Optimization of Olea europaea Stone-Activated Carbon Preparation Using Response Surface Methodology for Thiamphenicol Removal in a Fixed Bed Column

The study addresses the persistent issue of thiamphenicol (THI) accumulation in aquatic environments and its detrimental impact on biological systems. While activated carbon is commonly used for removing such organic micropollutants in advanced wastewater treatment, this research explores the innovative use of olive stones as a feedstock for activated carbon production. The novelty of this study lies in the optimization of the activated carbon preparation process using a fractional factorial design with five critical factors: concentration, heating rate, activation temperature, activation time, and impregnation ratio. By employing the methylene blue method to determine the specific surface area (SSA), the optimal conditions were identified: a phosphoric acid solid-liquid ratio of 1:2 (74.52%), a heating temperature of 550 °C at a rate of 10 °C/min, and an activation period of 120 minutes, resulting in an SSA of 53.07 m2/g. The subsequent THI adsorption tests in a fixed-bed column revealed that THI removal efficiency was inversely proportional to flow rate and initial THI concentration, while positively correlated with bed height. This study fills a critical gap by demonstrating an effective, sustainable method for producing activated carbon from agricultural waste, optimizing the process parameters for maximum efficiency in micropollutant removal.