Dual Function of Modified Palm Leaf Sheath Fibers in Adsorbing Reactive Yellow 3 and Cr(VI) From Dyeing Wastewater

Abstract

The safe and effective treatment for dyeing wastewater including harmful metal ions, which are important environmental pollution sources, has not been solved in the realistic industry. Using natural materials with short regeneration cycle should be valued in recognized and effective adsorption techniques. In this study, hydroxyl-rich tannin molecules were successfully modified on palm leaf sheath fibers (PLSF) to obtain multifunctional adsorbent for simultaneous removal of dye molecules and heavy metal ions in dyeing wastewater. As a result, modified PLSF can effectively adsorb reactive yellow 3 (RY3) dye molecules with a maximum adsorption capacity of 83.19 mg/g from dyeing wastewater, while the sample loaded with RY3 can adsorb Cr(VI) with a maximum adsorption capacity of 189.48 mg/g. XRD, SEM, FT-IR, and stereomicroscope are used to characterize the adsorbent samples. The kinetic and thermodynamic analysis results show that the adsorption of RY3 and Cr(VI) by the adsorbent is consistent with pseudo-second-order kinetics and the Langmuir isotherm model. The thermodynamic parameters of Cr(VI) adsorption indicate that adsorption is a spontaneous endothermic process and has good reusability of Cr(VI).