Metal nanoparticles decorated phosphorylated carbon nanotube/cyclodextrin nanosponge for trichloroethylene and Congo red dye adsorption from wastewater

In this research, insoluble nanosponge β-cyclodextrin (β-CD) polyurethane was modified with phosphorylated multiwalled carbon nanotubes (pMWCNTs) and further decorated with titanium dioxide and silver nanoparticles. This modification of β-CD polyurethane was achieved through subsequent reactions of amidation, cross polymerization, using a functional linker such as diisocyanate, and sol-gel. The new polymeric nanobiosorbent obtained was characterized by Fourier-transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM); for surface area analysis, the Brunauer-Emmett-Teller (BET) method was employed. The developed nanobiosorbent, with a high surface area (352.5m² g^-1), favors the adsorption of trichloroethylene (TCE) and Congo red (CR) dye from wastewater samples using a batch method. The solution pH, adsorbent dosage effects, isotherm, kinetic, thermodynamic as well as regeneration and desorption studies on the adsorption mechanism were also explored. The nanobiosorbent maximum capacities of removal from the Langmuir model were respectively, 27507mgg^-1 (TCE) and 146.96mg^- (CR dye). The adsorption mechanisms of TCE and CR dye were well-established and taking place via an endothermic process.