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By Melvin H. Miles

"Considerable research has been conducted on the anodic oxidation of methanol in fuel cells. The electrochemical reduction of carbon dioxide in aqueous solutions to form methanol is the same reaction in reverse, i.e. CO2 + 6 H+ + 6 e- ? CH3OH + H2O. The same catalysts and conditions may operate for both reaction directions. This carbon dioxide reduction reaction, however, must be able to compete with the electrochemical reduction of water to form hydrogen gas. Thermodynamically, the reduction of CO2 to form CH3OH is slightly more favorable than the reduction of water. The use of nearly neutral electrolytes rather than acidic electrolytes makes the reduction of CO2 kinetically more favorable. The thermodynamics of various reaction steps are presented. Similarities exist with the electrochemical reduction of CO2 and the green-plant photosynthesis process that converts CO2 to carbohydrates.IntroductionVirtually all of the oxygen in the earth’s atmosphere is of biological origin having been generated by green-plant photosynthesis from water and carbon dioxide [1]. The net reaction can be represented byCO2 + H2O ? O2 + [CH2O] (carbohydrates, etc.) (1)Chlorophyll and enzymes promote this reaction, and the energy required comes from sunlight. The actual photosynthesis process is a complex multistage reaction and requires 469 kJ mol-1 of energy supplied by the sun. Isotope tracer experiments using 18O have shown that both the oxygen atoms in the O2 molecule originate from H2O, whereas oxygen atoms in the carbohydrates come from CO2 [1]. The total amount of water on the earth is split by photosynthesis and reconstituted by respiration and combustion once every 2 million years or so. The photosynthetically generated oxygen gas temporarily enters the atmosphere and is recycled about once every 2000 years [1]. The carbon dioxide is partly recycled in the atmosphere and oceans after an average residence time of 300 years and is partly fixed by precipitation of CaCO3 and other carbonate minerals [1]."

Jan 1, 2008

By Caisa Samuelsson, Sina Mostaghel, Theo Lehner

"Rönnskär smelter of Boliden Mineral AB, Sweden, is well known for recycling of base and precious metals. Slag from the electrical furnace is processed at the fuming plant to produce zinc clinker. The granulated slag is a by-product used as e.g. construction material. In this paper, influences of Al2O3 on mineralogy of the slag, which can affect its chemical and physical properties, are investigated. Different mixtures of Al2O3/fumed slag were prepared. Re-melting was carried out in a Thermo-Gravimetry (TG) furnace with an inert atmosphere. Scanning electron microscopy (SEM) and X-ray diffractometer (XRD) were then applied for the analyses. Investigations depict that addition of alumina to slag, results in an increase in the number of spinels and a transformation from iron rich to aluminum rich spinels. Anorthite (CaAl2Si2O8) will also be formed.IntroductionRönnskär smelter of Boliden Mineral AB is located in north of Sweden; the main products of this smelter are: Copper, Zinc clinker, Lead, Gold, and Silver, while sulphuric acid, liquid sulphuric dioxide, and Iron sand are some of the by-products. Reducing the energy consumption and decreasing the usage of finite natural resources are becoming more and more important for the Rönnskär smelter; this result in use of different recycling and scrap materials. Metal residues, from brass foundries, steel mills, and electronic scrap are recycled at Rönnskär smelter [1]. Most of the electronic scraps contain mixtures of various metals together with plastics and ceramics, which can affect the composition and properties of the slag considerably [2]. At the same time, treatment of slag and controlling its composition and properties are of much interest for Base Metals producers from different aspects. Composition of slag influences the physical properties such as: 1) Liquidus temperature [3-4] 2) Viscosity, which controls separation of valuable metals, especially copper by gravity separation [2] and also heat and mass transfer [5] 3) Electrical conductivity [6]."

