness were *** microanalyses showed that CaSO 4 whisker reinforcing mechanism for polyurethane elastomer mainly was load transferring and its toughening mechanism involved crack deflection and whisker *** results indicated that composites with 5%-10% CaSO 4 whisker exhibited the best mechanical properties. Good bonding interface was formed between whisker and matrix after the surface of CaSO 4 whisker was treated by silane coupling *** fairly improved strength and toughness are attributed to the better interfacial bonding state.

关键词： whiskers polyurethane elastomer reinforcement and toughness composite

A GENERALIZED EQUATION FOR HETP IN COLUMN CHROMATOGRAPHY

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Science China Chemistry 1987年第6期30卷 572-581页

作者：陈诵英彭少逸 Taiyuan The institute of coal Chemistry Academia Sinica

Based on an axial dispersion model, a generalized equation for HETP in column chromatography ispresented. From this equation, Van Deemter’s equation for packed column and Golay’s for capillary col-umn can be derived under simplified conditions. The generalized equation can be used to obtain variousempirical equations for HETP and gives physical significance to the empirical constants in them. It isadaptable to all column chromatography including packed and capillary columns as well as gas andliguid chromatography.

关键词： A GENERALIZED EQUATION FOR HETP IN COLUMN CHROMATOGRAPHY

Paleo-fires and Atmospheric Oxygen Levels in the Latest Permian:Evidence from Maceral Compositions of coals in Eastern Yunnan,Southern China

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Acta Geologica Sinica(English Edition) 2012年第4期86卷 949-962页

作者： SHAO Longyi WANG Hao YU Xiaohui LU Jing ZHANG Mingquan State Key Laboratory of coal Resources and Safe Mining and School of Geosciences and Survey EngineeringChina University of Mining and Technology institute of Disaster Prevention coal Geology and Prospecting institute of Yunnan Province

Inertinite maceral compositions of the Late Permian coals from three sections in the terrestrial and paralic settings of eastern Yunnan are analyzed in order to reveal the paleo-fire events and the atmospheric oxygen levels in the latest Permian. Although the macerals in the studied sections are generally dominated by vitrinite, the inertinite group makes up a considerable proportion. Its content increases upward from the beginning of the Late Permian to the coal seam near the Permian- Triassic boundary. Based on the microscopic features and the prevailing theory that inertinite is largely a by-product of paleo-fires, we suggest that the increasing upward trend of the inertinite abundance in the latest Permian could imply that the Late Permian peatland had suffered from frequent wildfires. Since ignition and burning depend on sufficient oxygen, a model-based calculation suggests that the 02 levels near the Wuchiapingian/Changhsingian boundary and the Permian-Triassic boundary are 27% and 28% respectively. This output adds supports to other discoveries made in the temporal marine and terrestrial sediments, and challenges the theories advocating hypoxia as a mechanism for the PermianTriassic boundary crisis.

关键词： coal maceral inertinite paleo-atmospheric oxygen level wildfire Permian-Triassic boundary