Effect of phosphorus in the molten iron on the performance of electrochemical sulfur sensor prepared by ZrO2(MgO)/CaAl2O4+CaAl4O7

Abstract The effect of the phosphorus in the molten iron on the performance of sulfur sensor was investigated, where the sulfur sensor was prepared by bilayer system of ZrO2(MgO)/CaAl2O4+CaAl4O7. The behavior and mechanism were also studied in this work. The results indicated that the CaS auxiliary electrode for sulfur sensor could be synthesized in situ by the CaAl2O4+CaAl4O7 coating at the measurement condition of a [ S ] a [ O ] ≥ 40 .85 and a [ P ] ⋅ a [ O ] 5 2 ≤ 4 .34 × 1 0 − 7 in the molten iron. The effect of the phosphorus on the performance of the sulfur sensor was attributed to the effect on sulfur activity coefficient. In contrast, when a [ S ] a [ O ] ≥ 40 .85 and a [ P ] ⋅ a [ O ] 5 2 ≥ 4 .34 × 1 0 − 7 was satisfied in the molten iron, the assembled sensor would not response to sulfur signal, but to phosphorus signal. The assembled sensor would be in effect to be the phosphorus sensor. This work would be beneficial to the practical application of the fabricated sensor in the iron and steel metallurgical industry.