Chemistry Commons^™

Fundamental Chemistry Of U And Pu In The Tbp-Dodecane-Nitric Acid System, Kenneth Czerwinski

Separations Campaign (TRP)

The research objective is to experimentally evaluate the fundamental speciation of Pu and U in the TBP-dodecane-nitric acid- AHA system and the effect of pertechnetate, specifically:

• To determine the influence of nitrate on the speciation of U and Pu in the TBP-dodecane-nitric acid system. The aqueous and organic speciation of U and Pu are examined as a function of the nitric acid concentration, nitrate concentration, actinide ion concentration, temperature, and time.

• To determine the speciation of U and Pu with AHA in the presence and absence of TBP-dodecane organic phase. The aqueous and organic speciation of U and …

Criticality Studies For Urex Processes, Denis Beller

Separations Campaign (TRP)

The completion of criticality experiments for mixtures of transuranic actinides (TRU; includes neptunium, plutonium, americium, and curium) that will be created during the separation of used nuclear fuel may be a requirement in order to construct prototype plants for the Global Nuclear Energy Partnership (GNEP). In this program and the Advanced Fuel Cycle Research and Development (AFC R&D) program that supports it, economic and environmental methods are being developed to reduce the impact of waste from commercial nuclear fuel cycles.

Recycling of used fuel by chemically separating it into U, fission products, and TRU would be the first step in …

F-Element Electrochemistry In Rtil Solutions: Electrochemical Separation Of Lanthanides And Actinides, David W. Hatchett

Separations Campaign (TRP)

Electrochemical methods can be used to effectively separate actinide and lanthanide species from complex mixtures. This is based on the unique electrochemical properties of each specific target species. In studies it has been found that, with the exception of Ce, aqueous solutions provide unsuitable electrochemical windows to effectively evaluate the thermodynamic properties that are useful for chemical separations. Therefore, a more novel approach was examined which eliminated the aqueous solution with a room temperature ionic liquid (RTIL) solution. RTIL solutions do not suffer from the side reactions that are prominent in aqueous environments. In addition, the potential window is much …

Evaluation Of Fundamental Radionuclide Extraction Data For Urex, Kenneth Czerwinski

Separations Campaign (TRP)

The speciation of technetium and actinides in advanced solvent extraction systems is the basis for their manipulation in separations. The ability to understand and predict radionuclide speciation is paramount to successful modeling of proposed separation systems. This project will examine the speciation of radionuclides in different stages of the uranium extraction (UREX) separation scheme, providing data useful to modeling. The areas to be examined include the speciation of uranium and plutonium with tributylphosphate and the kinetics and thermodynamics of lanthanides and actinides in the TALSPEAK (Trivalent actinide lanthanide separation by phosphorous reagent extraction from aqueous complexes) system. The complexation constants …

Interaction Between Metal Fission Products And Triso Coating Materials, Clemens Heske

Fuels Campaign (TRP)

This project focuses on the chemical bonding and interface formation of metal fission products with the coating materials used in tri-isotropic (TRISO) fuel particles for gas-cooled reactors. By combining surface- and bulk-sensitive spectroscopic and microscopic methods, intermediate chemical phases at the interface, intermixing/diffusion behavior, and the electronic interface structure for different coating materials and metals are examined.

In detail, the project studies the interface formation of Pd, Cs, and Ag with SiC and pyrolytic carbon. Using SiC single crystals and highly-ordered pyrolytic carbon (HOPG) as substrates, interfaces are prepared under controlled conditions in an ultra-high vacuum environment and are studied …

Solution-Based Synthesis Of Nitride Fuels, Kenneth Czerwinski, Tyler A. Sullens

Fuels Campaign (TRP)

One of the original synthetic routes devised for the synthesis of U (III)N involved the entire reaction taking place in liquid ammonia. Several experimental reactions were conducted in an attempt to synthesize the UI₃(NH₃)_x and U(NH₂)₃(NH₃)_x precursors of U(III) N. Each attempt involved cleaning of the uranium metal to remove the oxide coating of the metal reagent with 3 washes of concentrated nitric acid, each followed by a rinse with liquid ammonia. Success of this cleaning procedure was varied, with a majority of cleaned metal oxidizing rapidly once …

Improved High-Temperature Stability And Sun-Light-Driven Photocatalytic Activity Of Sulfur-Doped Anatase Tio2, Suresh Pillai, Declan Mccormack, Pradeepan Periyat, John Colreavy, Steve Hinder

Articles

No abstract provided.

