The benefits of Circulose
One of the biggest recent stories in the sustainable and circular fashion space was the announcement by H&M group of a new sustainable fibre called “Circulose” in their collections, which is a viscose fibre made with 50% cotton waste.
In order to explain this material, we need to say that circulose is a viscose that belongs to a family of fibres called rayons, which are man-made cellulosic fibres. These are fibres formed by the chemical processing of cellulose, a biological material which is found in nature in wood, cotton and most plants.
Any viscose fibre is traditionally made using cellulose extracted from wood, with a two step process. The first step is turning the wood into pulp with a mixture of chemicals, to remove the unwanted portions of the material. The second step is the process of turning this pulp into a fibre through a process called the viscose process, which involves a chemical reaction of cellulose pulp first with sodium hydroxide, then with carbon disulphide. This mixture is then ejected into an acidic water bath which removes the chemicals leaving behind a pure cellulose fibre. This fibre generally has a smoother, shinier feel compared to cotton, which is also made of cellulose and has the potential to be used in the viscose process as well as having the potential to solve the issue of recycling unwanted cotton.
Re:newcell is a Swedish company which was formed with the aim to commercialise a process for decomposing cellulose to unlock the recycling of waste cotton at scale. The company’s main product has been branded ‘Circulose’ and it is an alternative cellulose pulp that is used for making rayon fibres, such as viscose. It is made by taking cotton waste and purifying it with a water-based chemical process to remove dyes and other contaminants. The properties of cellulose are also altered enough that it is suitable as a feedstock for the production of these rayon fibres.
Circulose is being associated with sustainability as it provides a viable end-of-use pathway for waste cotton, as well as being a fibre that has a much lower carbon emission impact when compared to viscose fibres made from wood pulp. The substitution of a raw material with a recycled material is associated with positive environmental benefits. The logging, further processing and chemical breakdown of wood to make pulp uses energy and has an associated carbon footprint. When using waste cotton as an input, you already start with a cellulose based raw material, which doesn’t require as extensive processing to get to a fibre. On top of that, there’s another associated issue with the production of viscose fibres, especially in East and South East Asia, which is the danger of sourcing wood from ancient or endangered forests. By reducing reliance on wood as a feedstock this danger can be reduced.
When you recycle a material that has the potential to offset a ‘virgin’ and non recycled material, the saving in carbon emissions between the recycled material produced and the virgin material can be significant. In this case, the recycled ‘Circulose’ pulp replaces the wood pulp raw material making the process’ carbon emissions impressively small. A study commissioned by Stella McCartney even found that the production of viscose fibre using recycled cotton from the re:newcell process actually resulted in a net reduction in overall carbon emissions. Another factor to consider is that with re:newcell being based in Europe where the percentage of renewable energy in the mix is greater and regulation over chemical processes are stricter, making the overall environmental impact of viscose fibres made in Europe a lot less than in some places in Asia.
H&M was the first brand that partnered up with re:newcell to become the first brand to begin using their proprietary sustainable fibre Circulose. Nowadays, three of the brands from the danish fashion retailer Bestseller started to produce garments using Circulose too. H&M not only has adopted a percentage of Circulose in part of their collections but has also accelerated this partnership by investing in re:newcell back in 2017. Although this investment from the Fashion brand has been criticised and accused of ‘greenwashing’, the company doesn’t own the rights to the material. Infact, other Fashion brands are still free to invest or collaborate with re:newcell for their future collections.
[Information sourced on thecircularlaboratory.com and eco–rebels.com
Featured image by Vishal Banik on Unsplash
Image 1 by Sze Yin Chan on Unsplash
Image 2 by Janko Ferlič on Unsplash]