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In situ high-temperature X-ray diffraction studies of reduction of K2CrO4 and the formation of K x CrO y compounds

  • Shu-ting Liang (a1) (a2), Hong-ling Zhang (a1) (a2), Min-ting Luo (a1) (a2), Yu-lan Bai (a3), Hong-bin Xu (a1) (a2) and Yi Zhang (a1) (a2)...


In this work, the reduction mechanism of potassium chromate (K2CrO4) was investigated via in situ high-temperature X-ray diffraction coupled with Fourier transform infrared spectroscopy. During the hydrogen reduction of K2CrO4, the formation of K3CrO4, KCrO2, and K x CrO2 were detected for the first time. The study discovered that K2CrO4 was firstly reduced to K3CrO4 and an amorphous Cr(III) intermediate product at low temperature (400–500 °C). Moreover, the K3CrO4 was the only crystalline material at this stage. As the temperature increased, a stabilized amorphous CrOOH was formed. At a high temperature (550–700 °C), KCrO2 was generated. Interestingly, a portion of KCrO2 was spontaneously decomposed during the hydrogen reduction, accompanying by the formation of K0.7CrO2. Finally, the results clearly illustrated the reduction mechanism of K2CrO4: K2CrO4 → K3CrO4 → amorphous intermediate → KCrO2.


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In situ high-temperature X-ray diffraction studies of reduction of K2CrO4 and the formation of K x CrO y compounds

  • Shu-ting Liang (a1) (a2), Hong-ling Zhang (a1) (a2), Min-ting Luo (a1) (a2), Yu-lan Bai (a3), Hong-bin Xu (a1) (a2) and Yi Zhang (a1) (a2)...


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