Hazardous wastes are usually used in the Portland cement production in order to save energy, costs and/or stabilize toxic substances and heavy metals inside the clinker. This work focus on the stabilization/solidification on chromium (III) wastes by C(3)A and C(3)A hydrated matrix. The immobilization rate of chromium in C(3)A and the leaching characteristics of the C(3)A hydrated matrixes containing chromium were investigated by ICP-AES. The results indicated that C(3)A had a good solidifying effect on chromium using the clinkering process, however, the Cr leaching content of Cr-doped C(3)A was higher than that of hydrated C(3)A matrix in Cr(NO3)(3) solution and was lower than that of the hydrated C(3)A matrix in K2CrO4 solution, no matter the leachant was sulphuric acid & nitric acid or water. To explain this, C(3)A formation, chemical valence states of chromium in C(3)A, hydration products and Cr distribution in the C(3)A-gypsum hydrated matrixes were studied by XRD, XPS and FESEM-EDS. The investigation showed that part of Cr3+ was oxidized to Cr6+ in the clinkering process and identified as the chromium compounds Ca4Al6O12CrO4 (3CaO center dot Al2O3 center dot CaCrO4), which resulted in the higher leaching of hydrated matrix of Cr-doped C(3)A. (C) 2014 Elsevier B.V. All rights reserved.