Polyphenylene Sulfide Strong Based Anion Exchange Fiber: Synthesis, Characterization And Adsorption Properties

Ion exchange fiber (IEF) is a fibrous ion exchange and adsorption materials, which possesses incomparable properties such as a large effective specific surface area and short transit distance, being able to adsorb and desorb metal ions, poisonous and deleterious compounds at a high rate, compared with the traditional ion exchanger.Strong base ion exhange fiber has broad application in ultrapure water preparation, air purification, the separation of heavy matel and biomacromolecule, catalyst carrier, et al. However, the preparation method of strong base ion exchange is limited, complex and costly.A novel fibrous strong base anion exchanger (QAPPS) was firstly prepared via chloromethylation and intercrosslinking of polyphenylene sulfide (PPS) fiber and succedent quaternary amination reaction, and its physic-chemical structure and properties were primarily characterized by FT-IR, X-ray energy spectrum, TG-DTG, elementary analysis and chemical titration, respectively. The novel functional fibers possessed high exchange capacity (3.51 mmol/g), and presented a very goog chemical stability in srtong acid and alkaline solution, its antioxidant capacity was better than commercial strong base anion exchange resin. According to the TG and DTG curves, the functional groups of the fibers nearly had no degradation before 200℃. Compared with the existing PP-ST-DVB-based strong base anion exchange fiber, the novel preparation process of strong base anion exchange fibers was simple, lower cost and facile commercialed.The adsorption behavior for Cr (Ⅵ) of the fiber was studied using a batch technique. The influence of pH, initial concentration, temperature and contact time was investigated. The fibers could effectively adsorb Cr (Ⅵ) at the pH 1-12 and the maximum adsorption occurs at pH=3.5. The adsorption data was consistent with Langmuir isotherm equation model and the maximum adsorption capacity of QAPPS was 166.39 mg/g, which is more than that of commercial fiber Fiban A-1 (144.21 mg/g). The thermodynamic parameters for the adsorption have been evaluated. The rate constants were studied using the pseudo-first-order and pseudo-second-order models. The t1/2 was less than 5 min and equilibrium could be obtained in 20 min. The anion exchange fibers adsorbed Cr(VI) could be regenerated rapidly by the mixed solution of 0.5 mol/L NaOH and 0.5 mol/L NaCl, the removal rate remained 98%and the adsorption capacity remained 96% after six cycles.