Recent developments in modification of lignin using ionic liquids for the fabrication of advanced materials–A review

We may currently observe an important trend in the search for environmentally friendly renewable resources. Biomass is undoubtedly a source of such material. An especially valuable by-product of the paper industry is lignin – a biopolymer with a unique chemical structure. The controlled activation or modification of lignin can be used to generate components with designed properties. Additionally, lignin can be activated using green solvents – represented by ionic liquids – to generate materials for the design of polymer composites and pro-ecological abrasive materials. Another interesting area of application is active platforms for biosensors. Use has also been made of lignin and its derivatives in the removal of environmentally toxic metals and certain organic compounds (herbicides, phenol and its derivatives, pharmacologically active substances) from wastewater. This review emphasizes recent advances in the use of ionic liquids to dissolve or activate lignin. A significant contribution is represented by the material concerning the design of hybrid systems with the use of lignin treated with ionic liquids. New directions of development in the field are also indicated.