Novel Way of Transformation of Tannery Waste to Environmentally Friendly Formaldehyde Scavenger

Collagen is a typical amphiphilic natural macro-molecule with amino- and carboxylic-end groups and many acidic or alkaline branches. The hydrolysis of collagen will release many hydrophilic functional groups including carboxyl, hydroxyl, amino, etc. These functional groups, especially amino group, car? react with formaldehyde so that collagen-derived polypeptide can be used as natural formaldehyde scavenger. In this study, the collagen-derived polypeptide was extracted from organic phosphonium-tanned leather shavings by using magnesium oxide and alkaline protease with extraction rate as high as 90.4%. To increase the functional groups that reacted with formaldehyde, the extracted collagen-derived polypeptide was modified by diethylene triamine; characterization by FTIR, GPC, and H-1 NMR suggested that the content of amino group increased. Moreover, the amount of formaldehyde removed by The modified collagen-derived polypeptide, i.e., the aminated collagen-derived polypeptide, was significantly increased to 94.7% comparing with that by using collagen-derived polypeptide with the dosage of 70 mL/m(3), respectively. Therefore, modifying the hydrolysate obtained from the leather shavings and using as the formaldehyde scavenger has a good potential in achieving the benign treatment and reuse of the solid leather wastes. (C) 2008 American Institute of Chemical Engineers Environ Prog, 28: 285-290, 2009