Simultaneous determination of chromium and basicity in tanning liquors using spectrophotometry and multivariate calibration

In this paper a method for the simultaneous determination of the percentage of Cr2O3 and basicity (Schorlemmer degrees, degrees Sch) in commercial sam ples is presented. This method is based on the dilution of the sample, foll owed by recording the visible spectrum in the range 360-700 nm, and the app lication of a multivariate model Partial Least Squares (PLS) technique that relates the spectrum to chromium concentration and basicity. The results o btained through the application of each model have been compared. Also, the se results have been compared with the results obtained by means of classic al analysis.