Method for treating waste water

摘要

A method for treating phosphate-containing waste water comprising treating phosphate-containing waste water with a metal hydroxide complex as a phosphate adsorbent represented by formula (1) : M1-x<2+>Mx<3+))2+x-y(A)y/n wherein M<2+> represents at least one divalent metal ion selected from the group consisting of Mg<2+>, Ni<2+>, Zn<2+>, Fe<2+>, Ca<2+> and Cu<2+>, M<3+> represents at least one trivalent metal ion selected from the group consisting of Al<3+> and Fe<3+>, A represents n-valent anion, 0.1≤x≤0.5, 0.1≤y≤0.5 and n is 1 or 2 to adsorb phosphate is provided.