Tanning procedure with high chromium suction from the tanning bath

摘要

The efficiency of chromium utilization in chrome tanning of hides to make leather is greatly improved by performing the preliminary neutralization of the acid tanning liquor in the presence of an aldehydo or keto acid, before conventional subsequent neutralization with an alkali aluminum silicate. Most preferably, a combination of glyoxylic acid and magnesium oxide is used for the preliminary neutralization.