Jan 1, 2008

By V. K. Handa

Sterlite Industries (I) Ltd. started its copper smelter in 1996 and worked through the common problems associated with smelter start-ups. Specific issues in the converter area included converter blower IGV problems, punching machine reliability, converter spitting, back collar burning, ,and short converter campaign life. With a very young and dedicated team of engineers and technicians, smelter management assigned teams of three to four members to work scientifically and systematically through each major problem area to recommend and implement appropriate solutions. The converter mouth was redesigned with respect to tuyere and metal height to eliminate spitting and back collar burning. The air line was changed in places to reduce the pressure drop. A new back-up compressed air line and vessel was installed to prevent tuyere blockage in the event of a blower trip or power failure. The converter mouth liners and bricking around the mouth was modified to eliminate metal leaking through the pouring lip Modifications to the punching machines were made to address specific problems and preventative maintenance practices were further streamlined and reinforced to ensure 100% availability of hot metal cranes, converter blowers, punching machines, and ID fans. Matte availability and matte temperatures were improved by streamlining the upstream ISA and Rotary Holding furnace areas. Implementation of a detailed training program for the converter operators significantly improved the operation and morale. Water-cooled double hoods and a third converter were installed as part of the smelter modernization plan. The new hoods dramatically improved hygiene in the crane aisle while the addition of the third converter posed new challenges for the same motivated group of crews with respect to flip flop operation to keep the idle converter hot and to maximize in-stack time, managing crane/ladle logistics, and managing revert generation. This paper describes the converter operation's journey from the initial days of long blowing times and large revert accumulations to present operations with two converter flip flop operation, and also describes the team work, constant focus on increasing productivity and reducing costs, and benchmarking.

Jan 1, 2002

New method for processing of copper and nickel production feed has been developed and tested at pilot unit having 10 t/hr capacity. The process allows single-stage treatment of ore feed including that with high magnesium oxide content and resulting in the production of rich matte, high-grade matte, or moralised alloy for further leaching, as well as dump slag and off-gasses suitable for production of elemental sulphur, liquid sulphur dioxide, or sulphuric acid. Tests results and principal technical and economical parameters are presented.

Jan 1, 2006

By Antonio Luraschi

The constituents iron, oxygen, silica and cop- per are of principal interest in slags utilized in pyrornetallurgical processes for producing copper. Accordingly, phase relationships in the.Cu-Fe-0-SiO2 system are important when one considers the physico- chemical behavior of slags. These phase relation- ships for the quaternary and constituent ternary systems are developed from available information. Isothermal composition and composition-oxygen potential diagrams, and oxygen potential-temperature diagrams are utilized to describe the' important relationships.

Jan 1, 1976

By R. Padilla, M. C. Ruiz, L. Salinas

Chloridizing roasting of bismuthinite (Bi2S3) with NaCl–O2 has been studied to remove the impurity Bi by volatilization from copper concentrates that contain bismuthinite. The study was conducted using mixtures of Bi2S3 and NaCl in a horizontal furnace and TGA apparatus. The variables were temperature, oxygen partial pressure, and NaCl concentration. The chlorination was analyzed by weight loss measurement method. XRD results of calcines reacted for short times in 21% O2, and 850–1000 °C showed the presence of Bi, BiOCl, and Na2SO4, while at longer times in the same conditions, Bi2O3 was identified as a stable phase. Thus, the chloridizing-volatilization of Bi2S3 proceeds through the formation of Bi and BiOCl. Temperature affected significantly the fraction of weight loss of samples. At 600 and 900 °C in 10.3% oxygen, the maximum weight loss was 4 and 20%, respectively. An increment in the partial pressure of oxygen in the range 1–21% affected negatively the Bi2S3 conversion. At normal roasting temperatures (550–700 °C), bismuth volatilization by NaCl roasting was found to be marginal.

Mar 1, 2017

A study of iron-removal from copper leachate by limestone precipitation followed by direct eltctrowinning of copper has been conducted. The influence of the process parameters: amount of precipitant, contact time, temperature, agitation intensity, solution acidity, and initial iron concentration on iron-removal was investigated. The effects of electrowinning time, cell voltage, solution acidity and temperature on electrowinning of copper were also investigated. The leachate contained 1.20 g/l cu2+ and 7.41 g/l total iron at pH 2.27. After contacting with 14 g/l precipitant for 2 hours, 97.5 % of the iron was attenuated and 98.4 % of the copper was recovered. With the following electrowinning conditions: 3 lead anodes, 3 stainless steel cathodes, 2.5 V, 39.41 A/m2 and 10.7 g/l H2S04, copper recovery-was 98.4 %. Purity of copper powder produced was greater than 99.0 %.

