Acrylic-modified PET fiber cloth and its adsorption properties for copper ions

With the advancement of science and technology, the problem of wastewater pollution is escalating and there is an urgent need to focus on wastewater treatment. After the bromination reaction of Polyethylene terephthalate (PET) as an adsorption substrate (It is used to remove heavy metal ions), PET-g-PAA adsorption material was synthesized through the grafting polymerization of PET with poly(acrylic acid) (PAA) derived from the free radical polymerization of acrylic monomer. The intricate structure of the composite material was meticulously analyzed using a range of sophisticated techniques. The optimum polymerization and adsorption conditions of PET- g -PAA for Cu(II) under different conditions were investigated. The optimum polymerization conditions were 1.0 g polymer mass, 2 h polymerization time, 50 °C reaction temperature and 1 cm × 1 cm PET fiber cloth. Under conditions where the Cu(II) solution concentration was 20.48 mg/L and the adsorption process occurred at 50 °C, the peak adsorption efficiency of PET-g-PAA reached 83.70 %, accompanied by an optimal adsorption capacity of 16.85 mg/g. The adsorption curves of PET- g -PAA on Cu(II) fitted well with the pseudo-second-order kinetic model and Freundlich isotherm model, indicating that the adsorption process belongs to chemisorption. Moreover, the initial adsorption rate (h = 20.16 mg/g·min) is larger, indicating that the adsorption rate of PET-g-PAA is faster. The adsorbent belongs to multilayer adsorption on a multiphase surface. The heterogeneity factor was greater than 2 and less than 10, which proved that the adsorption process of adsorbent was favorable. On the basis of adsorption thermodynamics, Δ G 0  < 0 kJ/mol, Δ S 0  = 39.82 kJ·mol −1 ·K −1 , ΔH 0  = 8.36kJ/mol, indicating that the adsorption of Cu(II) by PET- g -PAA was a spontaneous endothermic and favorable process. The PET-g-PAA adsorbent achieving exceptional heavy-metal removal efficiency, enhanced reusability, and cost-effectiveness for sustainable wastewater remediation—a significant advancement over conventional single-use or non-scalable adsorbents.