Raw material selection for biobased additives
The focus here is on utilizing hitherto unexploited plant-based raw materials and waste materials from the food and agricultural industries.
Biobased additives can be used in many technical products to replace fossil-based materials. Potential applications include bio-based antioxidants, corrosion inhibitors, friction-reducing agents, and anti-abrasion additives for lubricants, coatings, and adhesives. The additives are manufactured from high-functionality proteins and secondary plant substances (SPSs) found in nature. The functionality of the additives can be influenced by customized selection of the raw materials.
In order to isolate different classes of SPSs we design effective extraction processes for different raw materials and waste materials. We focus on utilizing byproduct streams from the food and agricultural industries that up until now have not been exploited. We subsequently develop model water-based, solvent-based, or oil-based formulations in order to make the secondary plant substances soluble in different liquid media.
As part of the development work we study the additive functionality and interactions with other components of the formulations. All stages of the development work, from the recovery of the SPSs to the manufacture of application-ready formulations containing biobased additives, can be carried out at the Fraunhofer IVV. Work can be conducted on a laboratory scale right up to small pilot plant quantities.
Many plant-based waste materials from the food and agricultural industries contain high quantities of functional ingredients such as proteins and SPSs (secondary plant substances). These include residues from processing fruit (e.g. apple pomace) and vegetables (e.g. cabbage) and also from plant oil production (e.g. olive and rapeseed press cake) and other plant waste materials.
Using our extensive knowledge of plant raw materials we continually develop and optimize effective methods for the extraction, purification, and stabilization of plant substances. This allows us to recover high-quality plant proteins, plant oils, secondary plant substances, and dietary fiber.
Our objective is to utilize hitherto unused waste material streams to promote the bioeconomy and the holistic usage of materials. Material availability and cost are always considered.
In order to recover the highest yields of plant extracts having the highest possible functionality we specifically tailor the extraction method to the relevant raw material.
Extraction can be carried out with organic solvents and also, particularly effectively, with supercritical CO2. The extractions are performed using percolation and immersion and are carried out in explosion-proof plants. Treatment steps such as filtration, distillation, and concentration are also conducted under explosion-proof conditions.
Samples can be produced in the laboratory and, after scale-up, in our pilot plants in quantities up to 300 liters,with consideration of industrial feasibility.
The successful use of biobased additives requires those substances to be characterized as comprehensively as possible. This includes quantitative and qualitative determination of the composition and evaluation of their physical and functional properties.
Particularly important is testing the properties in the relevant application along with the stability and storage behavior. The target application is studied in detail using advanced chemical and physical analytics. Interactions with other formulation components are also investigated.
In order to optimize the functionality we are able to carry out enzymatic, chemical, and physical modifications.
We evaluate the process options based on the target application and raw material availability. The cost of the processes and their viability for industrial implementation are considered. Lubricants, for example, contain various additives in order to meet the requirements for a specific application.
Plant oils that are already used for bio-lubricants are very susceptible to oxidation and additives are required to enhance stability. Particularly suitable for this application are SPS-rich extracts that are known for their antioxidative properties.
Hydraulic lubricants, for example, largely consist of water and so corrosion protection is essential for formulations. Plant extracts containing secondary plant substances (SPSs) that have anti-corrosion properties due to their chemical structures have the potential here to replace conventional corrosion protection additives. Using combinations of different SPSs is even more effective due to synergistic effects.
It is essential to add anti-abrasion additives that form a protective film on the metal surface. Proteins and SPSs can also be used as biobased friction-reducing agents and anti-abrasion additives in hydrophilic and lipophilic systems.