Jan 1, 1999

By Okechukwu Anopuo, Gerhard Tober, Petra Maier

"In this study, an investigation on the microstructure of hot rolled steel S355J2+N was conducted to optimize process parameters of complex forming, which combines rolling and bending. The best sets of parameters are worked out based on homogeneous mechanical properties and microstructure within the varied deformation degree with maximum at <p = 1.14 on a 25 mm thick plates. Mechanical properties, especially of heavy plates, are strongly influenced by the local deformation degree, strain rate and temperature. Detailed microstructural analyses showed that the ferrite-pearlite band structure changes near the surface, while maintaining homogeneous microstructure within the deformed work piece. Surface decarburization was also observed and this leads to decrease in hardness. To minimize iron oxide formation which could lead to side cracking, reduction in exposure time to temperature was suggested. On the other hand, temperature reduction below a critical value would risk the accurate forming process.IntroductionThis work presents the preliminary results of research to develop a new complex deformation process of thick steel plates. Complexity is given because the forming process combines rolling to reduce thickness and profiling by bending. The work piece will experience a thickness reduction from 25mm to 8 mm and is double curved. To explain and understand forming of thick plates basics of sheet forming as well as massive forming need to be used. At the moment there is no forming process established to produce double curved plates including reducing thickness in one process step. Technologies nowadays consist of two process steps: flat rolling and pressing in shape. Due to good weldability and formability the final product will be made of steel S355J2+N. This low-carbon steel is well understood and has a low strengthening exponent, which is expected to keep the forming forces down. Reduction of thickness from 25 mm to 8 mm gives furthermore a high deformation degree. Thus, hot forming has to be applied. The determination of process parameters is the main aim of overall research project; temperatures above lOOO°C are expected. Flow curves in literature are given at various temperatures and strain rates [1]. However, experiments with data close to the industrial application are rarely found, especially at low strain rates and high deformation degrees. Pre-test were done by flat rolling, being aware that the influence of bending is eliminated. The microstructure evolution were characterised in relationship to material formability with special attention to grain size change and recrystallization. Representative samples should be selected from specific locations in the deformation zone according to the knowledge about the metal forming process [2]. Due to no further alloying elements in S355, no precipitation hardening is expected to take place during hot forming, which keeps the mechanisms simple and the concentration on the feasibility of the complex forming process is given."

Jan 1, 2012

By Xiaobing Yang, Animesh Jha, Greg Doughty

"Successful use of inert anodes should reduce the CO2 footprint in aluminum production. The search for a “holy grail” inert anode for metal electro-winning from constituent oxides using molten salt bath as an electrolytic medium is continuing. In this article we demonstrate the engineering approaches for the fabrication of intermetallic anodes, based on a quaternary Al-Ti-Cu-M (M:Ni, Fe) system for primary aluminium production. In particular, we examine the microstructural and electrochemical properties of alloys, based on the quaternary compositions. We explain the aspects of phase stability under anodic potential, which leads to the loss of anodic materials in the temperature range of 850-1050oC. The results are analysed in the context of oxidation reaction and formation of oxide layers which readily dissolve in the cryolite melt and prevent passivation. The paper also describes the conditions under which the reduction of aluminium at the graphite cathode occurs which also strongly depends on the molten salt chemistry for the nucleation of molten aluminium at the cathode.1. IntroductionOxygen-evolving inert anodes are an alternative to the conventional consumable carbon anodes for the production of primary aluminium. In this paper the materials selection criteria chosen for the engineering of anode is based on the understanding of the thermodynamic stabilities of aluminide intermetallic phases, some of which are formed and remained stable in fluoride melts. For example, the formation Al3Ti dispersed in aluminium metal via molten-fluoride flux reaction is well known in the context of aluminium casting and grain refining [1-3]. It is for this reason in our research we concentrated on the engineering of stable intermetallic phase mixture in the Al-Ti-Cu ternary system, shown in Figure 1 [4]. In this figure two compositions in the Al3-0.5zTi1-0.5zCuz family are shown with the substitution of 7 atomic % and 11 atomic % copper. However initial investigations showed that these two compositions were unsuitable due to the formation of low-temperature liquid (~540oC) and intermetallic phase, Al2Cu along the Al-Cu binary edge during solidification. The Al2Cu phase segregated along the boundaries of Al3Ti and Al5Ti2Cu, and dissolved away when electrolysis was carried out using these anodes above 800oC. The presence of consequential porosity in the anode material increased the corrosion of the alloy through local heating due to high current density at 0.8 A cm-2. The early tests were carried out with cryolite melts, shown in Figure 2, having 3 weight percent of Al2O3 in the bath at 850oC."

