Removal of Cu, Cr, Zn, and Pb from Wastewater by Using a Composite of Chitosan and Metal Organic Framework Mil (53) Fe

Wastewater exhibits elevated concentrations of heavy metals that pose significant risks to human, animal, and plant health. Using chitosan and metal-organic framework (MOF MIL (53) Fe), a composite was synthesized by hydrothermal methods to eliminate certain heavy metals (Cu, Cr, Zn, and Pb) from wastewater. The surface areas of chitosan, MOF, and their composite were evaluated using the Brunauer-Emmett-Teller (BET) method. The measured surface areas were 16.5 m²/g for chitosan, 3.5 m²/g for MOF, and 109.038 m²/g for the composite, respectively. The morphological analysis was made using a scanning electron microscope (SEM-TEM); the average size particles of chitosan, MOF, and composite were observed to be (500 to 20) µm, (50 to 10) µm, and (50 to 10) µm, respectively. The removal efficiency and the adsorption capacity for chitosan, MOF, and composite were studied at pH 7, adsorbent dose 0.3 g, initial concentration 5 ppm, and contact time 60 minutes. The mean removal efficiencies were 97.35% for chitosan, 97.45% for MOF, and 98.145% for the chitosan/MOF composite. The mean adsorption capacities were 0.81 mg/g for chitosan, 0.811 mg/g for MOF, and 0.817 mg/g for the chitosan/MOF composite. The Freundlich model more accurately describes the sorption of Cu, Cr, Zn, and Pb compared to the Langmuir model. The manufacturing process of 10 grams of chitosan costs about 70 Egyptian pounds, while 10 grams of MOF costs 700 Egyptian pounds and 10 grams of composite costs 250 Egyptian pounds.