InKa: Intermediates from industrial spent coffee grouds

Recycling possibilities for waste from instant coffee production


The "InKa" project develops and evaluates recycling options for spent coffee grounds from the catering and commercial sectors.

Spent coffee grounds as a raw material source

The spent coffee grounds are firstly proceeded to high quality intermediates which can then be used to produce additives for plastics and different types of paper.

Project objectives: development and evaluation of recycling options for spent coffee grounds

The production of instant coffee creates wet spent coffee grounds as a major by-product, which up to now has only been used as a source for renewable energy on industrial scale. In the EU alone, available spent coffee grounds amounts to about one million tons per year. In order to make this matter usable in a material way, the "InKa" project will develop and evaluate recycling options for spent coffee grounds from the catering and commercial sectors within a timeframe of three years.

Project benefits: Conversion of coffee grounds into high-quality intermediates

Coffee is the second most important commodity after crude oil and its commercial importance is steadily growing. The large amount of residual material produced during the manufacture of the beverage is moist spent coffee grounds, which can hardly be collected from private households due to rapid mold growth. However, high-quality recycling approaches exist for spent coffee grounds from the catering and commercial sectors, but these have so far faced significant market barriers.

The aim of the project is to develop a industrially scalable approach for converting commercially available spent coffee grounds into high-quality intermediates. A special focus is set on the fact that these intermediates not only represent a raw material for biobased products, but also lead to previously unattainable improvements in the properties of the end products or replace other, less available raw materials.

Development steps and scale-up

As a first step in the overall process chain coffee oil is extracted from spent coffee grounds with a solvent. The recovered coffee oil is transesterified with an alcohol to fatty acid alkyl esters and subsequently fractionated. The fraction with a high C18:2 alkyl ester is catalytically converted to a plastic additive.  The de-oiled spent coffee grounds are used as innovative additive for papers and paperboards. An overreaching material flow analysis of all process steps delivers a cost indication for intermediate and final products.

As always, the scale-up of a process from the laboratory to industrial production poses one of the challenges to be tackled. The envisioned process chain as a whole is highly innovative and provides an important contribution to the use of bio-based raw materials in the bioeconomy.

Project partners

  • BellePapier GmbH
Associated partners
  • Deutsche Extrakt Kaffee GmbH
  • Kartonfabrik Kaierde GmbH Co. KG
  • Gebr. Grünewald GmbH & Co. KG
  • Hakle GmbH
  • Mondi Uncoated Fine & Kraft Paper GmbH
  • Papier-und Kartonfabrik Varel GmbH & Co.KG

Duration: May 2019 until May 2022