The research conducted here will hopefully lead to the creation of a practical, inexpensive method for purging aqueous solutions of contaminating phenolic chemicals. A biosorbent system comprised of eggshells and iron was studied for its potential to effectively detoxify phenol. Both the eggshell and the iron systems were used in the preparation of the adsorbents in order to achieve the desired result of having the properties of both systems. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) were used for characterisation. Batch tests were conducted to evaluate the adsorption capacity of eggshells and iron under the influence of different operating parameters (shaking speed, pH, initial phenol content, and contact time). In the design-expert modelling, the optimisation conditions were found to be a pollutant concentration = 30.0 mg . L–
1, pH of 3.00, adsorbent dose = 0.11 mg . L–
1, shaking speed = 150 rpm, and time = 120 min for an phenol reduction rate of 94.4 % which it was extremely near to the experimentally value (96.6 %). The CCD modelling that was performed in the RSM verified the findings that were predicted. On the basis of laboratory results, the prediction proved accurate.