Spark Plug Recycling Is A Thing, Because Iridium Is Too Expensive

It’s possible you’ll not think much in regards to the spark plugs in your automobile’s engine, but those small devices require precision manufacturing and helpful metals to maintain your vehicle humming. It’s common for a typical spark plug to feature steel, copper, and nickel, but many contain rare earth metals like platinum and iridium to increase the service life while maintaining engine performance. Iridium, particularly, is what makes these plugs among the many longest-lasting of the numerous spark plug types, because it’s probably the most corrosion-resistant material known to humanity. Iridium is incredibly hard, dense, and has a melting point of over 4,400 degrees Fahrenheit, making it well suited to automotive and performance applications.

Nevertheless, it so happens that iridium can also be one in every of the rarest elements on the planet, with the Earth’s crust only having around 0.000003 parts per million of iridium. Its rarity and superior properties are why iridium plugs are almost double the worth of platinum plugs, but automobile engines are only a small a part of the growing worldwide demand for iridium. The electrochemical industry uses about 3.1 tons of iridium annually, while electronics manufacturers devour 2 tons of it on average.

For spark plugs it’s about 1.7 tons per 12 months, which costs about $430 million based on the present market price of $7,900 per ounce of iridium. So yeah, iridium is rare, hard to get (mostly gathered from byproducts of nickel refining), and quite expensive. It is that this conundrum that led recent and revolutionary industry players to look into recycling iridium and other precious metals from old and used spark plugs. With iridium being scarce and with demand growing annually, we are able to only mine an excessive amount of of it before it’s gone.

It was that old spark plugs would find yourself in landfills or scrapyards for his or her steel content, with no efforts to get better the iridium or platinum content. Most often, recyclers will grind the iridium and platinum and blend them with the scrap steel, which essentially ends their lifecycle. It wasn’t until 2021 that spark plug recycling became a thing, and we all know why it took so long for industries to catch up in recovering the numerous precious metals that make up a spark plug.

For one thing, iridium’s hardness, very high melting point, and the low quantities of it in each plug previously made it difficult to extract for recycling. Earlier attempts to get better precious metals from discarded spark plugs were either too inefficient or labor-intensive to make sense economically. It’s the identical story with platinum. You almost certainly know the differences between platinum and iridium spark plugs, but platinum can also be one in every of the rarest precious metal on the planet (rarer than gold, take into consideration that). And with a 3,214-degree Fahrenheit melting point, platinum can also be difficult to recycle. Although 90% of the platinum in catalytic converters is recovered and reused, global recycling has declined by 17% as of 2024.

Nevertheless, things began to look up in 2023, when PGM Recovery, now rebranded Noble6, received a patent for an automatic system that extracts precious metals like iridium and platinum from spark plug electrodes. Its business model is a win-win, since shops and garages can ship used spark plugs and receives a commission, while manufacturers can reuse or repurpose the recycled metals to cut back their dependence on raw materials.

It’s hard to discern the environmental impact of something as common as a spark plug, nevertheless it’s substantial. An enormous chunk of money within the manufacturing of spark plugs goes on to the procurement of copper, platinum, and iridium. Extracting those precious metals from the earth consumes resources, contaminates the soil, disrupts the ecological balance of the world and its surroundings, and pollutes the air with greenhouse gas emissions from the machinery and equipment required for mining and extraction.

With 85% of worldwide iridium production coming from South Africa and Zimbabwe, there are humanitarian advantages to spark plug recycling, too, with miners often succumbing to silica exposure that results in tuberculosis and irreversible silicosis. Reducing our global dependency on freshly mined rare earth metals will help preserve whatever is left of our planet’s natural resources, help clean the air, and lower the price of production, which is sweet to your automobile and your wallet.

If you desire to be a part of the spark plug recycling movement, you’ll be able to receives a commission by sending old spark plugs in bulk to Noble6. Nevertheless, they only accept platinum and iridium plugs (double platinum plugs with more platinum content than odd platinum plugs are included) which can be undamaged, clean, and haven’t any oily stains or residues.