Jan 1, 2010

By Akio Ohta

The Hyuga smelter has been producing ferronickel by a rotary kiln-electric furnace process in Miyazaki, Japan. Several approaches to improve our operation have decreased the electrical energy consumption. A new process was developed to decrease the cost of energy even further. Oil and technical oxygen are injected through lances to heat up the calcined ores (calcine) instead of the electric power. Main problems during the development of the process were the short life of the water-cooled lances, the check on security of the safety system and the eruption of combustion gases through the calcine bed. These problems have now been overcome successfully, and stable operation can be maintained. The addition of 1 Litre of heavy oil per tonne of ore can save the electrical energy requirement by 8.6 kwh per tonne of ore. The new process has resulted in a reduction of the electrical energy consumption by more than 10 percent

Jan 1, 1992

By Richard H. De Voto

The McDonald Gold Project and two satellite gold deposits near Lincoln, Montana, contain at least 9.9 million ounces of gold and 30 million ounces of silver. The McDonald gold deposit alone contains 7.2 million ounces of gold reserves that can be open-pit mined and processed by cyanide heap leaching at a projected cash operating cost of $190 per ounce. The deposit is predominantly oxidized with no chance of acid production, and can be mined, operated, and reclaimed with minimal permanent environmental disturbance other than the creation of an open pit filled with a fresh-water lake which would support trout. The Seven-Up Pete Joint Venture, the owner of the McDonald Gold Project, commenced permitting of an open-pit, heap-leach operation in November 1994. In 1998, Montana citizens passed an anti-cyanide, open-pit mining initiative, 1-137, which banned any new open-pit gold mine which uses cyanide processing, The Venture has conducted extensive studies, including metallurgical testing of the treatability of McDonald ores with alternative lixiviants, and has determined that all other mining and metallurgical treatment systems are vastly uneconomical in the recovery of gold and silver from the McDonald deposit. Therefore, the Venture&apos;s proposed open-pit mining and cyanide heap-leach processing is the only technology that can be applied economically to the McDonald deposit. Further, the analyses convincingly demonstrate that the proposed open-pit, cyanide heap leaching technology results in maximum resource conservation of this valuable and unique deposit and poses far less risk to human health and the environment than any of the alternative technologies.

Jan 1, 1998

By G.A Subagyo

The condition of slag in a pyrometallurgical reactor is vital to ensuring control of the process. A new technique based on multivariate image analysis (MIA) of digital images has been developed to provide an online measurement of important slag characteristics, such as the presence of exposed metal, the presence of solid phases, and temperature. This paper shall describe the technique and provide some results from analysis using industrial plant data.

Jan 1, 2003

By K. P. V. Lei

The U.S. Bureau of Mines investigated a hydrothermal sulfidation procedure to recover lead and silver from plumbojarosite. The plumbojarosite, generated during pressure-oxidative leaching of zinc concentrate in a commercial operation, contained, in percent, 25.4 pb, 18.8 Fe, 1.4 Zn, 29.5 SO,2-, 3.2 s?, 13.4 total sulfur, and 7.4 oz/ton Ag. The sulfidation was conducted in an autoclave and converted the plumbojarosite to amorphous iron oxide and liberated the lead and silver as sulfides. The best operating conditions were using 50 9 of plumbojarosite and 7 pct s? (2.04 9 S? added) in 500 mL of 2.0 mol/L NH3, 150? C, and 1 h. The sulfidation product contained, in percent, 37 Pb, 28 Fe, 6 S2-, 2 SO,2-, and 11.2 oz/st Ag. Ferric chloride leaching extracted 98 pct Pb and 97 pct Ag from the sulfidation product.

Jan 1, 1990

By Bernd Kopacek

"Nowadays more and more consumers substitute their conventional TV-sets and computer monitors by LCD panels. In the near future huge amounts of LCDs will start coming back to recycling. As LCDs with hazardous mercury backlight lamps are used an appropriate recycling technology has to be implemented.IntroductionLiquid Crystal Displays (LCDs) are widely used in notebooks, organizers, mobile phones, pocket calculators, measuring and control instruments, electronic games, hand-held miniature TVs, audio-video equipment, large signboards, automotive displays and more and more also for PC monitors and TVs.According to a study from Stanford Resources (San Jose, California) the annual value of LCDproducts reached 35 billion EUR in 2002, about 30% of this within the European Union, representing a total area of 2,1 million m2 Liquid Crystal Displays. An annual increase rate of about 15% is estimated for the next years (up to 4,1 million m2 in 2005).As LCDs are already on the market for several years, larger quantities of the more than 2,5 billion LCDs are coming into their End-of-Life stage for treatment. In 2005 this figure will become even more dramatic - 40.000 tons of LCD-modules contained in 2 million tons of waste electrical and electronic equipment (WEEE) or about 30% of total WEEE within EU. An amount which is representing 400 million EUR costs for incineration.Currently the only method used to deal with redundant LCD units is incineration or landfill. Both are expensive and causes emissions into the atmosphere (global warming) respectively water contamination (Class II) and difficulties in biodegradation. Up to now there is no recycling solution for LC-Displays available.As a consequence European Commission requests the disassembly of LCDs with an area bigger than 100 cm2 in the Directive 2002/96/EC of the European Parliament and of the Council on Waste Electrical and Electronic Equipment (WEEE Directive) of February 13, 2003."

