高温固硫矿物3CaO·3A12O3·CaSO4的热力学数据的计算与验证

Calcium sulfoaluminate,3CaO·3Al2O3·CaSO4,has been widely recognized in the realms of high-temperature combustion and cement chemistry.However,the lack of relevant thermodynamic data limits the progress of its research and development.Through comparative calculations using several different approaches,we obtain the thermochemical properties of 3CaO·3Al2O3·CaSO4 in this work,such as its standard formation enthalpy,Gibbs free en- ergy of formation,entropy,and molar heat capacity.With these fundamental data,thermodynamic calculations become possible for reactions involving this mineral.It is found that some reactions proposed in literature to generate this mineral may not proceed thermodynamically.     

Microstructures and Corrosion Resistance of Al2O3—C Based Refractories to the Melts Containing Titania

The corrosion resisance of the Al2O3-C based refrac-tories in melts containing titania has been studied by quasi-station immersion and rotary immersionThe corrosion rate is decreased with the addition of graphite carbon and ZrO2 in the refractories.The corrosion mehanism of Al2O3-C refractories is the oxidization of graphite carbon by the oxides of the melts and the formation of deteriorate layer,For the Al2O3-C-ZrO2 refractories,the corrosion behavior is due to the interaction between melts and refrac-tories,The new compounds of FeO.SiO2,SiZrO4,Feo.3CaO,2CaO.SiO2 and CaO.SiO2 are formed in the deteriorate layer.     

钛酸酯偶联剂NDZ-3与3（CaO·A12O3）·CaSO4界面的XPS研究

借助X射线光电子能谱(XPS)定量地研究了钛酸酯偶联剂NDZ-3和3(CaO*Al2O3)*CaSO4 界面结合情况.结果表明:钛酸酯偶联剂NDZ-3的烷氧基与3(CaO*Al2O3)*CaSO4表面羟基产生化学反应,生成(Ti-O-M)[M=Al, Ca]化学键,这样钛酸酯偶联剂NDZ-3在3(CaO*Al2O3)*CaSO4表面形成偶联剂单分子层,使3(CaO*Al2O3)*CaSO4得到改性,因而改善了它与有机聚合物亲和性.     

矿物3CaO·3Al2O3·BaSO4 高温稳定性研究

矿物3CaO·3Al2O3·BaSO4是一种新型胶凝矿物, 而关于其高温稳定性的研究却有多种结论.本工作综合运用IR, TG-DT A,EPMA,XRD和QXDA等多种测试方法, 系统研究了3CaO·3Al2O3·BaSO4 的高温稳定性问题.研究表明, 在温度低于1 350 ℃的条件下, 矿物3CaO·3Al2O3·BaSO4的晶相结构稳定; 而温度高于1 360 ℃时, 3CaO·3Al2O3·BaSO 4发生分解并形成新的晶相.3CaO·3Al2O3·BaSO4的分解方程式可表述为: 3CaO·3Al2O3·BaSO4→CaO·Al2O3+12CaO·7Al2O3+Ba O·Al2O3+SO2↑+O2↑鉴于矿物BaO·Al2O3的形成机理与该问题紧密相关, 本文也讨论了BaO·Al2 O3的形成机理.BaO·Al2O3的形成机理有两种:温度低于1 350 ℃时, BaO·Al2O 3由原料组分发生反应而形成的; 而温度大于1 360 ℃时, 该矿物是由3CaO·3Al2O 3·BaSO4分解形成的.     

Corrosion Resistance of AI2O3-C Materials to Oolitic-hematite Reduction Melt

Al2O3- C specimens were prepared using fused corundum and flake graphite as starting materials,SiC as antioxidant,and phenolic resin as binder to research their corrosion resistance to oolitic-hematite reduction melt. The tests of slag penetration and corrosion were carried out by static crucible method. The corrosion resistance was presented by the corrosion area and penetration depth. The corroded specimens were investigated by XRD,SEM and EDS. The results show that:(1) the corrosion resistance of Al2O3- C materials to oolitic-hematite reduction melt is improved obviously by the addition of SiC;(2) with the rising of reduction temperature and the prolonging of reduction duration,the corrosion area and penetration depth both increase rapidly;(3) the corrosion mechanism of the oolitic-hematite reduction melt can be described as that the melt reacts with Al2O3- C materials forming some low melting compounds such as CaO·Al2O3·2SiO2,CaO·2Al2O3and Fe2SiO4.     

