Dehairing Enzymes

Enzymatic Dehairing in tanneries has been envisaged as an alternative to Sulfides. Tanneries are constantly concerned about the obnoxious odor and pollution caused by the extremely toxic sodium sulfide used in the Dehairing process step. Deaths due to this toxic chemical process have even been reported. Worldwide, it is estimated that 315 million bovine leathers are produced per year. Considering a waste treatment cost of $0.30 per m2 of leather produced, more than $1 million is spent per day to treat the waste from tanneries around the world. We report here a novel keratinase from Bacillus subtilis that has the potential to replace sodium sulfide in the Dehairing process.

Hides and skins have hair attached to them that must be removed for their use as leather. The conventional way to remove hair from hides is to use harsh chemicals such as lime and sodium sulfide. These chemicals completely dissolve the hair and open up the fiber structure. With enzyme-assisted Dehairing, it is possible to reduce the chemical requirements and obtain a cleaner product and a higher area yield with fewer chemicals in the wastewater. Since the enzyme does not dissolve the hair as the chemicals do, it is possible to filter out the hair, thus reducing the chemical and biological oxygen demand of the wastewater.

AETL offers ECODEHAIR for Dehairing of hides and skin.