Olive Industry Solid Waste-Based Biosorbent: Synthesis and Application in Wastewater Purification

Area of Science:

• Environmental Chemistry
• Materials Science
• Waste Management

Background:

• Wastewater contamination by toxic metal ions poses a significant environmental and health risk.
• Agricultural waste, such as olive industry solid waste (OISW), represents an underutilized resource.
• Developing cost-effective and sustainable adsorbents is crucial for effective wastewater treatment.

Purpose of the Study:

• To develop a value-added adsorbent from olive industry solid waste (OISW) for toxic metal ion removal.
• To investigate the synthesis and characterization of a novel 3D polymer adsorbent.
• To evaluate the adsorption efficiency and performance of the OISW-based material for wastewater remediation.

Main Methods:

• Carboxymethylation of OISW followed by thermal curing to form ester linkages and create a crosslinked polymer.
• Characterization of the crosslinked product using FT-IR, atomic force microscopy, and thermal analysis.
• Adsorption experiments to evaluate the removal of Pb(II), Cu(II), and other metal ions from sewage, optimizing parameters like adsorbent dose, temperature, pH, and time.

Main Results:

• The synthesized crosslinked carboxymethylated OISW effectively removed approximately 20 metal ions from a real sewage sample.
• The adsorbent exhibited excellent reusability, with no significant drop in efficiency after six cycles.
• Adsorption kinetics followed the Langmuir isotherm model and second-order rate, with experimental Qe values of 13.91 mg/g for Pb(II) and 13.71 mg/g for Cu(II).

Conclusions:

• Crosslinked carboxymethylated OISW is a promising, low-cost, and sustainable adsorbent for removing toxic metal ions from wastewater.
• The material's high adsorption capacity, efficiency, and reusability make it suitable for large-scale environmental applications.
• Thermodynamic studies confirmed the spontaneous nature of metal ion bonding to the adsorbent's receptor sites.