What is a RenoCell?
RenoCell is a patented electrolytic cell that uses a state of the art electrochemical cell design to remove metal ions from aqueous, inorganic and organic fluids.
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What is a "divided" RenoCell?
For certain applications, a variation of the standard RenoCell is available, the "divided" RenoCell. This divided RenoCell has a hydroscopic membrane (normally a cation exchange membrane) positioned concentrically between the cathode and the anode. In this case, two electrolyte solutions, anolyte and catholyte, and consequent dual solution storage, circulation and control systems, are required. The divided RenoCell system can be applied to solutions containing species that can be oxidized at the anode and that would interfere with the cathodic deposition process, e.g., chlorine generation from aqueous chloride solutions.
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How much better is RenoCell than existing technologies?
In general, RenoCell is capable of two to three orders of magnitude lower final concentration of metal ions, and three to ten or more times higher current efficiency than other commercial electrochemical cells at concentrations between 50 and 5 PPM. The current efficiency improvement is even higher (infinite in some cases) between 5 and 0.1 PPM (or even 0.01 PPM for some applications). Such low concentration levels are not even possible by present commercial electrochemical cells.
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What does a cathode look like as it becomes plated with metal?
Copper recovery on an M500 cathode is shown in Photos 1, 2 & 3 in early stages of metal deposition. Metal deposits grow first near the current feeders down the length of the cathode on both sides, and around the top and bottom edges where electropotential and flow velocities (i.e., mass transfer coefficients) are greatest. As these areas fill with metal, both flow and electropotential are distributed throughout the remaining volume of carbon which then also begin to fill with metal until virtually the entire cathode carbon element is loaded with metal.
Metal deposition on cathode, Photo 1
Metal deposition on cathode, Photo 2
Metal deposition on cathode, Photo 3
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What kind of payback can I expect?
Compared to conventional treatment technology and the waste disposal and other life cycle costs, an investment in RenoCell technology can easily deliver complete return on investment in 18 months or less? often as little as two to four months.
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Why should I consider RenoCell as a solution to my waste metal problem?
If you have waste metal solutions, RenoCell offers some powerful benefits. You can remove up to 100% of the metal ions for recovery or reuse. You can dramatically reduce environmental liability while reducing and controlling costs. You can preclude waste storage and treatment regulations and comply with pollution prevention goals. Most of all you can save money.
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I worked some years ago with another electrolytic cell the couldn't reach PPM levels for metals. What has changed?
Many electrolytic cells have been proposed for metal recovery over the past two decades. They have been used mostly as concentrators where further stages of treatment are required to remove all the metal in the solution. The most common configurations include parallel flat plate cathodes, reticulated cathodes, and high surface area cathodes. Various cell designs were developed to minimize the mass transport limits and reduce the equipment footprint and costs. Some of the most common cells include the carbon particle packed bed (ER cell); fluidized bed beads within electrodes (Chemelec cell); vertical metal or carbon foam electrodes (Retec cell); and various cylindrical rotating cathodes (Eco-Cell). Unfortunately, the performance of these conventional electrochemical cells is limited at low metal ion concentrations. While some of these cells can be effective down to metal ion concentration levels of around 50 - 150 PPM, effluent discharge levels are typically less than 5 PPM and often below 1 PPM. RenoCell has changed all of this.
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What types of metals are suitable for RenoCell?
We've proven the technology with a wide range of metals in many different solutions and combinations. In brief, if the metal is platable, then RenoCell will perform better than any other commercial cell; in some cases if the metal will electroprecipitate, such as Cr(IV)?>Cr(III), RenoCell will also perform very well. The most common metals that we have extensive experience include copper, gold, silver, tin, lead, nickel, palladium, platinum and cadmium.
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In what types of metal finishing applcations has RenoCell been used?
RenoCell has application in various metal finishing operations involving concentrated baths, rinse and effluent treatment. These point source uses of RenoCell include bath dumps, rinse maintenance and ion exchange enhancement. The potential of waste minimization is currently being realized in both new plating line installations and retrofit upgrades of existing operations.
