| 摘要 |
<p>PROBLEM TO BE SOLVED: To suppress the leaching of hexavalent chromium contained in cement in a hardening process by adding barium chloride to the cement. SOLUTION: Barium chloride is added to cement, e.g. Portland cement such as ordinary Portland cement, high early strength Portland cement or moderate heat Portland cement or mixed cement such as fly ash cement, blast furnace cement or silica cement obtd. by mixing Portland cement with fly ash, granulated blast furnace slag or silica. The barium chloride is, e.g. dihydrate, monohydrate or anhydrous salt but anhydrous salt is preferably used from the viewpoint of handling. The amt. of the barium chloride added is preferably 1.5-2.5 pts.wt. (expressed in terms of anhydrous salt) based on 100 pts.wt. Portland cement. The leaching of hexavalent chromium contained in commercially available cement can be suppressed only by adding barium chloride to the cement.</p> |
