Novel Heterogeneous Catalyzed Pathways for the Production of trans,trans-Muconic acid

 Muconic acid (MA) is a value-added product with conjugated diene and di-acid groups. Its growing visibility is due to its potential as starting material or versatile monomer for synthesizing value-added derivatives (adipic acid, terephthalic acid, …) or specialty polymers. Owing to diene functionality, three isomers of MA are present, namely cis,cis-MA, cis,trans-MA, and trans,trans-MA. Existent biotechnological technologies only produce the first two isomers, however, the value-added ttMA is the desired form, since it owns the unique potential of being used in the production of terephthalic acid (Diels-Alder chemistry) and specialty polymers. So how to get to the trans,trans form? In this project, we propose two heterogeneous catalyzed processes. The first studies the isomerization of ccMA into ttMA by rutheniumzeolite catalysts (minor loading), that show good activity in the isomerization of fatty acids. After accessing to kinetic and thermodynamic constants, the isomerization mechanism will be investigated, via collaboration (Technical University of Denmark), using a well-adapted in-situ NMR study. The second process uses deoxydehydration DODH reactions to produce ttMA from gluconic acid. Existing DODH systems mainly use homogeneous catalysts and sacrificial hydrogen transfer agents as catalyst healers. Our goal will be to build an upgraded process with a heterogeneous aspect in which gluconic acid will heal the catalysts during its transformation into the desired ttMA.