Biobased Lubricants within a Circular Economy Concept: Utilization of Spent Coffee Grounds as an Alternative Sustainable Feedstock

The economy is gradually transitioning to a circular model that extends resources, reduces waste and requires a great deal of creative thinking. Both established and emerging global economies view waste as a bioresource for our next generation energy, chemicals, or platform molecules and materials. Due to the substantial quantities of food-type waste generated each year worldwide, there is a global social and economic need to re-use, re-cycle and/or re-cover these “losses” under sustainable approaches. Nowadays a growing recognition evolves that the twin problems of waste management and resource depletion can be solved together through the utilization of food waste as a resource, using green and sustainable technologies that can play a significant part in the forthcoming bio-economy era. Coffee is one of the most popular beverages with the consumption continuously increasing and generating huge amounts of solid residues in return. This solid waste after the extraction of the coffee beverage is known as Spent Coffee Grounds (SCG). SCG valorization may be directed towards the production of high added value commodities such as lubricants. The biobased lubricants market has been grown substantially the years before, making it one of the promising bio-sectors with multiple applications. Further evolution of this segment shall be based on the concept that biolubricant don’t just have to be environmentally acceptable but also have to fulfill the targets of the new sustainable development agenda that dictates the protection of natural resources through the increasing exploitation of waste materials under industrial symbiosis notions. In this work the capabilities of materializing SCG as a source for biolubricants is explored, the possible pathways and the product's quality are analyzed while the overall sustainability of the process is discussed.