Abstract

As a result of the almost impossible demands of the legislator, chrome pollution of wastewater from tanneries is increasingly becoming the number one ecological problem for the tanner. There is no lack of processes using a considerably reduced chrome concentration and guaranteeing an acceptable exhaustion of residual chrome liquors. In spite of all ecological and economical advantages of low-chrome tanning, the main objective of the tanner is still to produce high quality saleable leathers. He requires processes which neither complicate the production sequence nor impair the quality of the leather. In the following, a new high exhaustion process, the CrAB. tanning process, is introduced which, at a chrome oxide concentration of 1.3% (calculated on pickled weight) and with a total exhaustion of the chrome tanning liquors, supplies leathers of excellent quality.