Slowpoke NA should given them all the PGM's.
Cheaper to just to Ruth-Pt as you only need a lead button.
But Pt-Pd-Rh is best at 60 grams with a nickel button.
Trop cher.
Rhodium (Greek rhodon meaning "rose") was discovered in 1803 by William Hyde Wollaston,[6] soon after his discovery of palladium.[7][8] He made this discovery in England using crude platinum ore that he presumably obtained from South America.[9]
His procedure involved dissolving the ore in aqua regia, neutralizing the acid with sodium hydroxide (NaOH). He then precipitated the platinum by adding ammonium chloride, NH4Cl, as ammonium chloroplatinate. All other metals like copper, lead, palladium and rhodium were precipitated with zinc. Diluted nitric acid dissolved all but palladium and rhodium, which were dissolved in aqua regia and the rhodium was precipitated by the addition of sodium chloride as Na3[RhCl6]·nH2O. After washing with ethanol the rose red precipitate was reacted with zinc forming rhodium metal.
he primary use of this element is in automobiles as a catalytic converter, which converts harmful emissions from the engine into less harmful gases.[11][12]
[edit] Catalytic converter
Cross section of a Metal-core Converter
In 2007 81%[11] of the world production of rhodium was consumed to produce three-way catalytic converters.[11] Rhodium shows some advantages over the other platin metals in the reduction of nitrogen oxides to nitrogen and oxygen:[13]
2NOx ? xO2 + N2
The recycling of catalytic converters also became a valuable source for rhodium. In 2007 5.7 t were extracted from this source. Compared to the 22 t which have been mined, this is a relatively high recycling rate.[11]
[edit] Other uses
Rhodium is used as an alloying agent for hardening and improving the corrosion resistance[14] of platinum and palladium. These alloys are used in furnace windings, bushings for glass fiber production, thermocouple elements, electrodes for aircraft spark plugs, and laboratory crucibles.[15] Other uses include:
* It is used as an electrical contact material due to its low electrical resistance, low and stable contact resistance, and its high corrosion resistance.
* Plated rhodium, made by electroplating or evaporation, is extremely hard and is used for optical instruments.
Rhodium plated white gold wedding ring
* This metal finds use in jewelry and for decorations. It is electroplated on white gold and platinum to give it a reflective white surface. This is known as rhodium flashing in the jewelry business. It also may be used in coating sterling silver in order to strengthen the metal from tarnish, as a result from the copper compound found in sterling silver. Solid (pure) Rhodium jewelry is very rare, due more to the metal having the dual characteristics of a high melting point and poor malleability (making such jewelry very hard to fabricate) than to the metal's high price.
* It is also a highly useful catalyst in a number of industrial processes (notably it is used in the catalytic system of automobile catalytic converters and for catalytic carbonylation of methanol to produce acetic acid by the Monsanto process). It is used to catalyse addition of hydrosilanes to a double bond, a process important in manufacture of certain silicone rubbers.
* The complex of a rhodium ion with BINAP gives a widely used chiral catalyst for chiral synthesis, as in the synthesis of menthol.
* It is also used as a filter in mammography systems because of the characteristic x-rays it produces.
* It is also used in high quality pen surfaces due to its high-resistance characteristics. These pens include Graf von Faber-Castell, Caran D'ache.
* Rhodium neutron detectors are used in Combustion Engineering Nuclear Reactors to measure neutron flux levels - a method that requires a digital filter to determine the current neutron flux level, as there are three signals generated: immediate, a few seconds later, and a minute later, each with its own signal level, and all three are combined in the rhodium detector signals. The three Palo Verde nuclear reactors each have 305 rhodium neutron detectors, 61 detectors on each of 5 vertical levels, providing an accurate 3-D "picture" of reactivity, allowing fine tuning to most economically burn the nuclear fuel.
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