GRETE - Green Chemicals and Technologies for the Wood-to-Textile Value Chain

Tackling the challenges of a sustainable growth through technological innovation

The GRETE project tackles the increased global demand for sustainable textile fibres by offering new technological breakthroughs for the wood-to-textile value chain.

Production and use of man-made cellulosic fibres are estimated to grow steadily in the future, partly as a reaction to sustainability issues related to cotton: although cotton is a renewable resource, its cultivation requires irrigation water, arable land, fertilizers and pesticides that increase its negative environmental impact. On the other hand, the commercial production processes for man-made cellulosic fibres are far from optimal relying on a limited raw material base, solvent systems built on toxic and explosive chemicals, and water-intense finishing treatments.

The GRETE technologies allow to overcome these bottlenecks, improving significantly the existing processes, while opening up for an increased and sustainable production of man-made cellulosic fibres in Europe.

As an alternative to highly himpacting cotton cultivations, sustainably managed wood may offer the raw material supply for a low-impact European textile industry.

PULP SOLVENTS FIBRES

GARMENTS & FURNITURE finishing printing dyeing

finishing dyeing

finishing dyeing

FABRIC YARN

The GRETE results

Currently, the raw material base to produce man-made cellulosic fibres from wood is limited as only highly processed and pure cellulose (dissolving-grade) pulp is used industrially.

GRETE enhances the utilisation of wood biomass from sustainable European sources for the textile industry. Thanks to chemical and enzymatic modification procedures for softwood and hardwood Kraft pulp, a novel raw material for bio-based textiles is made accessible. The use of standard (paper-grade) wood pulp for cellulosic fibre production results in lower environmental impact and reduced production steps.

Novel solvents for cellulose dissolution and regeneration

Novel solvents for cellulose dissolution and regeneration

Textile production and finishing treatments make use of extensive wet processes, this applies also when utilising commercial man-made cellulosic fibres.

With innovative treatments that are applied either to the pulp or at a later stage, the GRETE process creates novel high-quality man-made cellulosic textile fibres with tailored properties enabling water-scarce finishing treatments. This allows for an innovative textile industry that radically decreases its environmental footprint.

Novel raw material base for the textile industry

Novel raw material base for the textile industry

The common solvent systems for commercial man-made cellulosic fibres are far from optimal being based on toxic and explosive chemicals.

In GRETE innovative green chemicals for man-made cellulosic fibres manufacturing are developed that are based on novel liquid salts. The GRETE solvent system increases safety, sustainability and economic viability of a bio-based textile fibres production.

Novel high-quality fibres with tailored properties

Novel raw material base for the textile industry

Strengthening the European bio-based industry by creating new business opportunities

The technologies defined in the GRETE project widen the raw material base for man-made cellulosic fibres manufacturing while increasing safety and economic viability of a sustainable wood-to-textile value chain. The industrial exploitation of the achieved results is expected to happen throughout the next decade.

VTT Technical Research Centre of Finland (FI) - Coordinator

University of Helsinki, Department of Chemistry (FI)

University of Natural Resources and Life Sciences BOKU (AT)

University of Aveiro (PT)

Metsä Spring - Metsä Group (FI)

CELBI Celulose Beira Industrial - Altri Group (PT)

Materially Impresa Sociale (IT)

BETA Technological Centre UVic-UCC (ES)

The GRETE green chemicals and technologies increase safety, sustainability and economic viability of the European bio-based textile fibre production.

GRETE project has received funding from the Bio-based Industries Joint Undertaking (JU) under the European Union’s Horizon 2020 research and innovation programme.

The GRETE project supports the strategic orientations of the bio-based industry and contributes to the European Commission’s objectives to develop a more resource efficient and sustainable low carbon economy.

International collaboration of excellence connecting Europe’s North and South

The GRETE project is implemented by a consortium of 8 partners, connecting 5 European countries: Finland, Austria, Italy, Spain and Portugal.

The consortium is characterised by a mixture of institutions with complementary competences, being anchored in various fields of activity such as research, consultancy and industry.

OVERCOMING THE BOTTLENECKS OF THE WOOD-TO-TEXTILE VALUE CHAIN

Today, the textile industry is one of the most polluting industries globally, and the demand for textile fibres is estimated to nearly double by 2030 due to population growth.

A way to minimise the environmental footprint of the current textile value chain is to reconsider the raw materials used in the first place: man-made fibres based on natural polymers are a valuable alternative to fossil-based synthetic fibres and controversially sourced natural fibres. Accessing wood pulp, especially paper-grade pulp as a raw material for man-made cellulosic fibres may open up the current bottlenecks and enable a sustainable textile industry.

Pulp manufacturing is already a highly competitive and sustainable bio-based industry that can be found both, in the North and the South of Europe. Combining novel cellulose-based textile manufacturing with such a solid platform is a key element in re-introducing extensive European man-made cellulosic fibre production.

The GRETE technologies enlarge the product portfolio and business opportunities for advanced biorefineries that source their biomass sustainably, prospecting to increase economic growth and employment by developing sustainable and competitive bio-based industries in Europe.

