Simultaneous Fabrication of Ti–Si Alloy and CA–CA₂ Based Tailing Slag Cement via Aluminothermic Reduction of Ferrotitanium Slag

Abstract

Al₂O₃–TiO₂–CaO-based ferrotitanium slag is a waste slag generated during ferrotitanium-alloy smelting. At present, the TiO₂ resource (about 15 wt.%) in ferrotitanium slag has not been effectively utilized. In this study, aluminothermic reduction was used to extract Ti and prepare a Ti–Si alloy, while the low-density Al₂O₃–CaO-based molten tailing slag floating on the Ti–Si melt was separated to fabricate CA–CA₂ tailing-slag cement. The TiO₂ content decreased from 14.42 wt.% in the ferrotitanium slag to 1.63 wt.% in the tailing slag. The Ti–Si alloy was mainly composed of Ti₅Si₃ and Ti₅Si₄. The mineral composition and hydration behavior of the CA–CA₂ tailing-slag cement were similar to those of commercial calcium aluminate cement Secar71. Under the adopted preparation and testing conditions, the mechanical strength of the tailing-slag cement paste reached approximately 85% of that of Secar71, indicating its potential as an alternative refractory binder. The co-production of Ti–Si alloy and CA–CA₂ tailing-slag cement provides a potential route for the value-added utilization of ferrotitanium slag.

Keywords

Ferrotitanium slag / Ti extraction / Aluminothermic reduction / Ti–Si alloy / Tailing slag cement

Author Contributions

X.Z. analyzed the data, and wrote the original manuscript. H.G. built the model and related methodology. D.C. revised the manuscript. X.X. and L.F. analyzed the data and interpreted the results. T.L. and A.H. performed experiments and analyzed the experimental data. S.L. and Y.Z. provided the funds needed for the experiment.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data that support the findings of this study are available on request from the corresponding author.

Funding

This research was funded by [National Natural Science Foundation of China] grant number [52172023 and 52302027].

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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