纳米固体超强酸SO2-4/Fe2O3的催化性能

In order to minimize the pollution of ferrous sulfate, a by-product of titanium dioxide, and increase the yield of synthetic ester, the SO4^2-/Fe2O3 nanosolid superacid has been produced by chemical precipitation and its micrographs was determined by SEM. The effect of preparation conditions of SO4^2-/Fe2O3 nanosolid superacid on catalysis synthesis butyl acetate and synthesis conditions of butyl acetate were studied. From experimental data, as compared with liquid acid, SO4^2-/Fe2O3 nanosolid superacid showed higher catalytic performance in catalytic synthesis of butyl acetate, and the yield of butyl acetate was obviously increased in the same reaction time.     

高Al_(13)含量聚合氯化铝制备γ-Al_2O_3及表征(英文)

In this paper a polyaluminum chloride solution with high Al13 content was prepared and used as raw material for preparation ofγ-Al2O3.The texture and crystalline phase of the prepared alumina samples were characterized by energy dispersive X-ray spectroscopy(EDX) ,X-ray diffraction,transmission electron microscope(TEM) and nuclear magnetic resonance(NMR) analyses.The effects of alkaline solution and calcination temperature were investigated.The results showed that alkaline solution including NH3·H2O and NaOH had little effect on the alumina sample formation.The impurities of NH4Cl and NaCl in solution can be removed through repeated washing by EDX analysis.Calcination temperature had a significant effect on alumina crystal phase.The alumina sample can transform completely toγ-Al2O3 in the subsequent heating from 600°C to 800°C.It is very interesting that Al13 can be existed inγ-Al2O3 phase even after calcinations.The results indicate that polyaluminum chloride with high Al13 content is an effective material to prepareγ-Al2O3.     

Synthesis of high purity Li_2CO_3 and MgCO_3·3H_2O in a homogeneous-like organic phase

Herein, three kinds of Li_2CO_3 and two kinds of MgCO_3·3H_2O crystals are easily synthesized in a homogeneouslike organic phase. The morphology and size of synthesized crystals are controllable and adjustable in the single organic phase, with the morphology of Li_2CO_3 ranging from micro-flaky, flower to nanobranch, MgCO_3·3H_2O ranging from nanosphere to nanorod. Compared with coupled reaction and solvent extraction process, of which the crystallization process occurred in the interface of two phase, our proposed method made it possible that the crystallization process occurred in the single organic phase, which resulted in better crystal morphology.Moreover, the formation mechanism of different crystal morphologies is discussed, the results showed that the crystals in micron size and nano size are involved in two crystallization mechanism, the micron particles in the form of flake and flower-like is a typical radial growth, which means that the growth occurs by diffusion around a nucleus as starting point, while the reaction model for small particles should be similar to a water-in-oil structure. As the reaction carried out, the crystal should be restricted in a constrained organic structure.     

甲烷/空气射流燃烧中氮氧化物生成模型的研究

With the development of reaction kinetics and transfer science, the modeling of NOx formation plays more and more important roles in the protection of environment and the design of combustion reactors; in this case, turbu-lence-chemistry model and NOx formation model are the two most important aspects. For thermal NOx mechanism, this article studied the CH4/air system and applied a set of latest NO formation rate constants published at the Leed University which replaced the original model code in FLUENT to increase its precision on prediction of NO concentration. The realizable k-ε model, Reynold Stress model and standard k-ε model were also investigated to predict the turbulent combustion reaction, which indicated that the simulation results of velocities, temperatures and concentrations of combustion productions by the standard k-ε model were in good accordance with the experimental data. With the application of the simulation results to the experimental data to fit some important kinetic parameters in the equation of O atom model and revision of the equation later, this article obtained a new NO formation rate model. It has been proved that the prediction of the developed model coincides well with the measurements.     

由二元亚系的数据预测混合电解质水溶液的活度系数

The simple equation relating the activity coefficient of each solute in mixed electrolyte solution to its value in binary solutions under isopiestic equilibrium was tested by comparison with the experimental data for the 18 electrolyte solutions consisting of 1：1, 1：2, and 1：3 electrolytes. The isopiestic measurements were made on the quaternary system BaCl2-NH4Br-NaI-H2O and its ternary subsystems NaI-NH4Br-H2O, NaI-BaCl2-H2O, and NH4Br-BaCl2-H2O at 298.15K. The results were used to test the applicability of the Zdanovskii＇s rule to the mixed electrolyte solutions which contain no common ions, and the agreement is excellent. The activity coefficients of the solutes in the above quaternary and ternary systems calculated from the above-mentioned simple equation are in good agreement with the Pitzer＇s equation.     

Synthesis of Al_2OC Compound by Carbothermal Reduction Process with Boron Oxide Additive

The synthesis method of Al2OC by adding B2O3 was studied to modulate the traditional synthesis process.The mixtures of active carbon,alumina and boron oxide with different carbon contents were heated at 1 700 ℃ for 2 h in flowing argon atmosphere to get the Al2OC product.The results indicate that the addition of B203 promotes the formation of Al2OC,which is dependent on the addition of B2 O3,and the Al2 OC content in the products increases with the increase of carbon.By systematically exploring the ratio of active carbon,alumina and boron oxide,the best formulation and the corresponding reaction mechanism were determined.     

