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Activity of the catalyst obtained by processing of high-magnesia siderites
Published in Vladimir Litvinenko, Topical Issues of Rational Use of Natural Resources 2019, 2019
A.N. Smirnov, S.A. Krylova, V.I. Sysoev, V.M. Nikiforova, Zh.S. Zhusupova
The basis of siderite ores is iron carbonate - FeCO3, which scarcely can be found naturally in pure form and often has an isomorphic admixture of magnesium, as well as manganese, calcium and other elements (Dziubinska et al. 2004). Iron carbonate forms a continuous isomorphic series with magnesium carbonate - from pure FeCO3 (siderite) to pure MgCO3 (magnesite). In the isomorphic series, stable members of the series are distinguished depending on the MgCO3 content: sideroplesite - up to 30%; pistomesite - from 30 to 50%; mesitite - from 50 to 70% and breynerite - from 70% and higher.
EUROCORR 2019: ‘New Times, New Materials, New Corrosion Challenges’ – Part 1
Published in Corrosion Engineering, Science and Technology, 2020
‘Understanding the role of aqueous NaCl solutions on corrosivity of carbon steel and FeCO3 formation’ was described by M. M. Alsalem (Imperial College, London, UK). In CO2 corrosion, the formation of iron carbonate (FeCO3) scale is instrumental in governing the rate of general corrosion. The introduction of NaCl to CO2-saturated aqueous solutions reduces CO2 solubility, thus causing a decrease in the concentration of the dominant corrosive species − carbonic acid (H2CO3). It was found that exposure of carbon steel to 3% w/v NaCl at 80 °C (∼pH 6) in CO2-saturated solution led to an increase in corrosion resistance. Starting at 24 h, the resistance was further enhanced as siderite crystals dominated the surface to form a barrier that blocked active sites and reduced the diffusivity of corrosive species towards the metal surface.