Preparation and characterization of modified PEEK-WC:DEHPA microspheres for Rhodamine B adsorption. Kinetics studies

Functionalized polymeric microspheres based on a modified polyether ether keetone (PEEK-WC) using immersion precipitation techniques were successfully prepared by doping initial polymeric solutions with DEHPA. The viscosity of the doping solution was measured for determining the optimal value for obtaining reproducible capsules. The modified microspheres were characterized by several techniques such as SEM, BET and porometer. From the results, meso-porous microspheres with a small tail were obtained characterized by an asymmetric structure and a diameter varying from 50 ?m to around 1400 ?m. The produced microspheres have been used efficiently for Rhodamine B adsorption in a column system with extraction efficiency of 99%.Moreover, the modified microspheres could be regenerated with high efficiency and a good reusability after 9 cycles of sorption and desorption. The adsorption kinetics, of Rhodamine B by the produced microspheres, was best represented by the pseudo-second-order kinetics model which confirms a chemisorption mechanism. However, the results of the intra-particle model reveal that the sorption of Rhodamine B onto the microspheres is a combination between the chemisorption and intraparticle diffusion. The findings of this study provide novel information for the development of new polymeric microspheres adsorbents towards dyes for potential applications for example in wastewater textile treatment.