Efficient removal of indigo dye by using sulfonated poly (ether ether ketone) (sPEEK), montmorillonite (MMT) and sPEEK-MMT composites as novel adsorbent

In this study, indigo blue (IB) was adsorbed on individual sulfonated poly (ether ether ketone) (sPEEK), montmorillonite (MMT) and sPEEK-MMT composites for the first time. Characterizations were performed by using XRD, FTIR, SEM, HR-TEM and BET/N-2 surface area analyses, particle size and zeta potential measurements. Approximately 91% of initial amount of IB in aqueous solution was adsorbed by all adsorbents at the end of equilibrium time. The highest maximum adsorption capacity reported in literature was achieved by using sPEEK-MMT (1:10) with Qmax as 833.30 mg IB/g adsorbent. Therefore, it can be presented as an innovative adsorbent to limit IB emissions.