Box-Behnken approach for optimization of Cr(III) removal from a real tanning effluent using powdered marble

During the tanning step, 30–40% of trivalent chromium remains in solid and liquid wastes, generating highly polluted sewage. In this study, powdered marble was used as a low-cost adsorbent to remove from synthetic solution real effluent. Batch adsorption experiments on were performed. After incubation, samples filtered uptake determined. A 3-level Box-Behnken Design study combined effect initial concentration, pH values dose removal chromium. The results showed that maximum (> 99%) obtained at concentration 0.758 g/L, = 5.0 using 6% (w:v) marble. Adsorption isotherm satisfactorily described by Langmuir model. toxicity effluent examined before after adsorption. Phytotoxicity (Lepidium sativum) assays revealed an improvement germination index rising 0 35% adsorption, respectively. Microtoxicity (Escherichia coli) decrease growth inhibition percentage going 100 31% following experiment raw Desorption indicated nearly 45% adsorbed recovered 4% (v:v) HCl. Overall, is effective economical alternative with great potential for recovery.