2019 has been declared by UNESCO as the Year of the Periodic Table. To celebrate, we are releasing a series of blogs about our favourite elements and their importance to the chemical industry. Today, we investigate the uses of platinum.
Around 1200BC, archaeologists discovered traces of platinum in gold in ancient Egyptian burials.
However, the extent of Egyptians’ knowledge of the metal remains unknown, which suggests that Egyptians might have been unaware that platinum existed in the gold.
The Ancient Egyptians made elaborate masks for royals to wear once they were mummified.
Platinum was also used by South Americans with dates going back 2000 years. Burial goods show that in the pacific coast of South America, people were able to work platinum, producing artifacts of a white gold-platinum alloy.
Archaeologists link the South American tradition of platinum-working with the La Tolita Culture. Archaeological sites show the highly artistic nature of this culture, with the artifacts characterised by gold and platinum jewellery, and anthropomorphic masks symbolising the hierarchical and ritualistic society.
What are its properties?
Platinum is a silvery white metal, also known as ‘white gold’. It is extremely resistant to tarnishing and corrosion and it is one of the least reactive metals, unaffected by water and air, which means it will not oxidise with air.
It is also very soft and malleable, and therefore can be shaped easily and due to its ductility, it can be easily stretched into wire.
Platinum is a member of group 10 of the periodic table. The group 10 metals have several uses including decorative purposes, electrical components, catalysts in a variety of chemical reactions and play an important role in biochemistry, particularly platinum compounds which have widely been used as anticancer drugs.
Additionally, platinum’s tarnish resistance characteristics makes it one the most well-suited elements for making jewelry.
Platinum bonds are often used as a form of medicine in treatments for cancer. However, the health effects of platinum are dependent on the kinds of bonds that are formed, levels of exposure, and the immunity of the individual.
In 1844, Michele Peyrone, an Italian chemist, discovered the anti-neo plastic properties (apparently prohibiting the development of tumours) and later in 1971, the first human cancer patient was treated with drugs containing platinum.
Today, approximately 50% of patient are treated using medicine which includes the rare metal. Scientists will look further into all the ways platinum drugs affect biology, and how to design better platinum drugs in the future.
Platinum is one of the most valuable metals in the world. Precious and pretty, it’s probably best known for jewelry – and that is almost certainly its oldest use. But its value has become far greater than its decorative ability; today, platinum powers the world. From agriculture to the oil markets, energy to healthcare, we use platinum far more than we realise.
1. Keep the car running
Platinum is needed to make fuel for transport. Image: Pixabay
Platinum catalysts are crucial in the process that converts naphtha into petrol, diesel, and jet-engine fuel, which are all vital to the global economy. The emissions from those petroleum fuels, however, can be toxic, and platinum is also crucial in the worldwide push to reduce them through automotive catalytic converters. In fact, 2% of global platinum use in 2016 was in converting petroleum and 41% went into reducing emissions – a circle of platinum use that’s more impressive than a ring.
2. Feed the world
Nitric acid is a by-product of platinum which is used in fertilisers. Image: Pixabay
Another vital global sector that makes use of platinum catalysts is agriculture. Without synthetic fertilisers, we would not be able to produce nearly as much food as we need. Nitric acid is essential for producing those fertilisers and platinum is essential for producing nitric acid. Since 90% of the gauzes required for nitric acid are platinum, we may need to use more of it as we try to meet the global food challenge.
3. Good for your health
A pacemaker. Image: Steven Fruitsmaak@Wikimedia Commons
Platinum is extremely hard wearing, non-corrosive, and highly biocompatible, making it an excellent material to protect medical implants from acid corrosion in the human body. It is commonly used in pacemakers and stents. It is also used in chemotherapy, where platinum-based chemotherapeutic agents are used to treat up to 50% of cancer patients.
4. The fuel is clean
In addition to powering the cars of the present and reducing their environmental impact, platinum might well be crucial to the future of transport in the form of fuel cells. Platinum catalysts convert hydrogen and oxygen into clean energy, with water the only by-product.
5. Rags to riches
The Spaniards invaded the Inca Empire, South America, in 1532. Painted by Juan B Lepiani. Image: MALI@Wikimedia Commons
Amazingly, despite all this, platinum was once considered worthless - at least in Europe. In fact, it was considered a nuisance by the Spanish when they first discovered it in South America - as a corruption in the alluvial deposits they were earnestly mining and they would quite literally throw it away. It wasn’t until the 1780s that the Spanish realised it might have some value.
Because platinum is essential to so many aspects of our economy, there are concerns about supply meeting demand – particularly as nearly 80% is currently mined in South Africa, which has seen its mining industry repeatedly crippled by strikes in recent years.
Two Rivers platinum mine, South Africa. Image: Wikimedia Commons
Some believe the solution to the issue of supply is space mining, arguing the metal could be found in asteroids.
Others, such as researchers at MIT, are working to create synthetic platinum, using more commonly found materials. Neither approach is guaranteed to work but, given our increasing dependence on this precious metal, we could be more reliant on their success than we realise.