201905

PRE-TREATMENTS

UNIQUE PULP MODIFICATIONS

Nowadays the textile industry uses dissolving pulp to produce man-made cellulosic textile fibres. Replacing this high-grade cellulose pulp with a paper-grade Kraft pulp decreases environmental impact and production expenses.

In GRETE chemical modification and enzymatic pre-treatments of the wood pulp prior to dissolution were carried out, both at high and low pulp consistency, and have enabled the successful spinning of regenerated fibres from hardwood and softwood Kraft pulp. In particular, chemical modifications targeting improved technical properties of the regenerated fibres have been performed, while novel hydrolytic and oxidative enzymes for targeted studies on pulp modification have been developed and used to prepare samples for dissolution studies.

Finally, dissolution and regeneration of proteins have been studied to examine their potential use in cellulosic fibres.

Thanks to the GRETE research we're able to look at integrating the production of textile fibres into paper pulp production.

Consortium Partner Metsä Spring - Metsä Group

If the paper-grade pathway developed in GRETE will be further explored and scaled up, it will be a true breakthrough for the whole industry.

Consortium Partner Celbi - Altri Group

DISSOLUTION

NOVEL SOLVENT SYSTEM

Man-made cellulosic fibres are regenerated from natural polymers via chemical transformation processes. Today two processes are used commercially, and both use toxic, unstable or explosive solvents.

In GRETE novel superbase ionic liquids have been developed: a system of sustainable and recyclable solvents for cellulose dissolution and fibre regeneration, responding to demanding process- and market requirements. The developed superbase ionic liquids have been produced on a kg scale and found to be harmless, as demonstrated by preliminary toxicity and sustainability assessments.

Essential for the economic viability of the process is the recovery and purification of the superbase ionic liquids from the spinning bath. The GRETE research demonstrated reaching the desired ionic liquid concentration using distillation and reducing the energy demand for diluted solutions with membrane filtration.

202304

SCALE-UP

INDUSTRIAL EXPLOITATION

By the end of the project, a family of novel solvents for cellulose dissolution will be available for industrial scale-up. These novel solvents are chemically stable, recyclable and non-toxic allowing environmentally benign and economically viable pathways for cellulose processing to textile fibres. New information concerning the enzymatic modification of Kraft pulp and recycling of the superbase ionic liquids have been obtained and models to assess technical, economic and environmental aspects of the GRETE concept were defined, paving the way for industrial exploitation of the technologies.

The impact of the achieved results is expected to be seen on industrial level and consumer markets throughout the next decade.

REGENERATION

SUCCESSFUL FIBRE SPINNING

With the GRETE technologies, regenerated cellulose fibres have been successfully spun from two enzymatically and chemically modified pulps - hardwood and softwood Kraft pulp - using the novel superbase ionic liquids.

The chemical modifications have been stable during dissolution and regeneration, and an analysis method to determine the amount of residual ionic liquids in the regenerated fibres has been developed. In particular, characterization of impurities from the dissolution and regeneration process and degradation products of superbase ionic liquids have been analysed using sophisticated analytical tools.

POST-TREATMENTS

HIGH-QUALITY FUNCTIONAL FIBRES

Chemical modification carried out either before or after dissolution and regeneration of wood pulp will bring chemical functionalities to fibres. In GRETE the pulp pre-treatments and the post-modifications of regenerated fibres have been successful to introduce fire-retardant and improved dyeing properties to the fibres, allowing to significantly reduce the use of freshwater in the textile finishing processes.

In view of the GRETE achievements, regenerated wood pulp fibres from the pulp and paper industry can potentially be utilised as textile fibres with good dye uptake capacity that may possibly provide an alternative for dyeing treatments.

2020-08

«Enzymatic treatment of softwood kraft pulp at high and low consistency»

2020-10

«Modelling of Lyocell fibre production and technical analysis of solvent recovery concepts»

2021-09

«Spinning of cellulose fibres from ionic liquid solution»

2022-05

«Physico-chemical characterization of aqueous solutions of superbase ionic liquids with cellulose dissolution capability»

2022-09

«Preconcentration of superbase ionic liquid from aqueous solution by membrane filtration»

2022-09

«From regenerated wood pulp fibers to cationic cellulose: preparation, characterization and dyeing properties»

Results are promising: in the future, there might be man-made fibres with quite high amounts of hemicellulose left.

GRETE Green

chemicals and technologies for the wood-to-textile value chain

The innovative technologies developed in the GRETE project respond to the increasing demand for sustainable textile fibres. Novel modification processes enable a direct use of wood pulp as low-impact raw material, while safe and sustainable solvents are used to dissolve and regenerate cellulose into high-quality textile fibres.

The resulting man-made cellulosic fibres offer tailored functional properties allowing for less water-consuming finishing treatments and a reduced environmental footprint.

This project has received funding from the Bio-based Industries Joint Undertaking (JU) under the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No 837527. The JU receives support from the European Union’s Horizon 2020 research and innovation programme and the Bio-based Industries Consortium.

The contents of this publication reflect only the author's view and the JU is not responsible for any use that may be made of the information it contains.