Usability of spent Salvia officinalis as a low-cost adsorbent in the removal of toxic dyes: waste assessment and circular economy

The removal of methylene blue (MB) and maxilon yellow (MY) dyes from aqueous solutions was investigated by an adsorption process using spent Salvia officinalis (SSO) for the first time. operating conditions mechanisms MB-SSO MY-SSO systems were determined. FTIR-ATR SEM-EDAX analyses also performed to characterise adsorbent. Optimum in each system similarly obtained, excluding pH (5.7 MB 6.5 MY). dye efficiency 78% 56% MY. It observed that experimental data fits Freundlich isotherm (R2 ≈ 0.97) pseudo-second-order kinetic 0.99) model both systems. maximum capacities SSO MY determined as 16.53 11.79 mg g−1, respectively. revealed affected a number active sites on adsorbent concentration dye. thermodynamic parameters confirmed spontaneous, exothermic physisorption results indicate can be used promising material solutions. However, order remove high concentrations, must activated.