Precious Metals in Automotive Technology: An Unsolvable Depletion Problem?

Abstract

Abstract:Since the second half of the 20th century, various devices have been developed in order to reduce the emissions of harmful substances at the exhaust pipe of combustion engines. In the automotive field, the most diffuse and best known device of this kind is the "three way" catalytic converter for engines using the Otto cycle designed to abate the emissions of carbon monoxide, nitrogen oxides and unburnt hydrocarbons. These catalytic converters can function only by means of precious metals (mainly platinum, rhodium and palladium) which exist in a limited supply in economically exploitable ores. The recent increase in prices of all mineral commodities is already making these converters significantly expensive and it is not impossible that the progressive depletion of precious metals will make them too expensive for the market of private cars. The present paper examines how this potential scarcity could affect the technology of road transportation worldwide. We argue that the supply of precious metals for automotive converters is not at risk in the short term, but that in the future it will not be possible to continue using this technology as a result of increasing prices generated by progressive depletion. Mitigation methods such as reducing the amounts of precious metals in catalysts, or recycling them can help but cannot be considered as a definitive solution. We argue that precious metal scarcity is a critical factor that may determine the future development of road transportation in the world. As the problem is basically unsolvable in the long run, we must OPEN ACCESSMinerals 2014, 4 389 explore new technologies for road transportation and we conclude that it is likely that the clean engine of the future will be electric and powered by batteries.

Cobalt‐Catalyzed Reductive Alkylation of Amines with Carboxylic Acids

“…[14] Hence, it is necessary to find alternative metals that are earth-abundant, inexpensive, and environmentally friendly. [14] Hence, it is necessary to find alternative metals that are earth-abundant, inexpensive, and environmentally friendly.…”

Mineral Resource Depletion: A Coming Age of Stockpiling?

“…Again, the concept is similar to that of the role played nowadays by banks which offer their vaults to customers to safely store precious metals and other valuables. Here, customers could be attracted to commodities which, unlike gold, have a value that goes beyond pure speculation, such as, for instance, platinum and the platinum group metals (Bardi and Caporali 2014).…”

Closing the loop on platinum from catalytic converters: Contributions from material flow analysis and circularity indicators

“…For instance, in 2012, strikes by South African miners have impacted on production and may do so in the future (Sievers & Tercero, , March). –Declining ore grades: The average PGM concentration in the mines—for example, in South Africa—is below 10 g/ton (Hagelüken, ) and usually between 2 and 6 g/ton (IPA, ). In addition, the PGM industry is progressively forced to exploit lower grades and more expensive PGM ores (Bardi & Carporali, ), resulting in increasingly higher cost, as well as CO 2 emissions and energy consumption for the production of primary platinum. On the opposite, catalytic converter contains some 2,000 g/ton of PGM in the ceramic brick (Hagelüken, ) making their recovery attractive from a sustainability standpoint.…”