Molten Salt Systems And The New Developments For The Application Of Molten Salts, Peng Liu, Ye-Xiang Tong, Qi-Qin Yang

Journal of Electrochemistry

The general situation of molten salt systems since 21 century are presented.The development of room temperature molten salts are emphasized.Applications of molten salts to the areas of preparating alloys and functional materials;batteries and capacitors;analysis and separation;use as reaction media and catalyzers;environmental protection have good prospect.In order to continually develop the molten salt system,it is necessary further to know the properties of molten salts and relevant theories,as well as exploiting the new methods and novel systems of synthesizing molten salts.

Electrochemical Oxidization Of Herring Sperm Dna And Its Interaction With Histone, Juan Xu, Gui-Ping Huang, Hong Li, Wei Zhu

Journal of Electrochemistry

The voltammetric behavior of herring sperm DNA at glassy carbon electrode and its interaction with histone have been investigated by using cyclic voltammetry,differential pulse voltammetry,and fluorescence measurement.In the potential range of 0.20 V to 1.25 V,it is found that an irreversible oxidative peak is exhibited in acid solution,but in the neutral or alkaline solution two oxidative peaks are observed.Oxidative peak potential values show a negative shift with increasing pH via a slope of-57 mV·pH-1 and a linear relation with DNA concentration in the range of 0.45 to 8.20 mmol·L^-1.In the presence of histone,the oxidative peak current of DNA …

Eiectro-Oxidation Of Methanol On Pdnio/C Catalyst In Alkaline Medium, Mei-Li Wang, Lin Sang, Cheng-De Huang

Journal of Electrochemistry

The electro-oxidation of methanol in alkaline electrolyte at in-house synthesized PdNiO/C and Pd/C catalysts and the effect of heat treatment on the structure and performance of catalysts were studied by cyclic voltammetry,chronoamperometry,chronopotentiometry and X-ray diffraction methods.It is shown that when the reduction temperature is 70℃ and the ratio between Pd and Ni is 8∶2,The PdNiO/C catalyst presents a highest activity for methanol electrooxidation.Calcining can increase the particle size and crystallinity of catalysts,but decrease the dispersion and activity of catalysts, too.Besides,the NiO is disengaged from Pd lattice by heat-treatment.The optimal PdNiO/C catalyst shows higher catalytic activity and much better poisoning resistance …

Preparation And Properties Of High Capacity Lifepo4, Jun Li, Gui-Tang Lai, Hui-Min Huang, Da-Guang Li, Xin-De Xia

Journal of Electrochemistry

Carbon-doped LiFePO₄/C and pure phase LiFePO₄ cathode materials were prepared by liquid-state precipitation reaction. The results of XRD, SEM, elemental analysis,FTIR and A.C.impedance tests show that the samples have had olivine structure and a 3.4V discharge platform.The tapped density of LiFePO₄/C sample could reach 1.46g/cm³, the initiate discharge capacity is 144.6mAh/g at 0.1C,which remained capacity is 93.2% after 20 cycles. The first discharge capacity is 133.5mAh/g at 1C and the capacity decreased 8.76% after 20 cycles.

Electrochemical Behavor Of Zinc-Indium Alloy Electrodes In Concentrated Alkaline Solution, Zhi-Lin Wang, Xiao-Ge Zhang, Rong-Gui Du, Chang-Jian Lin

Journal of Electrochemistry

The electrochemical behavior of zinc-indium alloy electrodes in 35%KOH solutions has been investigated by electrochemical methods including the potentiodynamic polarization and discharge measurements under constant current density.The results indicate that the anodic current density and passive current density increase after the indium addition.The discharge measurement shows that the addition of indium shortens the time to passive state for the Zn alloy compared to pure zinc at a large discharge conditions,that is the addition of indium may enhance the electrochemical activity of Zn alloy electrodes.It is found that the anodic dissolution of zinc-indium alloy electrodes in the concentrated KOH solution occurs …

Study On The Corrosion Of Chlorine Condenser By Electrochemical Method, Bin Xiang, Wen Chen, Wen-Zhang Huang, Shao-Hua Xing, Sheng-Tao Zhang

