Design and characterisation of a functional material for the removal of phthalates from micro- and nanoplastic sources from aqueous environments by green synthesis method

Despite their indispensability in modern life, plastics pose significant threats to environment and food safety upon reaching the end of their useful life. Plastic waste, which transforms into micro- and nanoplastics over time, poses a significant threat to the environment and human health by releasing the chemicals it contains into the environment. Phthalates, a prominent chemical in this group, are utilised to enhance the flexibility of plastics; however, they have the potential to seep into the environment from waste plastics. Phthalates have been observed to accumulate in soil, water, and living organisms, resulting in endocrine-disrupting effects, particularly on the reproductive system. As evidenced by the extant literature, a variety of wastewater treatment methods have been developed with a view to mitigating the environmental hazards posed by phthalates. The predominant methods include adsorption, microbial degradation, photocatalysis, electrochemical degradation, membrane technology and advanced oxidation techniques. Each method has its own advantages and limitations. In this study, the synthesis of magnetic adsorbent (m/PA) from the Phragmites australis plant was conducted. The adsorbent was employed for the removal of diethyl phthalate (DEP) and dibutyl phthalate (DBP), which function as plasticisers, from aqueous solutions. M/PA was characterized utilizing Brunauer-Emmett-Teller (BET) analysis, scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR) spectroscopy, and zeta potential measurement techniques. In the context of the batch system, a comprehensive investigation was conducted into the parameters of pH, adsorbent amount, contact time, and phthalate concentration. After investigating the relevant parameters, the optimal adsorption conditions were ascertained to be an initial phthalate concentration of 10 mg/L, an adsorbent amount of 0.05 g/L, a contact time of 6 days, and a pH of 2. The adsorption kinetics were analysed using the pseudo-first order, pseudo-second order, and intraparticle diffusion kinetic models. The adsorption isotherms were calculated using the Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherm models.