Surface Active Effect of Na2O on the Rate of CO2 Dissociation on the Surface of Molten FeOx-Na2O and FeOx-SiO2-Na2O Systems

Oxygen Exchange Reaction between CO2-CO Gas and Molten Oxide Containing Iron Oxide

“…In this figure, the CO 2 dissociation rate constants measured by isotope exchange technique with CO 2 -CO gas containing isotopic carbon ( 13 C or 14 C) were also represented for comparison. 3,4,6,8,9) The rate constants measured in the present study were approximately one order of magnitude larger than that measured in the previous studies. The previous results measured by many researchers including authors are mutually accordant and also correspond to those calculated from the oxidation or reduction rates of molten oxide.…”

“…On the contrary, the effect of SiO 2 addition on the ferric-ferrous ratio was not clearly observed. Authors 8,9) previously measured that ratio for the FeO x and FeO x -SiO 2 systems containing 26 and 30 mass% SiO 2 and the ferric-ferrous ratio slightly decreased with adding SiO 2 . The observed ferric-ferrous ratios in the present study were somewhat larger than those in the previous study.…”

“…(9) from the mass balance for 18 O in the reaction system, 2) .................... (9) where n18 O is the number of mole of 18 O transferred to melt. t is time, V and T are volume and temperature of gas, and R is gas constant.…”

“…Especially, the 14 CO 2 -CO and 13 CO 2 -CO isotope exchange technique has been utilized to measure the interfacial chemical reaction rate of CO 2 and CO gas on the surface of various molten oxide systems and many valuable results have been obtained. [1][2][3][4][5][6][7][8][9][10] In the field of catalyst, O 2 , CO 2 , H 2 O and CO enriched 18 O have been used to investigate the mechanisms of oxygen exchange reaction on the surface of solid metal and oxide as catalysts at lower temperature. [11][12][13][14][15][16] Some researchers 12) have noticed that the effect of oxygen diffusion in bulk of solid metal and oxide on the overall process became bigger with the increase of temperature and must be considered.…”

Interfacial Rate of CO2^|^ndash;CO Reaction with the Solid Iron and Iron Oxide by Isotope Exchange Technique at 1273 K

“…From the 1960s, the isotope exchange technique, as an effective experimental method to study the interfacial kinetics between gas and iron oxide, has been extensively used by many researchers in metallurgical field. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] Recently, in order to meet the strong demand on the utilization of low grade iron ores and reduction of CO2 emission, the direct reduction of fine iron ore, as an innovative ironmaking process, has been given more attention. Therefore, the kinetics of CO2-CO reaction with the solid iron oxide became more important.…”