About INNOBITE

Project Outputs, Progress

INNOBITE PROJECT RESEARCH SUMMARY

After 3 years, the European project, INNOBITE, is coming to an end. The project has aimed to contribute to the development of sustainable consumption and production patterns through the development of new technological solutions based on the efficient use of natural resources, and in this respect was successful. What follows, is a summary of the research undertaken during the project which elaborates on the achievement of the projects aims and objectives.

Raw materials extraction

Lignin, along with the hemicellulose, was successfully extracted from wheat straw using biorefining process technology based on solvents. The remaining solid fraction is delignified later in the process in order to remove residual lignin. Lastly, lignin is separated from hemicellulose using an organic solvent, ready for use in the proceeding stages of the project. The extraction and processing of the wheat straw included a novel refining stage based on an extraction of high purity silica – a process which is currently being patented.

A specialty pulp was produced at pilot scale, initially from thermomechanical pulp (the major newspaper pulp component) and wheat straw pulp through an alternative chemical process. Processing conditions on both chemical and mechanical treatments were optimised over a large number of trials, with the aim of minimising the final MFC production cost, with special focus on decreasing the energy consumption which was achieved through the use of cavitron equipment. Work was also undertaken to upscale technologies from laboratory to industrial scale, including modifying existing industrial techniques to better suit production of MFC. Under those conditions, despite a high content of impurities, MFC was successfully obtained at lab scale.

Intermediate materials - MFC

Within the INNOBITE project, micro fibrillated cellulose (MFC) was produced from the isolation of virgin thermomechanical pulp and waste resources (recycled newspaper and wheat straw). The production of MFC proved to be viable with a Masuko Supermass Colloider device. However, the mechanical properties of the final material were not as high as expected. The cause could be found in the presence of unknown additives and inks that effect the production and rheological behaviour during isolation. Work is currently ongoing to overcome said challenge. Along the process of obtaining MFC, different tasks were carried out including the characterisation of the material, quality assessments and chemical modifications in order to compatilibise this material with its matrix. Eventually, MFC films with an average size of 10x15 cm were prepared in anticipation of preparation of a thermosetting composite panel. The reinforcing ability for resins with MFC blend were demonstrated, although the blending and solvent casting process did not match the up-scaling requirements.

Figures - From left to right: Masuko grinder equipment, MFC produced from recycled newspaper (NP) and from wheat straw (WS).

 

Figure -MFC films

 

Intermediate materials – LTP resin using biolignin

In addition to the developed silica LTP resin, production of ARBOFORM® L-TP resin, based on biolignin derived from wheat straw (instead of Kraft lignin), was optimised during the INNOBITE project. The optimisation considered: Material properties (mechanical, thermal, …), Process technology (feeding, compounding, degassing, pelletizing, …), Economic issues (Raw materials prices, setup costs, throughput, …), Security of supply (raw materials, spare parts, …), Screw design, Feeding technology, Pelletising process and Venting and degassing.

Figure -Compounding process at TECNARO

The resin, based on wheat straw lignin obtained in the INNOBITE project, had several advantages over the same ARBOFORM grade which utilises lignin from the Kraft process. Advantages of this material are:

  • Less sensitivity to shear and heat
  • Less tendency to produce incrustractions (suitable especially for compounds intended for extrusion)
  • Impact on the mechanical properties
  • Availability of biolignin at acceptable prices

Intermediate materials -Lignin based resins (L-TS)

Formulations of lignin-epoxy -composed of wheat straw lignin and the epoxy prepolymer, mixed later with the amine hardener we produced. The amount of lignin in epoxy resins had a significant impact with small quantities addition makes drastic impacts on the stress and strain.

Formulations of lignin-epoxy -composed of wheat straw lignin and the epoxy prepolymer, mixed later with the amine hardener we produced. The amount of lignin in epoxy resins had a significant impact with small quantities addition makes drastic impacts on the stress and strain.

The developed material meets some requirements, such as processing viability, mechanical performance and bio-based content. The final result has been a 10 % lignin-epoxy formulation system, which shows a good processability and a high biobased content together with an excellent mechanical properties.

Figure -10% wt lignin content resin

Products - LTS+MFC composites – indoor panel

A Biocomposite panel made with L-TS resin and MFC was produced. The produced bio-composite acts as te skin of a honeycomb paperboard yielding a sandwich panel. The required processing method varied according to desired product. Flat pieces were made by manual lamination (Hand Lay-up) which could have variations such as the application of vacuum during the curing process removing the excess resins and air entrainment.

Figure -INNOBITE prototype indoor panel

Products –WPC for decking and fencing applications.

Pipe profiles with 5 cm diameter were produced during extrusion trials of Lignin thermoplastics. Coextruded profiles with both biolignin based cellulose fiber/L-TP and silica/L-TP compounds in the inner layer are expected to meet the INNOBITE objectives and technical specifications for applications in decking or fencing.

Thermoplastic lignin based composite profiles