abstract |
The present invention provides methods for resisting corrosion of metal elements in concrete, and associated compounds and structures. Acid mine drainage sludge is used as a source of a precursor compound that reacts with a source of anion to form a chloride-sequestering compound. The precursor compound may have the formulan n2Me′(II)O·(Y (2−x) ,Y′ x )O 3 +qMe′(II)O,n n where at least one of Y and Y′ is present; Y and Y′ are different and are independently selected from the group consisting of Al, Fe, Cr, and not present; Me′ is a cation and is selected from the group consisting of Ca, Ba, Sr, Mn, and Zn; x is a number ranging from 0 to 2; and q is a number ranging from 0 to 2; and combinations thereof. In a preferred embodiment, the precursor compound has the formula 2CaO(Fe (2−x) ,Al x )O 3 +CaO. |