Journal of Electrochemistry

Corrosion of condenser is very seriously in chlorine-alkali industry,which could lead to fatal disaster.The most commonly used material in low pressure condenser includes steel of 16MnR,10#,and welding rod of J507.Electrochemical analysis of the three materials in 29.9%(by mass) calcium chloride(CaCl₂) solution was carried out.The corrosion current density icorr and impedance parameters of the three materials in 29.9% CaCl₂ solution were estimated separately.The result showed that in the tripartite phase regions where the 10# seamless tube and 16MnR armor plate were jointed by welding,the weld was firstly eroded and suggested that the chlorine condenser should be examined and …

Voltammetric Behavior Of Rutin And Its Application, Zong-Yao Qian, Bing-Qi Li, Hong Liu, Xin-Fu Xia, Yin-Mei Wang, Ya-Ping Niu

Journal of Electrochemistry

In solution of 0.1mol/L Tris-HCl(pH=8.3),a sensitive reduction peak of rutin was obtained by liner sweep polarography.The peak potential was-1.10V(vs.Ag/AgCl).The peak current was proportional to the concentration of rutin over the range of 7×10^-7～9.8×10^-6mol/L.This method has been applied to the determination of the flavonoid in G.Uralensis.The results showed that the reduction process was irreversible with adsorption that studied by linear sweep and cyclic voltammetry.

Study On Metal|Solid Electrolyte|Gel Membrane Containing Water|Graphite System, Jing-Dong Liu

Journal of Electrochemistry

The characteristic of oxide layer formed on the surface of metal in Metal|Solid Electrolyte|Gel Membrane Containing Water|Graphite System was studied by using Point Defect Model and Barrier Layer/Porous Layer Model.Trace water in solid electrolyte helped to form porous layer at the surface of metal,The thickness of porous layer increased due to water molecule reacts with barrier layer continuously,which lowered the porosity and decreased the electromotive potential and current.Porosity influenced solubility behavior of oxide layer intensely.Like barrier layer,porous layer is also a semiconductor.

Determination Of Malathion Based On Carbon Nanotubes Modified Electrode Incorporating Acetylcholinesterase, Lu Zhang, Yao-Dong Zhang, Hong-Lan Qi

Journal of Electrochemistry

A biosensor for determination of organophosphorus pesticide based on the acetylcholinesterase and multi-wall carbon nanotubes modified electrode is fabricated.Under the optimal conditions,the chronoamperometric current at +0.70V(vs.SCE) increased linearly with the concentration of malathion in the range from 6.0×10^-10 to 6.0×10^-9 mol·L^-1 with a detection limit of 1.0×10^-10 mol·L^-1.The recoveries of malathion in lake water is 97% to 105% determinated by this method.

Ion-Implanting Modification Of Layered Manganese Dioxide And Its Electrochemical Performance, He-Ning Huang, Dong-Ping Lv, Xing-Kang Huang, Qi-Wei Zhang, Yong Yang

Journal of Electrochemistry

Layered MnO₂(δ-MnO₂) was prepared by thermal decomposition of potassium permanganate.Ti was ion-implanted into such δ-MnO₂ by physical techniques,forming a composite(δ-MnO₂-Ti).These materials were characterized by XRD,SEM,XPS techniques and their electrochemical proprieties were investigated.The results showed that the layered structure of δ-MnO₂ did not been destroyed after Ti ion implantation,and the implanted Ti element was mainly Ti⁴⁺ as indicated by XPS.Both of the first and the highest discharge specific capacities of the ion-implanted layered MnO₂(δ-MnO₂-Ti),compared to those of δ-MnO₂,were improved significantly.

Electrochemical Behavior And Determination Of Luteolin At A Glassy Carbon Electrode, Ai-Lin Liu, Shao-Bo Zhang, Xiao-Sha Wu, Li-Ping Li, Yang-Yuan Cao, Li-Ying Huang, Xin-Hua Lin

Journal of Electrochemistry

The electrochemical behavior of luteolin was studied by voltammetry at a glassy carbon electrode in phosphate buffer solution.The results exhibited that the well-defined redox peak of luteolin is observed and the electrode process is adsorption-controlled.The charge transfer coefficient(α) was calculated as 0.66 in phosphate buffer solution(pH 4.0).The relationships between oxidation peak current and the concentration of luteolin are linear in the range of 1.0×10^-8 ～ 5.0×10^-6 mol·L^-1 by differential pulse voltammetric method.The detection limit had been estimated as 1.0×10^-8 molL^-1.This method can be used for the determination of luteolin with satisfactory results.

