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

• The study for the reduction of Cr(VI) and the investigation of mechanical (strength) and hydration (setting time, volume expansion) properties of cement with reducing reagents.
• The results of this study are important in terms of industrial applicability.
• These amounts in cement on article did not cause any negative effect on concrete properties of cement.

In this study, solid lignin produced from lignin liquor which is a waste of paper industry, and Sb2O3, MnSO4·H2O, K2(SbO)2C8H4O10·3H2O and FeSO4·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·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.