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Hydrothermal Synthesis and Structural Characterization of the Cage-based Arsenic-vanadium Microporous Material: [As_2V^(IV)_8V^V_2O_(26)]·8H_2O

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Chinese Chemical Letters 2004年第2期15卷 220-223页

作者： ShouTianZHENG YanQiongSUN GuoYuYANG CoordinationandHydrothermalChemistryGroup StateKeyLaboratoryofStructuralChemistryFujianInstituteofResearchontheStructureofMatterChineseAcademyofSciencesFuzhou350002 StateKeyLaboratoryofCoordinationChemistry NanjingUniversityNanjing210093

The complex of [As2VIV8VV2O26]8H2O 1 has been hydrothermally synthesized and characterized by IR, elemental analysis, EPR, TGA and single crystal X-ray diffraction analysis. The structure features of 1 are described.

关键词： Hydrothermal synthesis arsenic vanadium zeolite cluster.

THE DESIGN OF vanadium TRAPPING SYSTEM FOR FCC CATALYSTS

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Chinese Journal of Chemical Engineering 1996年第2期4卷 29-33页

作者：潘惠芳邬晓风唐爱军沈志虹藏高山石油大学（北京）应用化学系北京

The addition of distillation residues to the FCC feedstock leads to increased vanadiumloading on catalyst and the problems in catalyst *** deactivation process is related tothe destructive attack on the zeolite crystallite by V2O5.Formation of low melting pointV2O5-USY-Na2O phases accelerates the diffusion of vanadium through the catalyst.A proposedmechanism,based on accelerated dealumination,is shown in the *** vanadiumtrapping performances have been tested for FCC catalysts and the crystalline ABO3 as an effectivevanadium trap is demonstrated in laboratory tests.

关键词： FCC catalyst zeolite vanadium trapping

Influence of vanadium Element on Microstructure of Electron Beam Welded Titanium Alloy to Stainless Steel Joint

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稀有金属材料与工程 2011年第S4期40卷 49-53页

作者： Wang Ting,Zhang Binggang,Chen Guoqing,Feng Jicai State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Harbin 150001,China Harbin Inst Technol State Key Lab Adv Welding & Joining Harbin 150001 Peoples R China

Electron beam welding experiments of titanium alloys with different vanadium content to stainless steel,as well as alpha titanium to stainless steel using vanadium sheets as filler metal and transition portion were carried *** of the joints were examined by scanning electron *** properties were evaluated by microhardness and tensile *** was shown that electron beam welding is not feasible due to the brittle Ti-Fe intermetallics with high *** of vanadium content in base metal can restrain but can't avoid the formation of *** vanadium content was too large,the joint was embrittled by FeTi compound with supersaturated V and also cracked after *** free joint was achieved by using vanadium transition portion which can prevent the contact of Ti and Fe ***,the formation of brittle σ intermetallics reduced the tensile strength of the joint,only up to 134MPa.

关键词： titanium alloy stainless steel vanadium content microstructure mechanical properties

Extraction of vanadium from stone coal by modified salt-roasting process

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Journal of Central South University 2011年第6期18卷 1940-1944页

作者：王明玉王学文沈继峰乌日娜 School of Metallurgical Science and Engineering Central South University

In order to reduce the pollution of Cl2 and HCl released during extracting vanadium from stone coal by sodium chloride roasting, a modified salt-roasting process was proposed by adding calcined lime in roasting process followed by H2SO4 leaching. The effects of parameters including roasting temperature, roasting time, addition mass ratio of NaCI, calcined lime upon leaching rate of vanadium and curing rate of chlorine were investigated, and the effects of leaching time and leaching temperature on leaching rate of vanadium were also studied. The results show that the vanadium leaching rate and the curing rate of chlorine are 67.3% and 51.5% （mass fraction）, respectively, at roasting temperature of 750℃, roasting time of 4 h, 15% sodium chloride and 8% （mass fraction） calcined lime, leaching temperature of room temperature, and leaching time of 4 h.

关键词： vanadium stone coal salt-roasting chlorine curing

Improvement of Mechanical Properties of Cr-Ni-Mo-Cu-Ti Stainless Steel With Addition of vanadium

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Journal of Iron and Steel Research International 2007年第6期14卷 74-78页

作者： S M Abbasi A Shokuhfar Advanced Materials Research Laboratory K. N. Toosi University of Technology Tehran 165698391 Iran

The effect of vanadium （V） addition on the mechanical properties of a Cr-Ni-Mo-Cu-Ti stainless steel was studied and its influence on microstructural changes was also investigated. Results indicate that the structure of the solution-treated specimens mainly comprises of austenite-martensite, and adding V leads to the formation of a consid erable amount of ferrite. Under this condition, austenite phase is not mechanically stable, and transforms to martensite by plastic deformation. The addition of 0.5% - 1.0% （in mass percent） of V increases the hardness and the strength of the 80% cold rolled and aged steel, without any effect on ductility. Improvement in mechanical properties is presumably attributed to the formation of a small amount of ferrite in the primary structure, and the formation of certain precipitates is accelerated by the addition of V during aging. By contrast, excessive V decreases the strength and ductility simultaneously. This is due to the strong effect of ferrite formation compared to the beneficial effect of precipitation. The loss of ductility caused by adding higher amount of V is due to the formation of ferrite phases which in turn are suitable nucleation sites for crack propagation.