氧化物对3CaO·3Al2O3·CaSO4形成的影响

借助XRD测试手段研究了Al2O3、SiO2、Fe2O3以及MgO几种生料中常见氧化物对高温固硫物相3CaO·3Al2O3·CaSO4形成的影响.结果表明,改变Al2O3的含量,不会对3CaO·3Al2O3·CaSO4的形成产生明显影响;Fe2O3及MgO的存在能降低3CaO·3Al2O3·CaSO4的形成温度,但也使其分解温度提前;SiO2的大量存在则会抑制3CaO·3Al2O3·CaSO4的形成.     

CH4-CaSO4和H2S-Fe2O3反应体系的热力学和动力学研究

The destruction of hydrocarbon in deep carbonate diagenetic environment is one of problems on the formation of oil and gas. Organic-inorganic reactions in the process of TSR(Thermochemical Sulfate Reduction) are the main reason to make disappearance of the hydrocarbons. The work in this field has often been the subject of much research work in recent years. In this paper, the thermodynamics of CH4-CaSO4 and H2S-Fe2O3 systems is discussed to investigate the possibility of reactions. It is found that these two reactions can proceed spontaneously.Increasing temperature is favorite for CH4-CaSO4 system but disfavorite for H2S-Fe2O3 system. Thermal simulation experiments were carried out using autoclave at high temperature and high pressure. The properties of the products were characterized by microcoulometry, FT-IR and XRD methods. On the basis of the experimental data, a reaction kinetic model is developed and kinetic parameters are determined.     

甲烷的二氧化碳重整动力学研究

The kinetics of CO2 reforming of methane has been studied at 976-1033K on a commercial NiO/CaO/Al2O3 catalyst in a packed-bed continuous reactor. The reaction was carried out at atmospheric pressure and CO2/CH4 ratio > 2. The Hougen-Watson rate models were fitted to experimental data assuming the dissociative adsorption of methane as the rate-determining step. The reaction rate showed an effective reaction order of about unity for CH4. The apparent activity energy was found to be 104kJ·mol-1. Therefore the kinetic reaction parameters were determined and a possible reaction mechanism was proposed.     

Effect of Additives on Properties of MgO—ZrO2—C Material

The paper describes the effect of additives Al,Si,SiC and A4C on the expanson of MgO-ZrO2-C material after being coked.Theresults indicate that Al and Si were oxi-dized to form Al2O3 and SiO2 respectively,and then re-acted with CaZrO3 or stabilizer in c-ZrO2 to form calcium aluminate,spinel(MA),dicalcium silicate(C2S) and forsterite (M2S) ,Meznwhile,α-C2S ras transformed to γ-C2S and c-ZrO2 to m-ZrO2 when temperature changed.All the above reactions resulted in the decrease of the amount of Al4C3 and SiC and the increase in bulk volume,which caused the stucture of MgO-ZrO2-C material de-stroyed.Hence,contrary to the MgO-C material,when adding Al,and Si,the MgO-ZrO2-C material would be structurally deteriorated after heat-treatment and its strength and corrosion resistance decreased.     

Experimental Study on Composition Optimization for Refining Slag Containing BaO

Laboratory study was carried out on deep desulfurization of molten steel by CaO-Al2O3 based refining slag containing BaO at 1873K to achieve lower sulphur level in steel. A mathematical model of desulfurization was established with the methodology of quadratic orthogonal regression. According to the modle, the influence of Al2O3/CaO, MgO, CaF2, BaO in slag on desulfurization rate was analyzed. The results showed that the desulfurization rate almost linearly decreased with the increase of Al2O3/CaO, and it increased firstly then decreased when MgO and BaO content increased respectively, yet the trend is on the contrary as CaF2 content increased.Based on the comprehensive analysis, the optimum composition of the refining slag was achieved under the experimental conditions.     

