Determination of Chromium Oxide in Chrome Ores by Automatic Potentiometric Titrimetry with Microwave Digestion Sample Preparation

A method for the determination of Cr₂O₃ in chrome ores by automatic potentiometric titrimetry technology coupled with microwave digestion under high-pressure was developed. The method has been tested by determination of Cr₂O₃ in 2 National Standard Reference chrome ore samples with wide range of Cr₂O₃ contents.The results were in agreement with certified values with relative error of 0.015％~0.021％ and the precision of 0.089％~0.102％ RSD (n=20). Six imported inspection samples were also tested by the method and the results were in accordance with those from classical method. The method provides the advantages of low energy consumption, low labor intensity, high efficiency and is suitable for the daily inspection work.