Use of Modified Sorbents Based on Activated Carbon BAU-A for the Extraction of Nonferrous Metals from Aqueous Solutions

Resumo

The sorption of some nonferrous metals (Cu, Ni, Zn, Pb) from aqueous solutions by granular sorbents based on activated carbon BAU-A has been studied. The surface modification of BAU-A has been conducted by exposing it to a nitrating atmosphere (NO_x–air or HNO₃ (vapors)–air) at a temperature of 90–110°C for 4 h and impregnating it with 10 wt % of triethanolamine (TEA), tetraethylenediamine (TEDA), or carbamide (CH₄N₂O). It has been found that modification of BAU-A leads to a decrease in the sorption capacity of this material with respect to Cu²⁺, Ni²⁺, and Zn²⁺ and an increase with respect to Pb²⁺.