The investigation of some properties of cement and removal of water soluble toxic chromium(VI) ion in cement by means of different reducing agents

In this study, solid lignin produced from lignin liquor which is a waste of paper industry, and Sb2O3, MnSO4 center dot H2O, K-2(SbO)(2)C8H4O10 center dot 3H(2)O and FeSO4 center dot H2O were investigated in terms of their reducing effect on Cr(VI) and other effects on cement properties. Test results revealed that Sb2O3 and MnSO4 center dot H2O are able to reduce Cr(VI) effectively when they were used at levels of 0,02% and 0,25% by weight of cement respectively and these amounts in cement did not cause any negative effect on concrete properties of cement. Also, they performed stable reducing effects when exposed to high temperature tests and shelf life tests and it is concluded that they can be used conveniently to reduce Cr(VI) in cement industry. (C) 2016 Elsevier Ltd. All rights reserved.