Experiments to obtain new bioproducts based on protein extracts from wet-white leather waste intended for the total or partial replacement of phenol formaldehyde resins in wet finishing of leather

Leather retanning is a key operation in the wet finishing stage, playing a very important role in diversification of assortments, but at the same time using complex chemicals can induce important eco-toxic effects especially in the liquid effluents (residual float). This paper presents some of the achievements related to the expansion of eco-friendly auxiliary product range for wet finishing of leather (filling-retanning) with predominantly natural (protein) components, combined with metal oxides other than Cr2O3 and without phenolic compounds, concomitantly with the leather industry's advance towards circular economy and increasing eco-efficiency. An experimental model was developed for functionalization of collagenic materials obtained by acid hydrolysis of pre-tanned wet-white bovine hide waste in order to obtain new bioproducts intended for the replacement of phenolic compounds for wet finishing of leather (filling-retanning).