Removal of carbendazim from aqueous solutions by adsorption on different types of zeolite

Abstract

Objective: Due to the avid interest in devising economically and environmentally viable and readily available materials for pesticide-contaminated water treatment, the effectiveness of clinoptilolite, a natural zeolite, its modified Na-form, as well as ZSM-5, a synthetic zeolite, was investigated for the removal of the fungicide carbendazim from aqueous solutions.

Methods: The removal was investigated using batch adsorption by mixing zeolite and the carbendazim solution at different contact times. At the end of each experiment, the suspensions were filtered, and the residual concentration of carbendazim in the filtrates was measured using high-performance liquid chromatography (HPLC). The experimental results were used to calculate the efficiency of tested zeolite types for the removal of carbendazim from aqueous solutions.

Results: Synthetic zeolite was highly effective (94.5%) in removal of carbendazim from aqueous solutions when compared to natural zeolite (19.5–23.3%) and its Na-form (22.5–29.0%). However, the residual carbendazim concentration for all three zeolites tested was above the maximum allowable concentration (MAC).

Conclusion: Zeolite ZSM-5 exhibited outstanding properties for the removal of the carbendazim fungicide from aqueous solutions; however, high production costs could be a limiting factor for a wider application in water treatment. For practical applications, natural zeolite may be a more economically viable choice, regardless of its significantly lower removal efficiency. Its surface properties would need to be modified and improved by organic surfactants, which would require additional experiments. Finally, the cost-effectiveness of modified natural zeolite should be compared to the production cost of synthetic zeolite to determine the most effective, economically advantageous, and environmentally friendly solution for the treatment of pesticide-contaminated water.