It is approximated that 25 million tons of cotton textiles are discarded around the world every year. When you add up the different types, an overall of 100 million tons of textiles are thrown out.
” Considering that cotton is a sustainable resource, this is not particularly energy-efficient,” says Edvin Ruuth, a scientist in chemical engineering at Lund University.
” Some fabrics still have such strong fibers that they can be re-used. This is done today and might be done a lot more in the future. A lot of the material that is disposed of has fibers that are too short for re-use, and faster or later on all cotton fibers become too short for the procedure understood as fiber regeneration.”
Where Edvin Ruuth works, at the Department of Chemical Engineering in Lund, there is a lot of accumulated knowledge about utilizing enzymes and micro-organisms, among other things, to change the “harder” carbohydrates in biomass into simpler particles. This suggests that whatever from biological waste and black liquor to straw and wood chips can end up being bioethanol, biogas, and chemicals.
Now the researchers have actually also succeeded in breaking down the plant fiber in cotton– the cellulose– into smaller components. However, no microbes or enzymes are involved this time; instead, the process involves soaking the fabrics in sulphuric acid. The result is a clear, dark, amber-colored sugar solution.
” The secret is to find the right combination of temperature and sulphuric acid concentration,” explains Ruuth, who fine-tuned the dish together with doctoral student Miguel Sanchis-Sebastiá and professor Ola Wallberg.
Glucose is an extremely flexible molecule and has numerous possible uses, according to Ruuth.
” Our strategy is to produce chemicals which in turn can become numerous types of textiles, consisting of spandex and nylon. An alternative usage could be to produce ethanol.”
From a typical sheet, they extract 5 liters of sugar solution, with each liter including the equivalent of 33 sugar cubes. Nevertheless, you couldnt turn the liquid into a soft drink as it likewise contains corrosive sulphuric acid.
Among the difficulties is to conquer the complex structure of cotton cellulose.
” What makes cotton special is that its cellulose has a high crystallinity. This makes it hard to break down the chemicals and recycle their elements. In addition, there are a great deal of surface treatment compounds, dyes, and other toxins which must be eliminated. And structurally, a terrycloth towel and an old pair of jeans are really different,” says Ruuth.
” Thus it is an extremely delicate procedure to find the best concentration of acid, the ideal number of treatment phases, and temperature.”
The concept of hydrolizing pure cotton is nothing new per se, explains Ruuth; it was found in the 1800s. The trouble has actually been to make the procedure effective, economically practical, and attractive.
” Many people who attempted wound up not making use of much of the cotton, while others did much better but at an unsustainable cost and environmental impact,” states Ruuth.
When he started making glucose out of materials a year ago, the return was a paltry 3 to four percent. Now he and his associates have actually reached as much as 90 percent.
When the dish formulation is total, it will be both cheap and relatively simple to utilize.
However, for the process to come true, the logistics must work. There is presently no established method of handling and arranging numerous textiles that are not sent out to common clothing donation points.
Thankfully, a recycling center unlike any other in the world is currently under building and construction in Malmö, where clothes is arranged instantly utilizing a sensor. Some clothes will be donated, rags can be used in industry, and textiles with sufficiently coarse fibers can end up being new materials. The rest will go to district heating.
Ideally, the percentage of fabrics going to district heating will be substantially smaller once the innovation from Lund is in place.
Recommendation: “Novel sustainable options for the fashion business: An approach of chemically recycling waste textiles via acid hydrolysis” by Miguel Sanchis-Sebastiá, Edvin Ruuth, Lars Stigsson, Mats Galbe and Ola Wallberg, 31 December 2020, Waste Management.DOI: 10.1016/ j.wasman.2020.12.024.
Scientists have actually established a technique that converts cotton into sugar, which can then be turned into spandex, ethanol, or nylon.
A lot of us try to recycle our old textiles, but few people know that they are actually extremely difficult to reuse, and frequently end up in land fills anyway. Now, scientists at Lund University in Sweden have actually established a technique that transforms cotton into sugar, that in turn can be turned into valuable products consisting of ethanol, spandex, and nylon.
It is approximated that 25 million lots of cotton fabrics are discarded around the world every year. A lot of the fabric that is disposed of has fibers that are too short for re-use, and earlier or later on all cotton fibers become too short for the procedure known as fiber regrowth.”
Now the scientists have actually likewise succeeded in breaking down the plant fiber in cotton– the cellulose– into smaller sized elements.” What makes cotton unique is that its cellulose has a high crystallinity. Some clothing will be donated, rags can be used in market, and textiles with sufficiently coarse fibers can become new materials.
