Keratin hydrolysate as a foaming auxiliary for textile dyeing process

AbstractKeratins are fibrous proteins which are the main constituent of wool fibres. Keratins are abundantlyavailable in nature and also available as by-product from wool industries, horn and hooves fromslaughterhouse, feathers from poultry, animal hair from tanneries. [1] Keratin, due to its naturalabundance, has found various applications-such as insulation pads, animal feed, chelating agents etc.[2] Proteins are similar to the amphiphilic synthetic surfactants, because they are composed of bothhydrophobic and hydrophilic amino acids that afford them a certain degree of surface activity [3]. Thepurpose of this work is to understand the impact of superheated water hydrolysis on the foamingbehavior of keratin hydrolysates, in relation with their applications in textile dyeing. The effect ofhydrolysis temperature and the concentration on wool were investigated. Superheated water hydrolysiswas carried out in small lab scale rector at temperatures of 130-180 °C, with a material liquor ratio of1:3-5, for 1 h, to achieve complete solublization of wool in water. The keratin hydrolysate obtainedafter the hydrolytic treatment consist of polypeptide chains of variable length, which are naturaloligomeric surfactants, and can be applied as potential textile auxiliary and can be used as effectivefoaming agent in textile foam dyeing process. In the investigated variant, hydrolysis is an ecofriendlyprocess in terms of conservation of water, chemicals, and less load on waste water treatments. Keratinhydrolysates are easily biodegradable, and the foam dyeing technology is less adds on technology,resulting in saving of large amounts of water and energy.