Jan 1, 2008

By Peter Fischer

A demonstration plant for QSL technology with a continuous through-put of up to 10 t/h concentrate has been in operation at the Berzelius smelter, Duisburg, Germany since early 1981. In the QSL-process, both oxidation and reduction steps are performed in a single horizontal long cylindrical reactor. In the present demo-reacior, 2.5 M diameter by 22 M long, these steps are separated by a low partition wall with an underflow opening, to prevent backmixing of slag. -Tests on a variety of concentrates, including high-lead Missouri-type material and lower grades, have shown recoveries and consumables indicating very attractive economics. Investment cost estimates further enhance the economic attractiveness. Environmental protection afforded by the QSL system is a major advantage. The process has proven its reliability and versatility and is now ready for commercialization. Continued test work, including smelting secondary lead materials, is planned.

Jan 1, 1983

By Lars O. Werme

Already the KBS Project proposed copper as a suitable material for encapsulation of spent nuclear fuel. The basis for this choice was the thermodynamic stability of copper in water and the fact that deep granitic groundwaters in Sweden are oxygen free. With a limited supply of oxidants, a copper canister would have the potential for a very long service life. The research and development work aiming at encapsulating nuclear fuel entered a new phase in 1993, when SKB launched its Encapsulation Plant Project. Within this project, SKB has: ? designed a facility for encapsulation of nuclear fuel, ? laid down the design premises for a canister for disposal of nuclear fuel, ? tested and developed fabrication methods for copper canisters, ? evaluated the long term chemical and mechanical behavior of the canister, ? made preliminary plans for a factory for the production of copper canister, ? constructed a canister laboratory for full scale testing of the key operations in an encapsulation plant. The conclusions of this project were that a canister consisting of an outer layer (50 mm) of copper over an insert of cast nodular iron would provide sufficient corrosion protection and would have sufficient mechanical strength. This canister can be produced by several methods of which forming from rolled plates, hot extrusion, and "pierce and draw" have been tested at full scale. The canister will be sealed by electron beam welding in the encapsulation plant, and the integrity of the weld will be verified by ultrasonic testing and&apos; high-energy radiography. The final development work in this area will be performed in the canister laboratory.

Jan 1, 1999

By H. Kamiya, H. Hasegawa, M. Nojiri, S. Matsui, Y. Fukuda, M. Tsukada

"The present paper focuses on the action mechanism of anionic polymer dispersants in dense Si3N4 and SiC suspension. An atomic force microscope (AFM) was used to determine the relationship between the macroscopic suspension viscosity and the microscopic adsorbed structure of a polymer dispersant at the solid / liquid interface. The surface interactions within the suspensions were analyzed in various dispersant pH and additive conditions. The addition of an anionic polymer dispersant decreased Si3N4 and SiC suspension viscosity and increased electro-steric repulsion force on the non-oxide surface in solution at pH> 6 which was the isoelectric point of the materials. It was assumed that the increase of repulsive force was promoted by a hydrophobic adsorption of polymer dispersant on the non-oxide particles.IntroductionThe surface of silicon nitride and silicon carbide powders in a water suspension system has quite a complex molecular structure. In the case of Si3N4, hydroxyl and ammonium groups form on the surface and the pH of the suspension is increased from neutral to about 10 due to surface oxidation. The particle surface is negatively charged in alkaline solutions (pH=10), because the isoelectric point of silicon nitride exists in the pH range from 5 to 6. However, in spite of charging the negative surface charge, an anionic polymeric dispersant is generally used for the reduction in slurry viscosity.In dense SiC suspensions, an anionic polymer dispersant is generally used in order to disperse aggregates and reduce the suspension viscosity, too. Since an anionic dispersant is used in alkaline solutions higher than the isoelectric point of silicon carbide, the dispersant adsorbed on the negative charged surfaces of SiC.Few researchers have discussed and estimated the adsorption mechanism and structure of anionic polymeric dispersants on silicon nitride and silicon carbide surfaces. This is because it is difficult to observe the structure and measure the interaction at the solid/liquid interfuce directly. However, new developments in surface-force measurement technology have enabled the determination of non-DLVO type interaction for analyzing aggregation behavior2. The use of the AFM for analyzing the effects of various surfactants and co-polymers on colloidal dispersions and solid surfaces has also begun to rapidly expand to characterize the interaction between solid surfaces."

