The Limonene Biorefinery: From Extractive Technologies to Its Catalytic Upgrading into p-Cymene

Limonene is a renewable cyclic monoterpene that easily obtainable from citrus peel and it commonly used as nutraceutical ingredient, antibacterial, biopesticide green extraction solvent well additive in healthcare, fragrance food beverage industries for its characteristic lemon-like smell. Indeed, the lack of toxicity makes limonene promising bio-alternative development wide range effective products modern biorefineries. As consequence, industrial demand largely exceeds supply by now. can be also starting substrate preparation building block chemicals, including p-cymene an important intermediate several catalytic processes. In this contribution, after reviewing recent advances recovery residues with particular attention to benign-by-design extractive processes, we focus on latest results dehydrogenation via heterogeneous catalysis. reports evidence selective production still remains scientific technological challenge since, order drive isomerization limonene, optimal balance between catalyst nature/content reaction conditions needed.