The MOSAIC consortium aims to develop new and modular precoat cells for the electrochemical synthesis of L-cysteine from slightly soluble L-cystine and establish them for future technical implementations.
As an important amino acid, L-cysteine is a starting material for pharmaceutical applications, in the production of flavors or in peptide synthesis. The starting material for the synthesis of cysteine is its dimer, cystine. Cystine is produced by Wacker Chemie AG in a patented biotechnological process by fermentation. The cystine obtained in this way is natural and vegan, which makes it particularly suitable for use in food or pharmaceutical products.
To convert the cystine obtained in this way into the monomer cysteine, also a WACKER product, an electrochemical reduction is carried out in hydrochloric acid on lead or tin cathodes. Due to the poor solubility of cystine, a high excess of acid is necessary. In addition, high current densities, which are important for a high yield, lead to large quantities of hydrogen as a by-product, which is why the efficiency of the reaction is low.
In order to prevent this, the reduction of cystine in modular precoat cells is to be achieved by saving on strong electrolytes. These electrolyzers, which have so far been little researched, are to be scaled up from laboratory to pilot scale. This will improve the energy efficiency of the reaction, which will sustainably reduce the CO2 balance. Furthermore, the use of metal-free or lead-free electrodes will massively improve the quality of the cysteine obtained. The market presence of WACKER's BIOSOLUTIONS division in L-cystine and L-cysteine, combined with the scientific expertise of Johannes Gutenberg University, means that the knowledge gained can be expected to be quickly transferred to applications.
Coordinator:
Siegfried R. Waldvogel (MPI CEC) siegfried.waldvogel@cec.mpg.de
Stefan Haufe (WACKER) Stefan.Haufe@wacker.com