Enhancing Toluene Adsorption on ZnCl2 One-Step Modified Corn Cob Activated Carbon

Abstract

Toluene, a hydrocarbon frequently found in water due to human activities and accidents like oil spills, can pose health risks, such as nervous system irritation and liver lesions. This study aimed to develop cost-effective adsorp - tion techniques using activated carbon from corn biomass to remove toluene from water. The activated carbon, synthesized with zinc chloride surface modification and carbonization, was tested in a continuous fluidized bed column. The adsorbents effectively removed toluene, with optimal conditions identified as a bed height of 10 cm, a temperature of 30 °C, and a flow rate of contaminated water at 15 L/h. Operational parameters, like flow rates (15–25 l/h), bed heights (6–10 cm), and temperature (30–40 °C), were varied to assess their impact on toluene adsorption efficiency. Increasing flow rate and temperature reduced toluene removal, while higher bed height im - proved removal efficiency. However, column adsorption showed lower efficacy due to limited access of adsorbates to surface sites caused by low retention times within the column. On the basis of the breakthrough curve of 0.2 mm AC particles, the maximum adsorption capacity for toluene was 0.15643 mg/g with a total removal efficiency of 44.894%. The analysis, using various kinetic models like Thomas and Adams-Bohart, correlated strongly with the Thomas model (R 2 > 0.89), indicating Langmuir isotherm behavior and a second-order kinetic reaction. These findings demonstrate the potential of using the activated carbon from corn biomass in adsorption processes for removing toluene from contaminated water .