Thermodynamic models for predicting phosphorus distribution ratio P and phosphate capacity C PO 32 4 of CaO-FeO-Fe 2 O 3 -Al 2 O 3 -P 2 O 5 slags during secondary refining process of molten steel, according to the ion and molecule coexistence theory (IMCT), i.e. IMCT2 P and IMCT2C PO 32 4 4 against the aforementioned parameters can be observed for the slags in the higher temperature range from 1918 to 1927 K. The influences of the aforementioned parameters on dephosphorisation ability are significantly different from those on dephosphorisation potential of the slags.

Abstract-The

A thermodynamic model for predicting sulphur distribution ratio L S between CaO-FeO-Fe 2 O 3 -Al O -P O slags and liquid iron, i.e. the ion and molecule coexistence theory (IMCT)-2 3 2 5 L S model, has been developed for slags in a large variation range of slag oxidisation ability based on the IMCT. The developed IMCT-L S model has been verified with measured data of oxygen, pho-The results indicate that the desulphurisation reaction is mainly controlled by reactionthe reducing zone with the optimised standard molar Gibbs free energy change of D r G H m;CaS ¼ 147 023:63 2 27:94T ðJ mol 21 Þ; the desulphurisation reaction is dominated by reactionthe oxidising zone with the reported standard molar Gibbs free energy change of D r G H m;FeS ¼ 115 526 2 33:35T ðJ mol 21 Þ. The influence of CaO on the desulphurisation ability of the slags can be counteracted by that of Fe O because higher CaO content corresponds to lower Fe O content in the slags. An asymmetric V type relationship between sulphur distribution ratio L S and the mass action concentration ratio N FeO =N CaO or N Fe 2 O 3 =N CaO or N FeO•Fe 2 O 3 =N CaO or N Fe t O =N CaO , or the mass percentage ratio (%FeO)/(%CaO) or (%Fe 2 O 3 )/(%CaO) or (%Fe O)/(%CaO) or the simplified complex basicity ð%CaOÞ=½ð%Al 2 O 3 Þ þ ð%P 2 O 5 Þ or optical basicity can be established for the slags equilibrated with liquid iron in a temperature range from 1811 to 1927 K (1538 to 16548C). The abovementioned mass action concentration ratios or mass percentage ratios of various iron oxides to basic oxide CaO can be recommended to represent the comprehensive effect of iron oxides Fe O and basic oxide CaO on desulphurisation ability of the slags.

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Solid oxide fuel cells (SOFCs) are efficient and fuel flexible electrochemical energy conversion devices that can power the future green society with regards to homes, cars, and even down to portable electronics. They do have the potential to become low cost, since no noble metals are used. Their broad commercialization, however, is hampered by the high operating temperatures of 700–900 °C. Lowering the operating temperature of SOFCs is challenging as both the charge transport in the solid electrolyte and oxygen exchange reactions are thermally activated processes. Herein, the recent progress in the development of anode, electrolyte, and cathode materials to lower the operating temperature of SOFC below 600 °C is summarized and the new opportunities, as well as challenges that remain to be solved, are discussed. The focus of this review is addressed to thin film SOFCs, sub‐micrometer SOFCs (μSOFCs) based on microelectromechanical systems, as well as devices based on proton‐conducting oxide electrolyte (protonic ceramic fuel cells), which are especially promising for powering portable devices.