Study: Christmas tree pine needles can be recycled as paint and sweeteners

New research out of the University of Sheffield has found that pine needles from Christmas trees can be recycled into useful products, including food sweeteners and paint. The new process could help reduce the environmental impact of Christmas trees, which result in needles that take a long time to break down, emitting large amounts of greenhouse gases over time.

Millions of Christmas trees end up in landfills following the end of the holiday season. Compared to other tree leaves, pine needles take a long time to decompose and produce very large quantities of greenhouse gases, making them a significant part of a nation's carbon footprint. Transitioning to reusable trees may not be the best solution, however.

The University of Sheffield's Department of Chemical and Biological Engineering PhD student Cynthia Kartey has developed a new method for processing pine needles from these trees into useful products. Key to the method is lignocellulose, a complex polymer that comprises the primary component in pine needles. That polymer has historically been a barrier to using pine needles in various industries.

The new process involves enviro-friendly and inexpensive solvents like glycerol to break down pine needles into a solid bio-char and liquid bio-oil. The latter contains chemicals that are useful in various industrial processes, such as phenol and glucose, potentially allowing it to be used in the creation of food sweeteners, paints, and other common products.

Not only would this process produce useful chemicals, but it could also serve as a sustainable way to get these chemicals, which may otherwise be acquired from less sustainable methods. According to the university, more than 7 million Christmas trees are discarded annually in the UK.