WP/γ-Al2O3催化剂的制备、表征及加氢脱硫和加氢脱氮活性

Two series of WP/Al2O3 catalyst precursors with WP mass loading in the range 18.5%-37.1% were prepared using the impregnation method and mixing method, respectively, and the catalysts were then obtained by temperature-programmed reduction of supported tungsten phosphate (precursor of WP/Al2O3 catatlysts) in H2 at 650℃ for 4h. The catalysts were characterized by XRD, BET, TG/DTA, XPS and 31p MAS-NMR. The activities of these catalysts were tested in the hydrodenitrogenation (HDN) of pyridine and hydrodesulfurization (HDS) of thiophene at 340℃ and 3.0MPa. The results showed that owing to the stronger interaction of the support with the active species, the precursor of WP/Al2O3 catalyst was more difficultly phosphided and a greater amount of W species was in a high valence state W6 on the surface of the catalyst prepared by the impregnation method than that by the mixing method. 31p MAS-NMR results indicated that 31p shift from 85% H3PO4 of 2.55 × 10-4 for WP and 2.57 × 10-4 for WP/γ-Al2O3 catalysts prepared by mixing method. Such WP/Al2O3 catalysts showed higher HDN activities and lower HDS activities than those prepared by the impregnation method under the same loading of WP.WP/γ-Al2O3 catalysts with weak interaction between support and active species were favorable for HDN reaction while the WP/γ-Al2O3 catalysts with strong interaction were favorable for HDS reaction.     

一锅法从卟啉配体合成μ-氧代四苯基双核铁卟啉

A novel method for synthesis of substituted μ-oxo-bis [tetraphenyl porphyrinatoiron] compounds ([TRPPFe]2O) based on the reaction among free base porphyrins (TRPPH2), FeSO4·7H2O and H2O in one pot was proposed and investigated. Four kinds of [TRPPFe]2O were synthesized by this novel synthetic method, and their structures were characterized by elemental analysis, infrared spectra and UV-vis spectroscopy. The reaction conditions, including the effect of different iron salts on the formation of [TRPPFe]2O, the reaction time between FeSO4·7H2O and TRPPH2, the molar ratio of FeSO4·7H2O/TRPPH2 as well as the volume ratio of H2O/DMF, were investigated. The [TRPPFe]2O yield of 93%-98% could be obtained under the following optimal conditions: the reaction time of FeSO4·7H2O with TRPPH2 was about 10h, the molar ratio of FeSO4·7H2O/TRPPH2 about 5:1, and the volume ratio of H2O/DMF exceeded 2:1. Further research indicated that only TRPPFeCl were formed once FeSO4·7H2O was replaced by FeCl2·4H2O, the reason of which might be that halogen ions in iron salts interfered the formation of [TRPPFe]2O, suggesting that halogen ions should be avoided in this novel synthetic method.     

La2O3助剂对甲烷干燥重整催化剂 Ni-γ-Al2O3支撑作用的研究简

The nature of support and type of active metal affect catalytic performance. In this work, the effect of using La203 as promoter and support for Ni/γ-A1203 catalysts in dry reforming of methane was investigated. The reforming reactions were carried out at atmosphenc pressure in the temperature range of 500-2700℃. The activity and stability of the catalyst, carbon formation, and syngas （H2/CO） ratio were determined. Various techniques were applied for characterization of both fresh and used catalysts. Addition of La2O3 to the catalyst matrix improved the dispersion of Ni and adsorption of CO2, thus its activity and stability enhanced.     

Self-assembled bright luminescent hierarchical materials from a tripodal benzoate antenna and heptadentate Eu(III) and Tb(III) cyclen complexes

The europium heptadentate coordinatively unsaturated (Eu(III)) and the terbium (Tb(III)) 1,4,7,10-tetraazacyclododecane (cyclen) complexes 1 and 2 were used in conjunction with ligand 3 (1,3,5-benzene-trisethynylbenzoate) to form the supramolecular self-assembly structures 4 and 5;this being investigated in both the solid and the solution state. The resulting self-assemblies gave rise to metal centered emission (both in the solid and solution) upon excitation of 3, confirming its role as a sensitizing antenna. Drop-cased examples of ligand 3, and the solid forms of 4 and 5, formed from both organic and mixture of organic-aqueous solutions, were analyzed using Scanning Electron Microscopy, which showed significant changes in morphology;the ligand giving rise to one dimensional structures, while both 4 and 5 formed amorphous materials that were highly dense solid networks containing nanoporous features. The surface area (216 and 119 m2·g^-1 for 4 and 5 respectively) and the ability of these porous materials to capture and store gases such as N2 investigated at 77 K. The self-assembly formation was also investigated in diluted solution by monitoring the various photophysical properties of 3–5. This demonstrated that the most stable structures were that consisting of a single antennae 3 and three complexes of 1 or 2 (e.g., 4 and 5) in solution. By monitoring the excited state lifetimes of the Eu(III) and Tb(III) ions in H2O and D2O respectively, we showed that their hydration states (the q-value) changed from -2 to 0, upon formation of the assemblies, indicating that the three benzoates of 3 coordinated directly to the each of the three lanthanide centers. Finally we demonstrate that this hierarchically porous materials can be used for the sensing of organic solvents as the emission is highly depended on the solvent environment;the lanthanide emission being quenched in the presence of acetonitrile and THF, but greatly enhanced in the presence of methanol.