Selection Of Additions In The Process Of Electrochemical Synthesizing Of K2Feo4, Wei-Hua Yang, Dong-Qin Bi, Yan Zhou, Hong-Hui Wang, Xin-Ren Lan

Journal of Electrochemistry

Some of different additions including KIO₄ was added to the anodic electrolyte for electrochemical synthesizing of K₂FeO₄,the effects of these additions on current yield were investigated.XRD and SEM were used to characterize the structure and image of K₂FeO₄.The results show that KIO₄ is a preferable addition.When the mass dosage of KIO₄ is 0.02%,electrolysis time is 1 h,the current yield is enhanced by 31.6% and the corresponding purity of the product is improved by 3.85 %.

A New Method To Reduce The Contact Resistance Between Metal Current Collector And Graphite Plate For Pemfc, Hao Sun, Ming Han, Meng-Kai Liu, Jun-Bo Jia, Yao-Tian Zhan

Journal of Electrochemistry

A new method to reduce the contact resistance between metal current collector and graphite plate for PEMFC has been proposed.It was found that the contact resistance between the stainless steel current collector and graphite plate after embedding a metal net-carbon polymer composition is effective by to eliminate,Fuel cell testing has presented that this new method can effectively reduce the internal resistance of PEMFC,and improve the performance of the PEM fuel cell.

Electrochemical Behavior Of Zinc Alloy Anode In Ca(Oh)2 Solutions Of Different Ph, Peng-Ying Ren, Ji-Quan He

Journal of Electrochemistry

The polarization curves of zinc alloy anodes in Ca(OH)₂ solutions have been measured by potentiodynamic method,and the composition of corrosion products were examined by X-ray-diffraction(XRD).The experimental results indicated that not only the electrochemical behavior of zinc alloy anodes were absolutely different in every alkaline solutions,but also many electrochemical parameters were determined,such as zero current potential(E0),the density of corrosion current(icorr),passive current density(ip),breakdown potential(Eb),and so on.There were three zero current potential when zinc alloy anodes in some Ca(OH)₂ solutions which made passive state unstable.The graphs of E-pH about zinc alloy anodes dipped in different Ca(OH)₂ solutions were drawn,and compared …

Study On Electrochemical Impedance Spectroscopy Of Carbon Steel Eroded In Methyldiethanolamine Solution, Dong-Ping Wei, Rong-Zong Hu, Dan-Mei Pan, Wei-Xiong Huang, Rui Dong

Journal of Electrochemistry

Corrosion behavior of carbon steel in methyldiethanolamine(MDEA) solution was investigated by Electrochemical Impedance Spectroscopy(EIS).The results were showed that the corrosion rate of carbon steel in solution containing dissolved oxygen is higher than that in solution removed of dissolved oxygen before cathodic activation.They were reversed after cathodic activation.The corrosion rate is increased at first and then decreased when the concentration of MDEA is increased in the blank solutions.In the simulated solutions containing quantities of!heat-stable salts(HSS),the corrosion rate is decreased monotonously with increase of the MDEA concentration.As anodic polarization potential is increased,the EIS of carbon steel in HSS simulated solution showed characteristics …

Brief Account On The 4Th Cse Conference (November 3, 2007, Yangzhou), Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

A Circular On The 26Th Ccs Congress (July 13~16, 2008. Tianjin, China), Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Preparation And Investigations On The Tio2 Nanotube Arrays For Cathodic Protection Of 316l Stainless Steel, Jing Li, Hong Yun, Chang-Jian Lin

Journal of Electrochemistry

A highly ordered TiO₂ nanotube layer was fabricated by potentiostatic anodization of pure titanium in fluorinated electrolyte solutions. The structure and composition of the as-prepared TiO₂ nanotubes were characterized by SEM and XRD.The TiO₂ nanotubes show a stronger absorption in the ultraviolet(UV) light range. The performances of photogenerated cathodic protection and the photoelectrochemical response for the TiO₂ nanotube layers under illumination and dark conditions were evaluated through the electrochemical measurements. It is found that the open-circuit potentials of 316 SS coupled with the TiO₂ nanotubes layers shift negatively under UV light irradiation(λ<380nm). It is indicated that the TiO₂ nanotubes arrays …

