Surface carboxyl-activated polyester (PET) fibers decorated with glucose carbon microspheres and their enhanced selective adsorption for dyes

Glucose carbon microspheres have been widely used for wastewater treatment as adsorbent owing to their strong adsorption capacity, but for large-scale applications, the glucose carbon microspheres are inconvenient to be recycled from aqueous suspension due to their good suspendability. Moreover, the primitive nature of small particle size, large specific surface area and high surface energy of glucose carbon microspheres make them prone to aggregate and thus, disperse no-effectively for the other extended application. To solve this dilemma, polyester (PET) fibers decorated with glucose carbon microspheres (GC@PFs) were herein fabricated by one-step hydrothermal carbonization with acrylic acid as a coupling agent. The products were characterized by Fourier Transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Boehm titration, X-ray diffraction (XRD), Thermo-gravimetric Analysis (TG), Scanning Electron Microscope (SEM) and zeta potential respectively. The experimental results showed that a large amount of glucose carbon microspheres were evenly dispersed on the surface of carboxyl activated polyester fibers with uniform particle diameter, and the composite fibers showed desirable adsorption ability of cationic dyes for its more negative zeta potential. The dye adsorption isotherm follows Langmuir model and pseudo-second-order kinetic model better. Remarkably, the adsorbent has an excellent recyclability for maintaining a high removal rate (> 85%) to dye even after 10 cycles.