Microwave-Assisted Extraction of Polyphenols from Eucalyptus Bark—A First Step for a Green Production of Tannin-Based Coagulants

Tannins are natural polyphenolic compounds widely found in plants. The production of coagulants for water treatment is one their new applications. Polyphenols extraction the first step synthesizing tannin-based coagulants. Eucalyptus globulus bark (EGB), an abundant by-product pulp and paper industry, usually applied as fuel energy production, was used this work a tannin source. polyphenols from EGB studied using solvent. Extraction assays employing different techniques were conducted. Microwave-assisted showed superior performance further optimized. influence irradiation time, water-to-bark ratio, temperature evaluated Response Surface Methodology. yield total phenolic content extract modeled function conditions. overall best conditions that maximize both responses obtained through multi-response optimization. Optimized values (15% 354 mg gallic acid equivalents per gram extract) predicted time 15 s, liquid-to-solid ratio 48.5 mL/g, 141 °C. generated under these presented condensed 645 mg/g, expressed terms catechin equivalents. good tannin-extractable contents to produce