Removal of Methylene Blue Dye from an Aqueous Solution by an Adsorption Technique Using Sulfonated Polystyrene as Three Low-cost Adsorbents

In this study, three alternative techniques were used to recycle expanded polystyrene waste (WPS). Sulfonated polystyrene (PSS)-based materials (PSS-01, PSS-02, and PSS-03) were produced and employed as efficient and reasonably priced adsorbents. The findings demonstrated that the clearance efficiency of expanded polystyrene increased from 13.6% for pH = 3 to 21% at pH = 9. The removal capacity for sulfonated polystyrenes, which varied from 60% to 85% and 98% for PSS-01, PSS-02, and PSS-03, respectively, did not alter over the pH range. Furthermore, the removal effectiveness of the sulfonated polystyrenes was unaffected by increasing the starting dye concentration. However, for a methylene blue (MB) concentration of 200 mg l-1, the removal capacity employing PSS-02 significantly decreased and fell to less than 62%. The elimination rate of the dye by PSS-03 at the ideal contact duration of 15 min was more incredible than 98.2% at the ideal amount of 20 mg. Undoubtedly, the results showed that MB adsorption corresponded to the Langmuir isotherm for WPS and PSS-02 and the Freundlich isotherm for PSS-01 and PSS-03, and adsorption kinetic models for the three copolymers produced pseudo-second order. PSS-03's adsorption capability increased because of its hydrophilic sites and higher adsorbent surface area.