Optimizing Date Seed Coagulant Extraction Process for Effective Wastewater Treatment: A Response Surface Methodology Approach With Ultrasound Assistance

ABSTRACT This study applies response surface methodology to optimize the experimental conditions for ultrasound‐assisted extraction of the active component from Saudi Khenaizi date seeds. The effectiveness of the extraction was evaluated through the coagulation process using synthetic wastewater, focusing on colour and turbidity removal efficiencies. A three‐factor (temperature, sonication time, and solvent concentration) with three levels Box–Behnken design was employed. The results revealed that sonication temperature and solvent concentration were the primary factors influencing the recovery of the active ingredient. Additionally, these factors significantly influenced the removal efficiencies ( p ‐value < 0.05). While the interaction between factors was not significant when NaCl solvent was used, the interactions between temperature and sonication time, as well as sonication time and solvent concentration, were significant when NaOH solvent was employed. The quadratic models demonstrated reasonable prediction capability for the experimental values, with R 2 values of 87.33% and 98.65% for colour and turbidity responses using NaCl solvent and 98.37% and 95.89% when NaOH was employed. Furthermore, the optimum conditions for the extraction process using each solvent were determined and experimentally validated. NaCl was found to be more favourable for turbidity removal (89.39% removal efficiency), while NaOH was more favourable for colour removal (70.95% removal efficiency). The findings of this study highlight the importance of optimizing natural coagulant extraction processes. By developing sustainable methods for wastewater treatment, this research offers valuable solutions that can be applied globally, contributing to environmental conservation and resource efficiency.