Fast activation of natural biomasses by microwave heating

摘要: Abstract Microwave was effectively applied as a fast heating tool for activating two natural biomasses, pine wood and Arabica coffee residues. The heated biomasses were tested removing four food dyes: Allura Red E129, Sunset Yellow E110, Tartrazine E102, Brilliant Black E151 from solution. by 2.45 GHz microwaves at different input powers 200–1000 W 8 min. results indicated that high is necessary to activate enhance dyes adsorption. Dielectrical properties (dielectric constant ɛ ′, dielectric loss ″, tangent tan  δ , penetration depth dp ) better microwave absorber leading significant structural damage when powers. Microwave-heated showed performance removal compare residue. Heating 1000 W not recommended both where oxidation reactions destroyed the structure of materials. Moreover, long times had bad influence on removal. %Removal–adsorption capacity plot 0.8 1.0 g/100 mL optimum adsorbent dosage E110 respectively. Analysis Langmuir equation revealed saturation values 9.3 7.2 mg/g E129 pH 2.0 25 °C, receptively. Dyes microwave-heated process more than 90% adsorbent's utilised within 30 min.