Definition of the toxic products in the tanning process
Completed the definition of the toxic products in the tanning process at the bating, defatting, tanning, fatting and dyeing stages in order to evaluate which products should be removed from the tanning process formulations and to find information on potential natural substitutes less dangerous and polluting.
Main environmental impact and hazardous substances in the tanning process
TANNING STAGE |
TRADITIONAL PRODUCT |
ENVIRONMENTAL IMPACT |
Bating |
Enzymatic products |
Presence of ammonium in wastewater |
Defatting |
Alkylphenol and alkylphenol ethoxilates |
Restricted substances (EU regulations) |
Tanning |
Chromium salts/ Chromium VI |
Restricted substances (EU regulations) |
Dyeing |
Azocolorants and azodyes Acid dyes mixed with surfactants, dispersing agents, paraffin, inorganic salts, etc. |
Restricted substances (EU regulations) Increase of conductivity and non-biodegradable organic load in wastewater |
Fatting |
Chlorinated paraffins short chain (C10-C13) |
Restricted substances (EU regulations) |