Methyl Orange Adsorption onto Modified Extracted Cellulose from Olive Stones: Kinetics, Isotherms, Thermodynamic, Mechanism Studies, and Desorption

OS (olive stones) are a type of lingo-cellulosic biomass that is generated as a by-product in the olive oil industry. In this investigation, the EC (extracted cellulose) from the olive stones was modified with CTAB (cetyl trimethyl ammonium bromide) as cationic surfactant. The obtained MEC (modified extracted cellulose) was used as adsorbent to remove MO (methyl orange) from aqueous media. Various factors affecting the effectiveness of the adsorption process were examined and analyzed, such as the water’s pH values, the adsorbent dosage, the contact time, the initial MO dye concentration, and the ionic strength. The kinetic and the equilibrium studies showed that this adsorption process fit to the pseudo-second-order kinetic model and the Langmuir isotherm. The optimum adsorbed amount was about 76.92 mg/g. The thermodynamic study revealed that the adsorption was spontaneous and exothermic with an increase in the randomness. The result of the desorption indicated that the MEC was efficiently recycled with 86.78% uptake for MO after three cycles of desorption-adsorption. Finally, this investigation showed that the MEC is a potential bio-adsorbent for removing anionic dyes from aqueous media. Consequently, this bio-adsorbent can be used for future industrial exploitation to decontaminate wastewater.