WALNUT SHELLS AS SUSTAINABLE ADSORBENT FOR THE REMOVAL OF MEDICAL WASTE FROM WASTEWATER

Adsorption has been demonstrated to be one of the world's most effective wastewater remediation techniques. This study attempts to use walnut shells as an adsorbent for the removal of the medications Amoxicillin, Ciprofloxacin, and Tetracycline from aqueous solutions. Many variables were studied to indicate walnut shells influence on the efficiency of removal; which included pH of the solution (3-9), drugs concentration (10-60 mg/L), adsorbent concentration (0.025–0.25) g/100ml for the walnut shell, contact time (5-120 min), and agitation speed (50-300 rpm). From the experimental results, the best removal at the most suitable pH value of Amoxicillin at pH 6, for Ciprofloxacin was at pH 5 and at pH 4 for the Tetracycline. With an optimum condition, for an amount of adsorbent of about 0.25, and an optimum time of 60 min for all adsorbs using 300 rpm. The best percentage of removal was 59.32% for Amoxicillin, 62.160% for Ciprofloxacin, and 61.55% for Tetracycline when 50 mg/l concentrations of all pharmaceutical solutions. The removal is well integrated into the Freundlich isotherm model. The correlation of kinetic data by a pseudo-second-order model was successful for three antibiotics. However, this study showed that walnut shells are an effective adsorbent in removing medical contaminants from an aqueous solution of the natural environment.