An Eco-Friendly Alternative Biosorption of Heavy Metal Removal from Industrial Wastewater: Characterization and Application

Rosmarinus officinalis biowaste (ROB) is obtained as a by-product from local extraction industries of essential oils. It contains a high percentage of lignin and cellulose. Therefore, in this study, the use of ROB in the removal of heavy metal ions from electroplating wastewater was investigated. The biosorption experiments were carried out batch-wise where the influence of physicochemical key parameters such as initial pH solution, contact time, initial adsorbate concentration, amount of biosorbent, and biosorbent particle size were evaluated. The results of the study indicated that with the increased adsorbent doses the adsorption capacity values decreased while the removal percentage of adsorbate increased, whereas, no influence of particles’ size was evidenced. Heavy metal biosorption is highly pH-dependent, and the maximum biosorption occurred at pH 5. An application study using industrial waste for heavy metal removal was also carried out at pH 7. It was concluded that ROB can be used as a cost-effective and efficient adsorbent for the removal of heavy metals and cationic dyes from contaminated waters.