Sulfur determination in carbon-saturated iron by solid-state electrochemical sensor

Sensing of sulfur in molten metal using strontium β-alumina

“…K 5 a CaS =a Caðbeta aluminaÞ Á a S [5] Any change in the sulfur activity, therefore, will change the activity of the calcium in the beta alumina and this will be detected by the electrolyte. This will obviously apply to other beta alumina.…”

“…[4] These authors also highlighted the problem of the instability of calcium sulfide in the presence of oxygen. To overcome the problem of electronic conduction, Gozzi and Granati [5] used calcium beta0 alumina and a layer of calcium sulfide that equilibrated with the sulfur in the melt causing the activity of calcium in the calcium sulfide to alter, and this was detected by the calcium beta0 alumina electrolyte. For example, the layer of calcium sulfide on the electrolyte was assumed to dissociate into sulfur and calcium:…”

Fabrication of ZrO2(MgO)/CaAl2O4+CaAl4O7 Bilayer Structure Used for Sulfur Sensor by Laser Cladding

“…In the iron and steel metallurgical industry, on-line measurement of sulfur in liquid iron and steel has been a challenge for decades and two types of sulfur sensors have developed. One is the direct sulfur determination sensor by sulfide solid electrolyte [1][2][3][4][5], the other is the indirect sulfur sensor based on ZrO 2 with doped oxides and β-Al 2 O 3 as solid electrolyte and sulfides as auxiliary electrode [6][7][8][9][10][11]. However, all the above sulfur sensors have as a common characteristic that the solid electrolyte used for the sulfur sensor contains sulfides.…”

“…Meanwhile, this structure would also help more effectively to increase the conductivity in the sensor and avoid high electronic conductivity. The traditional methods of producing this bilayer structure is by coating the desired layer of material either by plasma spraying, flame spraying, or screen printing [6,8,9]. However, the disadvantages of these methods are that the coating may contain pinholes, and can fall off easily due to erosion of the liquid iron.…”

An electrochemical sulfur sensor based on ZrO2(MgO) as solid electrolyte and ZrS2+ MgS as auxiliary electrode

“…These have never proved to be too successful as doubts have been expressed regarding the degree of electronic conductivity in these materials. To overcome the problem of electronic conduction, Gozzi and Granati [10] searched for a sulfur sensor using Ca␤ -Al 2 O 3 with a coating of CaS auxiliary electrode. Zhang et al [11] have fabricated a sulfur sensor using ZrO 2 (MgO) electrolyte with a coating of CaO-CaS auxiliary electrode.…”