Study of total chromium and water soluble chromium in Indian cement samples
نویسندگان
چکیده
Estimation of water soluble hexavalent chromium and total chromium has been devised. For the complete extraction of water soluble hexavalent chromium, leaching period of five days is done. It was ascertained that complete extraction was achieved in five days; the total chromium determination in these samples was done by fusing sample with sodium carbonate up to 1050 C in muffle furnace. Chromium concentration in these samples is determined with spectrophotometer using a redox indicator (1, 5 diphenylcarbazide). Samples investigated are ordinary Portland cement (OPC), Portland pozzolona cement (PPC), Portland slag cement (PSC) and clinker. The content of water soluble and total chromium in these samples ranged from 12 to 33 ppm and from 684 to 1026 ppm respectively. The accuracy of the method has been checked using a standard reference material of National Institute of Standards & Technology (NIST), USA, and found to be in permissible limits.
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