Yibo Ma, Michael Hummel, Herbert Sixta, Aalto University
Upcycling is becoming an increasingly hot topic in our society. It is part of the new bioeconomy concept which promotes the production of value added products with a substantially reduced impact on the environment. Upcycling reduces landfills, harvest of trees, the use of chemicals, and the demand of water. In a previous study, we have demonstrated the possibility to spin waste fine paper and pre-treated waste cardboard from an ionic liquid (IL) solution. The spun fibres from both materials showed good properties and great potential to be applied as textile and technical fibre. The success story encouraged us to move forward: why don’t we try newsprint?
The renowned Finnish newsprint Helsingin Sanomat was selected as raw material which consists of softwood TMP pulp. After a deinking pretreatment the newsprint was subjected to conventional kraft cooking at various H-factors to identify the threshold lignin content that would allow for spinning of the respective IL-solution. The DP of the pulps was adjusted by electron beam irradiation. Dope preparation and spinning were carried out according to the Ioncell-F process protocol. The performance of spinning increased as the cooking intensity enhanced. The fibers showed a unique dark brown exterior with a shiny appearance.
Using newsprint as raw material for cellulosic fiber spinning opens up new possibilities to upgrade waste material to high-value added products. However, to fulfil the concept of sustainability, a greener and more efficient pretreatment method has to be applied which is already in the development pipeline (GVL fractionation). Fibres spun from newsprint are suitable for textile application, bio-composites applications and other technical fibres.