LONDON: Abandoned Christmas trees could be saved from the landfill and turned into paint and food sweeteners, according to a study.
Christmas trees have hundreds of thousands of pine needles which take a long time to decompose compared to other tree leaves, said researchers from the University of Sheffield in the UK.
When they rot, they emit huge quantities of greenhouse gases which then contribute to the carbon footprint.
The study by Cynthia Kartey, a PhD student at the University of Sheffield, found that useful products can be made from the chemicals extracted from pine needles when processed.
The major component (up to 85 per cent) of pine needles is a complex polymer known as lignocellulose.
The complexity of this polymer makes using pine needles as a product for biomass energy unattractive and useless to most industrial processes.
"My research has been focused on the breakdown of this complex structure into simple, high-valued industrial chemical feedstocks such as sugars and phenolics, which are used in products like household cleaners and mouthwash," Kartey said.
"Biorefineries would be able to use a relatively simple but unexplored process to break down the pine needles," Kartey said.
With the aid of heat and solvents such as glycerol, which is cheap and environmentally friendly, the chemical structure of pine needles is broken down into a liquid product (bio-oil) and a solid by-product (biochar).
The bio-oil typically contains glucose, acetic acid and phenol.
These chemicals are used in many industries -- glucose in the production of sweeteners for food, acetic acid for making paint, adhesives and even vinegar.
The process is sustainable and creates zero waste as the solid by-product can be useful too in other industrial chemical processes, researchers said.
Fresh trees and older, abandoned Christmas trees can both be used, they said.
"In the future, the tree that decorated your house over the festive period could be turned into paint to decorate your house once again," Kartey said.
The UK uses as many as 8 million natural Christmas trees during the festive period every year and about 7 million trees end up in the landfill, researchers said.
If pine needles were collected after Christmas and processed in this way, the chemicals could be used to replace less sustainable chemicals currently used in industry, they said.