Ideal pH for the adsorption of metal ions Cr⁶⁺, Ni²⁺, Pb²⁺ in aqueous solution with different adsorbent materials

Abstract Industrialization increases the number of heavy metals released into environment. Lead (Pb 2+ ), nickel (Ni ) and chromium (Cr 6+ are among these toxic cause irreversible effects on ecosystems human health due to their bio-accumulative potential. The decontamination through adsorption processes using lignocellulosic wastes from agricultural and/or forestry is a viable solution. Hence, this work aimed at studying effect pH biosorption metal ions four different by-product materials: walnut shell, chestnut pinewood burnt pinewood. These experiments were conducted with solutions three in which adsorbents immersed measure rate adsorption. A range values 3.0 7.5 was used experiments, concentrations determined by atomic absorption. results showed behaviour biosorbent materials when applied metals. lead had an ideal 5.5–7.5 shell as adsorbent, corresponding greater than 90%, but for other materials, maximum occurred 7.5. For chromium, very heterogeneous all adsorbents, optimal varying (for shell) 6.5 wood). nickel, best around 5, according material used. indicate that tested biosorbents have potential decontaminate wastewater variable extensions controlling solution; more efficient removal can be achieved.