关键词： stainless steel vanadium microstructure mechanical property

Alumina Supported vanadium Oxide Catalysts for Residue Hydrotreating

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China Petroleum Processing & Petrochemical Technology 2013年第1期15卷 1-9页

作者： Jia Yanzi Li Dingjianyi Yang Qinghe Li Dadong Sun Shuling Nie Hong Research Institute of Petroleum Processing SINOPEC

In order to evaluate the role of vanadium in the hydrogenation (HYD) reaction, a series of alumina supported vanadium catalysts were prepared and characterized by SEM, XRD, Raman spectrometry, 51V NMR, XPS, as well as TPR analyses. The catalytic performance of vanadium in HYD of model molecules (naphthalene) and real feedstock (Kuwait atmospheric residue) was studied after sulfidation of the catalysts. It can be concluded that the HYD capabilities of V/Al2O3 catalysts are lower than that of conventional NiMo/Al2O3 catalyst (RefNiMo). The V/Al2O3 catalysts can only facilitate hydrogenation of the first ring of naphthalene, but have little effect on the further hydrogenation of tetralin. Owing to the different forms of metals and sulfur compounds in residue, the weak HYD activity of V/Al2O3 catalysts is able to facilitate the HDM reaction of the residue, albeit with a slight effect on HDS activity.

关键词： residue vanadium hydrodemetallization hydrodesulfurization

Effects of vanadium Oxidation Number on Light Olefins Selectivity of FCC Catalyst

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China Petroleum Processing & Petrochemical Technology 2011年第2期13卷 1-8页

作者： Liu Yujian Long Jun Tian Huiping Zhou Han(Research Institute of Petroleum Processing,SINOPEC,Beijing 100083) Research Institute of Petroleum Processing SINOPEC Beijing 100083 China

Effects of vanadium on light olefins selectivity of FCC catalysts were investigated with vanadium having different oxidation numbers （hereinafter abbreviated as Oxnum）. Molecular modeling studies showed that vanadium with low Oxnum could affect the chemical conversion of large-size hydrocarbon molecules. However, the vanadium deposited on equilibrium catalyst bad high Oxnum because of the oxidation reaction taking place in the regenerator, so an activation method to reduce vanadium Oxnum named ＂selective activation＂ was introduced. It was proved by means of Electron Paramagnetic Resonance （EPR） and Temperature-Programmed Reduction （TPR） methods that the vanadium Oxnum was decreased, when the catalyst was activated. The molecular modeling studies are consistent well with the lab evaluation results. The light olefins selectivity of activated equilibrium catalysts was better than that achieved by the inactivated catalysts. Similar results were observed with the lab vanadium-contaminated catalyst. The light olefins selectivity of the catalyst was optimized when the vanadium Oxnum was close to 2 （VO）.

关键词： FCC catalyst light olefins selectivity metal deposit oxidation number vanadium selective activization

Different Roles for vanadium as a Microalloying Element in Structural Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 29-38页

作者： Hutchinson Bevis SwereaKIMAB Swedish Corrosion and Metals Research InstituteBox 55970SE-10216 StockholmSweden

vanadium is the most versatile of the microalloying elements used in *** present paper describes three separate ways in which vanadium is used to optimize mechanical properties in different ***,precipitation of V(C,N) during the γ→α transformation or in ferrite during cooling provides strengthening that is especially useful in long products and ***,VN particles which precipitate in austenite act as efficient intra-granular nucleants for ferrite,contributing improved strength and toughness in suitable process routes such as seamless pipe ***,vanadium is supremely effective in preventing recovery in martensite and *** this way it can be applied to maintain strength and reduces variability of properties in hot rolled strip steels.

关键词： vanadium precipitation strength toughness

Synthesis and oxidative desulfurization activity of vanadium-substituted Keggin-type polyoxometalate hybrid compounds

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Tungsten 2024年第3期6卷 529-535页

作者： Min Xing Xiao-Ying Ji Shu-Xia Liu Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Department of Chemistry Northeast Normal UniversityChangchun 130024China

SO_(x) from fuel oil has caused much air ***,the desulfurization of fuel oil is *** desulfurization(ODS),as one of the most efficient nonhydrodesulfurization technologies,has become a major solution of desulfurization for fuel oil owing to its high reactivity for the removal of refractory organic sulfur compounds including dibenzothiophene(DBT)and its derivatives under mild reaction conditions[1].

关键词： substituted oxidative vanadium