Objectif The possibility of using colloidal silicas of small size in the leathermaking process has been demonstrated. A new ecological white stabilized intermediate (WSI) for tanneries has been developed, obtained through new types of colloidal silicas with very small diameter (between 6 and 10 nm). Four molecules have given good results. The main achievement at the end of the project was production at the industrial level of 4 stable colloidal silicas adapted to the WSI specifications. The WSIs obtained with these molecules through the different processes developed in this research have allowed: the selection of the mechanical operations before tanning, allowing the choice in quality and thickness and the best adapted tanning process; one year preservation for the WSI; development of 3 new direct tanning processes: direct velvet, direct white and direct chromium, based on WSI; great quality improvements in the final leather produced; drastic reduction of the chrome pollution to comply with new European regulations; reduction of around 25% of the chemicals used; reduction of the labour cost of around 30%; the recycling of the wastes (nontoxic, since the colloidal silicas are food authorized) for the production of collagen hydrolysates for the food, pharmaceutical and cosmetics industries; a general saving for the tannery fixed at a conservative 30% compared with the classic wet blue process. Champ scientifique engineering and technologyenvironmental engineeringwaste managementwaste treatment processesrecyclingnatural scienceschemical sciencesinorganic chemistrytransition metalsnatural sciencesearth and related environmental sciencesenvironmental sciencespollution Programme(s) FP2-BRITE/EURAM 1 - Specific research and technological development programme (EEC) in the fields of industrial manufacturing technologies and advanced materials applications (BRITE/EURAM), 1989-1992 Thème(s) Data not available Appel à propositions Data not available Régime de financement Data not available Coordinateur Société Française Hoechst Contribution de l’UE Aucune donnée Adresse Tour Roussel Hoechst 92080 Paris la Défense France Voir sur la carte Coût total Aucune donnée Participants (2) Trier par ordre alphabétique Trier par contribution de l’UE Tout développer Tout réduire Deutsche Gelatine-Fabriken Stoss AG Allemagne Contribution de l’UE Aucune donnée Adresse Gammelsbacher Straße 2 6930 EBERBACH Voir sur la carte Coût total Aucune donnée Società per Azioni Lavorazione Pelli Italie Contribution de l’UE Aucune donnée Adresse Corso Torino 155 10086 Rivarolo Canavese Torino Voir sur la carte Coût total Aucune donnée