Lignitic Humic Acids as Environmentally-Friendly Adsorbent for Heavy Metals

Table 4

Distribution coefficient for single Cu²⁺ ions and Cd²⁺, Cu²⁺, Pb²⁺, and Zn²⁺ ions adsorbed from their mixture.

Cu^2+ (single)	Cd^2+	Cu^2+	Pb^2+	Zn^2+
0.902 L/g	0.236 L/g	0.627 L/g	0.423 L/g	0.135 L/g