Study of the thermal behavior of organic binders used in oxide-carbon refractory bricks

C.L.PÁSSERA; L.B. MANFREDI; A.G. TOMBA MARTINEZ

METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE

SPRINGER

Año: 2021 vol. 52 p. 1681 - 1694

1073-5615

Organic substances are used in refractory bricks manufacture as binders. In this work, two commercial binder systems currently employed in MgO-C bricks for steelmaking industry, were first analyzed separately from the other components of the refractory. A resol phenolic resin alone and mixed with an ecobinder produced by treatment of tar pitch were studied by several techniques (XRD, FTIR, Raman spectroscopy, DTA/TGA and measurements of density, porosity, and mechanical and oxidation resistances) in their as-received condition, as well as after thermal treatments in conditions near to those used in the manufacture of the bricks (temperatures lower then 300°C) and also during their service (in the range 600 to 1400°C). The comparative analysis of the obtained results indicates that the ecobinder has domains of ordered carbon in its original condition, although the resin forms a stronger three-dimensional structure after treatments at low temperature (< 300°C). When both binders are mixed and temperature rises from 600°C onwards, experimental data show that they evolve with no or little interaction; the produced carbon has more and larger crystalline regions when the ecobinder is present. Finally, the effect of the binders? characteristics on some properties of MgO-C bricks which have them incorporated were briefly analyzed.