The idea is to convert lignin (low cost material) in different chemicals (high value and biosustainable) by means electricity in an electrochemical reactor.

Project

Three electrochemical processes were evaluated in the project, each one with different starting materials and products.

The vanillin phenolic process was validated at TRL 6 with the construction and demonstration of an electrochemical pilot plant at SINTEF for the production of vanillin and phenolic mixtures from kraft or organosolv lignin thanks to the oxidizer PODIC and a yield of 8 % of vanillin was achieved. The phenolic mixture was evaluated by Chimar for the production of phenol formaldehyde adhesives and by Oxiris as antioxidants. Vanillin was evaluated by Perstorp for the production of different vanillin derivatives.

The 3-propyl adipic acid (3PAA) process was validated at TRL 5 with demonstration of an electrochemical bench scale reactor at JGU for the production of 3PAA from propylcyclohexanol. A yield of 48 % of 3PAA was achieved and the produced material was evaluated by Megara for the production of unsaturated polyester resins and saturated polyester resins for powder coatings and by Evonik for the synthesis of lignin-derived dicarboxylic acids and polyamide.

The direct electrochemical degradation process of organosolv lignin was validated at TRL 4 with the process validation at the University of Alicante for the production of phenolic mixtures. Different separation techniques were evaluated and 80 % of yield was achieved.

Objectives

The main technical objectives of the project and the achieved values at the end of the project are:

  1. Electrochemical depolymerisation of kraft lignin to synthesise vanillin with a 7% yield. ➡️ 8 % yield of vanillin was achieved
  2. Electrochemical depolymerisation of organosolv lignin to synthesise mixed phenolic derivate oligomers with a yield of > 35%  ➡️80 % yield of phenolic derivate was achieved 
  3. Electrochemical oxidation of biosustainable cyclohexanol derivatives to synthesise propyl adipic acid with a yield of up to 80%. ➡️ 48 % yield of propyl adipic acid was achieved
  4. A biorefinery process:
  • Renewable energy fluctuations without loss in efficiency ➡️ achieved
  • 30 % improvement in the energy  efficiency of the process ➡️ improved at least 37 % was achieved
  • 30 % improvement resource efficiency ➡️ increased by at least 35 % was achieved
  • 40 % reduction in CO2 emissions ➡️ 97 % reduction was achieved

Value chain