Jan 1, 2000

By M. K. Ghosh, B. C. Tripathy, A. Baral

Present work is focused on the recovery of Mn as a value added product from the leach liquor of scrap lithium-ion batteries (LIBs) of mobile phones by the method of precipitation. The LIBs were crushed and bene ficiated by wet scrubbing method to separate cathodic material, plastic and metallic parts. The cathodic material was found to contain 11.3% Mn, 10% Co, 2.4% Cu and 2.4% Li. The cathodic material was processed for leaching under the optimized condition developed by our group at CSIR-NML. Solvent extraction method was used to extract acid using organic extractant Tris(2-ethylhexyl)amine (TEHA) in order to reduce the consumption of alkali required during precipitation studies. The acid free leach liquor was subjected to puri fication for removal of Fe, Li, Cu and Co as precipitate at different pH. Systematic precipitation studies were carried in batch and continuous mode to recover Mn as Mn(OH) 2 at pH *10 which was further roasted at 450 °C for 4 h to get pure Mn 3O4.

Mar 1, 2018

By I. M. Santos Moraes

Achieving high current efficiencies when operating at high current densities is a goal for every refinery, whether conventional or permanent cathode technology is employed. To obtain higher current efficiency at increased current density at Caraiba&apos;s Tankhouse, the production team decided to change the cathode cycle from eleven to thirteen days, reducing cathode cycle to one per anode cycle. The idea was to reduce the anode-cathode spacing and consequently reduce the potential for short-circuiting them. With respect to current efficiency, the overall result was not much better than that obtained with the normal operating conditions. A new attempt to obtain higher current efficiency at high current density was implemented by going back to two cathode cycles per anode cycle, this time reducing cathode life to ten days. This approach yielded the highest current efficiencies. This paper presents the data generated with the three operating conditions: normal practice, a single cathode cycle per anode cycle, and two cathode cycles per anode cycle with a reduced cathode cycle time. It compares the productivity achieved with each set of operating conditions. An analysis of the main operating parameters as well as the advantages and disadvantages involved with each condition is also presented for future reference.

Jan 1, 1999

By Jr. Brown, A. Calderara, A. L. Antozzi

"The result of extensive research into fundamental mixed metal oxide catalyst morphology has produced a next generation all titanium Dimensionally Stable Anode (DSA ®). This new DSA ® anode, patent pending, is tailored for electrowinning of non-ferrous metals (copper, nickel, cobalt, zinc) by means of this new coating technology.These DSA ® anodes are characterized by a hanger bar with vertical distributor bars, having primary titanium mesh attached by weldments. The active mesh is provided with noble-metal electrocatalytic coatings, consisting of iridium and/or ruthenium oxides, obtained by thermal decomposition of precursor solutions applied to the titanium substrates. The catalytic activity of state-of-the-art DSA ® anodes is increased by controlling the crystallite size of the noble-metals without decreasing the decomposition temperature. It is known that below a certain value (typically 400°C) the stability of these oxides, and associated lifetime, is seriously compromised. A highly active DSA ® anode, consisting of a quasi-amorphous phase, is obtained at high temperature (above 450°C), therefore not compromising lifetime performance. Through optimization of these design parameters, the manufacture of these novel anodes was identified.DSA ® anode performance advantages include: lead-free ' green' all titanium anodes, true leadfree cathode quality, energy savings of 0.3 to 0.55 V can be realized depending on the EW application when compared to industry standard lead-alloy anodes, eliminate need for cobalt sulphate addition required for lead anodes, sustainability designed into long-life recoatable anode structures, increase plant cathode output through increased current density operations, improve plant on-stream production, no sludge generated or removed, and improve current distribution producing smooth high efficiency cathode.Introduction of ProductThere are many factors to consider when engineering a high performance DSA ® electrowinning anode. Half of the anode's performance is derived from the physical attributes of the electrocatalyst and methods employed when applying this catalyst to the titanium anode structure. The other half of the performance benefits relate to the proper structural design of the anode. In this paper, we will highlight the anode development program in which De Nora has invested to provide the Electrowinning marketplace with a high performance anode product."

Jan 1, 2012