Minimization of the Environmental Impact of Leather Processing: A Benign and Enzyme-based Integrated Leather Processing Technology

Traditional leather processing posed great threat to the environment due to its numerous do-undo procedures and use of tremendous amount of chemicals, especially toxic reagents such as sulfides, lime, ammonium salts, etc. To minimize the pollution loads and avoid using unsafe substances in leather manufacturing, an enzyme-based dehairing and fiber opening, silicate pretreating, liming-deliming-bating free chrome tanning and post-tanning integrated leather processing technology has been achieved using biocatalysts for goatskins under slight basic condition. It has been found that the extent of hair removal, opening up of fiber bundles and shrinkage temperatures of crust leather are comparable to that produced by traditional methods. Scanning electron microscopic analysis, determination of physical-mechanical properties and organoleptic evaluation further verify that performance of the leathers is on par with conventionally processed leathers. Most important is that, reductions in water consumption, wastewater discharge, COD and TS loads are in the order of 60% when compared to conventional leather processing. Thus, the developed leather manufacturing technology offers immense potential for greener production of skins and hides to leather coupled with environmental excellence.