Greener approach to leather tanning process: d-Lysine aldehyde as novel tanning agent for chrome-free tanning

► The d-Lysine GTA improves conventional tanning and exhibits lowest chemical cost. ► Reduction of solid and liquid wastes, BOD, TS, DS and SS loads were achieved. ► Improves the hydrothermal stabilities via intra and inter molecular crosslink. ► The tanned leather revealed a properly oriented and well aligned fibre structures. ► Creates new topologies inaccessible to homochiral and yield proteolytically stable.