The use of non-chrome mineral tanning materials as a preferable environmentally friendly tanning material

Mineral chrome tanning agent is the most widely used tanning agent for various types of leather articles, given its various advantages. Besides its many advantages, there is a negative side to chrome tanneries, namely the presence of waste disposal that is harmful to the environment. Therefore, this study aims to determine the quality of mineral tanning materials other than chrome (aluminium and titanium) as a substitute for leather tanning (free of chrome). The research raw materials were 12 pieces of pickled goatskin. The chemicals used are aluminium tanning agent (Novaltan Al), titanium tanning agent, salt (NaCl), Peramit MLN, Derminol OCS, MgO, NaHCO3, BCG indicator, Rellugan GT 50, Tanigan PAK, Lipoderm Liquor SAF, Dermagen GPA, Derminol SPE, Derminol NLM, Acid dyestuff, formic acid, Sincal DR and anti-fungal. The method used is to carry out the tanning process using aluminium tanning agents with levels of 2%, 4%, and 6% Al2O3, continued the combination between aluminium and titanium tanning agent. The results obtained were analyzed for the cross-sectional and content of the leather using the EDX method, a shrinkage temperature (Ts) test, and physical quality of crust skin. The results showed that the higher the Al2O3 content, the more Al content in the leather, but the lower the wrinkle temperature of the leather. Meanwhile, the longer the processing time, the aluminium content in the skin increases. The use of aluminium and titanium tanning agent can improve the physical quality of the skin, both in terms of tensile strength and skin softness. The conclusion that can be drawn is the use of 2% free of chrome (aluminium) tanning material can produce Ts of 71°C. The physical quality of the crust skin from aluminium and titanium mineral tanning agents is better than the single-use of aluminium.