Used Christmas Trees Can Skip Landfills And Be Turned Into Bio-Oil

In a recent study, researchers at the University of Sheffield and the University of Valladolid have found that pine needles from used, discarded Christmas trees could be transformed into eco-friendly chemicals, which would help reduce the holiday season’s carbon footprint. 

Published in ACS Sustainable Chemistry & Engineering, the findings showed that pine needles could have a second life as value-added chemicals, such as preservatives used in agriculture, where only water would be needed as a solvent. 

An estimated six to eight million live Christmas trees are sold in the United Kingdom annually, with most of them ending up in landfill at the end of the festivities. Aside from being wasteful, each tree releases 16 kg (35 lbs) of greenhouse gases as it decomposes, including the potent methane gas.

As such, scientists build upon previous research conducted in 2018 that found these leftover pine needles could be made into useful products. 

Just by adding heat and solvents, the chemical structure of the needles can be broken down into bio-oil, which features in items like paint, sweeteners, adhesives, and vinegar.

This time, the team realized that by reacting carbon dioxide with pine needles and water at a high temperature, a fraction of the leaves turned into the same product as the gas—sodium bicarbonate, or more commonly known as baking soda. 

It appears the co-conversion together with the carbon dioxide speeds up the conversion, allowing for a more efficient way to create formic acid as the end product. This then can be used in fuel cells to store and transport renewable fuels such as hydrogen, an eco-friendly power source.

In addition, formic acid can be used as a preservative for foods or as an antibacterial agent in livestock feed. When Christmas trees aren’t filling up the landfills, the team posited different waste materials could have the same effect, such as sugar cane. 

Could this be the ingenious way to reduce the amount of biomass waste entering landfills after Christmas each year? Well, if it does save the estimated 100,000 tonnes of greenhouse gases being released into the air, it’s definitely one to try out.

[via University of Sheffield, cover image via Aprescindere | Dreamstime.com]