Academic reveals top ten items threatened by CO2



Writing in The Conversation, Mercedes Maroto-Valer, assistant deputy principal,  describes the top ten things which could suffer due to a shortage of CO2…

I have found myself in a rather unexpected place over the past few days. For more than two decades, I have been incessantly proclaiming that we produce far too much carbon dioxide (CO2) with the associated risks of global warming. But while ever more is being pumped into the atmosphere, Europe and Mexico are also running out of usable CO2 – as several plants that produce CO2 have closed down for maintenance.

In total, the world consumes about 80m tonnes of CO2 per year. Annual CO2 emissions are currently around 32 billion tonnes, but we have experienced the worst CO2 supply shortage in decades in the UK. Most of the UK's CO2 demand is met as a by-product from the fertiliser industry that generally closes operations during the summer months. We do produce CO2 from many other sources, but despite the development of CO2 capture technologies, these are not deployed at the commercial pace needed to actually be able to use it.

In the UK, the situation has been exacerbated by the current heat wave and pubs running out of beer – precisely in the middle of the football world cup. But is CO2 really that critical to how society functions? The short answer is yes, and here are ten applications that are threatened by a shortage of CO2.

1. Wine - there's been a bit of a panic about running out of beer in the middle of summer. But there are many other applications of CO2 in the drinks industry, such as carbonated soft drinks. But if you are more of a wine drinker or even a connoisseur, you are not home free. CO2 addition is essential for wine making and achieving the perfect fermentation.

2. Food of all kinds - CO2 also has many applications in the food industry, too, from its use in abattoirs and stunning farm animals before slaughter to the preservation of fresh meat in vacuum-sealed packaging. And vegetarians are just as vulnerable, especially crumpet lovers . CO2 is used widely as refrigerant in food retail applications, including many fruits and vegetables. CO2 laser.

3. Lasers - CO2 lasers are one of the most useful and efficient lasers, producing a beam of infrared light. This is not only relevant for Star Wars fans, CO2 lasers have a wide range of applications in industry for cutting, welding, engraving and even 3D printing. What's more, medical CO2 lasers are used in many soft tissue surgical procedures, from removing vocal cysts to face lifts.

4. Fire extinguishers - CO2 is a non-combustible that can be pressurised – hence its ubiquitous use in fire extinguishers. But pressurised CO2 gas is also used in airguns and self-inflating life jackets. CO2 canisters are also sold as a cyclist's best friend for repairing punctures.

5. Decaf coffee – at a certain temperature and pressure (31°C and 73 atmospheres) CO2 becomes a supercritical fluid. That does not mean it is critically dangerous, but rather that it has very unusual and extremely useful properties. For example, it has the density of a liquid, but behaves like a gas. Supercritical CO2 is used as an environmentally friendly solvent for dry cleaning, decaffeinating coffee and in the production of herbal distillates and essential oils, among other things.

6. Refrigerant Dry ice - is simply solid CO2. This can be used in large, well-known applications, such as blast cleaning, food refrigeration and flash freezing, to small scale uses, such as fog machines and wart removal. Dry ice can also be used to preserve the human body until a funeral and is more environmentally friendly than embalming chemicals.

7. Oil - the largest single industrial use of CO2 is for something called "enhanced oil recovery ". Every year, about 50m tonnes of CO2 are injected into oil reservoirs to push out around 20% of the original oil in place. Most of the CO2 used for this application comes from natural CO2 wells.

8. Plants- we know that plants are big consumers of CO2. Through photosynthesis, plants convert CO2 and water into hydrocarbons. But did you know that gardeners artificially increase the levels of CO2 in their greenhouses to promote plant growth? Will we run out of aspirin?

9. Pain killers - CO2 has many pharmaceutical and medical applications, such as for the production of analgesic and anti-inflammatory drugs. For example, CO2 is used in the production of salycilic acid that is the precursor to aspirin. It is also used for the stimulation of breathing when added to oxygen.

10. Aviation fuels - CO2 is used extensively in research labs, as compressed gas, supercritical fluid or dry ice. In the lab where I work, we may not be using food grade CO2, but we are nevertheless affected by the shortage. Our supplier recently communicated to us that they are "no longer accepting routine orders". And this has consequences. For instance, in one of our research projects we use CO2 together with waste biomass to produce aviation fuels.

So, I have come to realise that after all these years talking about CO2 associated with global warming and climate change, I need to change my research narrative.

Let me try this: our research is committed to ensuring that every day you have the CO2 required for you to continue enjoying your lifestyle, from your preferred food and drink to riding your bike or even using a life jacket.