Decarboxylation\nof Amino Acids to Bioamines over BaHPO<sub>4</sub>‑Buffered\nRu-RuO<sub>2</sub> Catalysts

Waste\nprotein-derived l-lysine was decarboxylated and\nhydrogenated to 1,5-pentanediamine (1,5-PDA) with great potential,\nwhich is an important feedstock for the production of the nylon PA56\nmonomer. In this study, a partially coated Ru-RuO<sub>2</sub>/BaHPO<sub>4</sub> catalyst, with a controlled 26.5% surface Ru<sup>0</sup> species,\nwas developed from the RuO<sub>2</sub>/BaCO<sub>3</sub> precursor\nusing an encapsulation strategy with <i>in situ</i> generated\n1,5-PDA as a gelling agent. As a result, l-lysine was decarboxylated\nand hydrogenated to 1,5-PDA via an intermediate of lysinal, affording\na selectivity of 94.1%, space-time yield of 0.97 g·g<sub>cat</sub><sup>–1</sup>·h<sup>–1</sup>, and TON of 374.6\nat 170 °C. The Ru/RuO<sub>2</sub>-based catalyst demonstrated\nstrong acid and over-reduction resistance, thereby providing a way\nto prepare robust catalysts for the synthesis of a wide range of amines\nfrom waste protein-derived amino acids.