New process could lead to reduction in carbon footprints
University of Sheffield
Abandoned Christmas trees could be saved from landfill and
turned into paint and food sweeteners according to new research by the
University of Sheffield.
Christmas trees have hundreds of thousands of pine needles which
take a long time to decompose compared to other tree leaves.
When they rot, they emit huge quantities of greenhouse gases which then contribute to the carbon footprint of the UK.
When they rot, they emit huge quantities of greenhouse gases which then contribute to the carbon footprint of the UK.
Cynthia Kartey, a PhD student from the University of Sheffield's
Department of Chemical and Biological Engineering, has 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.
Cynthia said: "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.
"Biorefineries would be able to use a relatively simple but
unexplored process to break down the pine needles."
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 (bio-char).
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. Fresh
trees and older, abandoned Christmas trees can both be used.
Cynthia continued: "In the future, the tree that decorated
your house over the festive period could be turned into paint to decorate your
house once again."
The UK uses as many as 8 million natural Christmas trees during
the festive period every year and sadly, about 7 million trees end up in
landfill.
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.
This could lead to a decrease in the UK's carbon footprint by
reducing the UK's dependence on imported artificial plastic-based Christmas
trees and a reduction in the amount of biomass waste going to landfill.
Dr James McGregor, Senior Lecturer in the Department of Chemical
and Biological Engineering said: "The use of biomass -- materials derived
from plants -- to produce fuels and chemicals currently manufactured from
fossil resources will play a key role in the future global economy."
"If we can utilise materials that would otherwise go to
waste in such processes, thereby recycling them, then there are further
benefits."
"In our research group we are currently investigating the
production of valuable products from a variety of organic wastes, including
forestry sources, spent grain from the brewing industry and food waste;
alongside investigating processes for the conversion on carbon dioxide into
useful hydrocarbon compounds"