Abstract
This paper presents a model of a chromium-tanning solution used in leather processing. Chromium(III)sulfate is used in leather processes as a tanning agent. This model provides a quick and easy way of determining Cr(III) content in a tanning process having high chromium concentrations. Shifts of absorption peaks and changes in the intensity of absorption—due to different ligands of the chromium complex, aging, or differences in pH and temperature—all create difficulties in the modeling of a chromium-tanning solution. Different multilinear and factor-based regression methods were applied, and the results were compared. The influence of the derivatives in the calibration of chromium-tanning solutions was also studied.