Metal deposition on cathode, Photo 1 Metal deposition on cathode, Photo 2> Metal deposition on cathode, Photo 3
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Are electrochemical processes and cells new?
Electrochemical processes have been studied in some depth since the early 1900?s but it is only since 1960 that the field of electrochemistry has been widely studied and developed. While electrochemical cells have been used most of the 20th century, it is only in the past 30 years that widespread application of advanced electrolytic cell designs such as RenoCell has been realized. In the past 20 years a number of new and innovative cell designs have substantially expanded the role of this technology.
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Where is an eletrochemical cell used?
Electrochemical cells are commonly used in a variety of industrial applications ranging from chemical synthesis to power generation to metal recovery and waste effluent treatment. Common applications relating to metal removal or recovery include:
* Primary ore leaching
* Mine leaching or runoff water
* Electroplating spent bath and rinse water
* Etching solutions and rinse waters
* Metal-cleaning solutions
* Precious metal reprocessing and refining
* Catalyst liquors
* Photoprocessing solutions
* Effluent treatment
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Is this technology mature?
The advancement in and development of electrochemical cell designs has resulted in the availability of a versatile range of electrodes, membranes, reactors and sensors, together with improved power supplies and control strategies. In addition, reliable laboratory instrumentation allows fundamental experiments in the laboratory, improving knowledge of mechanisms and kinetics of electrode reactions. In this context, RenoCell is a mature technology implemented in a commercial product line with some 8 years of actual field development and testing.
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How does an electrolytic cell work?
Electrochemical reactions are heterogeneous chemical reactions that occur through the transfer of charge across the interface between an electrode and an electrolyte. The basic design of any electrolytic cell is the same and requires a complete electrical circuit including: electrodes (an anode and a cathode); ionic contact via an electrolyte between the electrodes; and electrical contact via an external electrical circuit between the electrodes. The metal is plated at the cathode; in RenoCell?s case on a 3-D carbon felt-like material.
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How does ion exchange and chemical precipitation, used to remove metal ions, compare with electrolytic cell or reactors?
Both ion exchange and chemical precipitation are well-established unit operations, each with its own individual strengths and applications. However, these processes essentially only lead to a precipitated salt or another metal ion solution of increased concentration that, depending on the circumstances, require a variety of additional steps (and costs) to handle the metal ions. The performance of the high surface area cathode used in the RenoCell now adds this electrolytic cell to the choices available to the companies with metal wastes problems. The major advantage of RenoCell-based processes is that the metal can be removed to below PPM levels and recovered directly, in its most valuable form? solid metal.
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Where is the RenoCell manufactured?
RenoCell component fabrication is sourced from a number of companies in the U.S., the Pacific Rim and Europe. At present assembly is done at Renovare?s facilities in the San Francisco Bay Area.
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Where are RenoCell based systems produced?
RenoCell-based systems are provided through a networked of highly skilled and qualified resellers and system integrators. These experienced firms provide not only the necessary hardware and controls necessary for a successful RenoCell application, but also the installation, startup and operational support required to fully realize the benefits of this technology. RenoCell systems are produced around the world including resellers located in the U.S., Europe and the Pacific Rim.
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How does RenoCell work?
RenoCell is based on the same electrochemical processes as any other electrolytic cell. However, the unique patented technology incorporated in the RenoCell provides significantly enhanced performance impossible with conventional commercial electrolytic cell design.
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How does RenoCell achieve its efficiencies?
The RenoCell allows effective use of three-dimensional (3-D) cathode materials, in this case a porous carbon felt through the flow path and current distribution embodied in the RenoCell patented design. The use of a 3-D cathode greatly enhances the performance of the cell since the porous carbon felt has at least a 500 times greater real surface area than a 2-D electrode of the same nominal geometric size. The RenoCell makes this very high surface area available for metal deposition at higher current efficiencies, lower current densities and higher deposition rates for a given nominal cell size than commercial cells with 2-D or 3-D cathodes. The net result is that RenoCell can achieve lower final metal ion concentrations while using less energy to remove a given amount of metal from a metal ion bearing solution in less time.
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Can I test the RenoCell?
Yes, both laboratory-scale and on-site demonstration testing are available from your RenoCell reseller.
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