Solid Phase Extraction for the Determination of Methylene Blue Using Lignocellulosic Biosorbent in Aqueous Solutions

The recent introduction of a large number of synthetic dyes, which are toxic, mutagenic, and carcinogenic, has made the situation worse by disrupting normal aquatic life. For this reason, the detection and removal of dyestuffs in wastewater become important. In this study, for the extraction of methylene blue, used as solid phase extraction adsorbent, lignocellulosic biosorbent of tea waste activated with ZnCl₂ was prepared. The factors affecting its extraction were studied in detail. To determine the sensitivity and certainty of the solid phase extraction process; optimized to have an adsorbent amount (75 mg), wash solvent (3 mL water), loading volume (20 mL), elution solvent methanol/acetic acid (80:20, v/v), and eluent volume (8 mL). As a result of the optimization processes, rates ranging from 94.4% to 98.9% recovery were obtained in methylene blue extraction in aqueous solutions. According to the results obtained, this method can be extensively applied in the efficient removal of colored contaminants.