Electrochemical Behavior Of Dill Pipe In 31%(By Mass) Nacl Solution Based New Type Inhibitor, Fu-Guo Liu, Min Du, Qing-Zhang Wang

Journal of Electrochemistry

The inhibitive effect of compound inhibitor including emulsifier(P), zinc sulfate, sodium polyphosphate, Glucose Gluconate was studied in 31% NaCl (by mass) solution. The inhibitory mechanism was analyzed by polarization curve and EIS. The results showed that the compound inhibitor was anodic-type inhibitor and its inhibitive effect on anodic and cathodal reaction was the most obvious at 200×10-6g·L^-1. And the results of EIS revealed that the inhibition efficiency increased and the film formed on electrode surface was more and more compact with time. Inhibition mechanism was different with concentration of inhibitor.

Construction Of Three-Dimensional Finite Element Model For Complicated Cathodic Protection System, Ai-Ping Wang, Min Du, Qing-Zhang Wang, Sheng-Shan Cao, Ji-Xing Sun

Journal of Electrochemistry

When condensers with carbon steel waterbox and titanium tube structure were protected by SACP in an ocean beach power plant,while seawater were used to be cooling water,carbon steel was under-protected and Titanium was over-protected,because their protective potential are less than-0.85V(vs.SCE) and more than-0.75V(vs.SCE) separately.In order to optimize the SACP design,potential distribution of two materials must be obtained during the SACP process.In the lab,carbon steel waterbox and Titanium tube model(Q235-Ti model) were set up.A series of electrochemical techniques(steady polarization,galvanostatic charge technique)were used to obtain reasonable boundary condition and surface form of two materials during the SACP process.The experiments were carried out …

Research Of 2,2′-Dipyridine On Electroless Copper Plating Using Sodium Hypophosphite As Reductant, Bin Yang, Fang-Zu Yang, Ling Huang, Shu-Kai Xu, Guang-Hua Yao, Shao-Min Zhou

Journal of Electrochemistry

In the bath of the electroless copper plating using sodium hypophosphite as reductant, the effects of 2,2′-dipyridine on the deposition rate, anodic oxidation of sodium hypophosphite, cathodic reduction of copper ions, surface morphologies, structure and the existing status of the deposit components were examined. The results showed that, 2,2′-dipyridine hindered the electroless deposition.Experiments of liner sweep voltammetry (LSV) indicated that,as the addition of 2,2′-dipyridine to the electrolyte, the oxidation peak potential of sodium hypophosphite shifted to a more negative value but the peak current decreased; the reducing peak potential of copper ions moved to a more negative value whereas the …

Oxygen Enrichment Effect Of Mno2-Pt/C Compound Catalyst To The Cathode Of Pemfc, Hong-Feng Xu, Mao-Feng Zhang, Quan-Quan Gan, Cai-Sheng Huang

Journal of Electrochemistry

TO study of the oxygen storage material of air cathode is crucial for increasing performance of proton exchange membrane fuel cell.Using the MnO₂ as oxygen storage materials,a MnO₂-Pt/C catalysts were prepared and is used to replace the conventional Pt/C in air cathode.The electrochemical performance of air cathode composed of MnO₂ supported on Pt/C and the properties of fuel cell composed of MnO₂-Pt/C were investigated by using the CV,galvanostatic dischange method and TEM.

Growth Mechanism And Morphology Of Electrodeposited Micro-Nanocrystalline Iron, Qiao-Xin Zhang, Jia-Ming Zhang, Li-Ning Yang

Journal of Electrochemistry

Effects of current density,reaction temperature,electrolyte concentration and surfactant on the electrochemical deposition of micro-nanocrystalline iron were studied.Morphologies and structures of the samples were characterized by SEM and XRD,the results showed that the electrodeposits is slice α-Fe under little current and the density,lower temperature and higher concentration,and the dentritic α-Fe is under opposite conditions,but the influence from surfactant is unconsicously.Moreover,the growth mechanism of the electrodeposits was also analysed here.