Green synthesis of biomass-derived activated carbon/Fe-Zn bimetallic nanoparticles from lemon (Citrus limon (L.) Burm. f.) wastes for heterogeneous Fenton-like decolorization of Reactive Red 2

Abstract

Green synthesis of catalyst and catalyst supporting material with the utilization of agricultural wastes is a quite cost-effective and environmentalist approach for the removal of toxic organic compounds such as azo dyes from water sources. In this study, lemon (Citrus limon (L.) Burm. f.) by-products such as pomace and leaves, which are remained as waste after especially juice production and domestic consumption, were used for developing biomass-derived activated carbon (AC) supported heterogeneous Fenton-like catalyst. In the scope of this work, firstly; the activated carbon (Lp-AC) from lemon (Citrus limon (L.) Burm. f.) pomace was prepared, and then, it was combined with the biosynthesized Fe-Zn bimetallic nanoparticles using aqueous lemon leaves extract as a reducing agent. The final material was named as activated carbon/Fe-Zn bimetallic nanoparticles (Lp-AC/Fe-Zn NPs). The characterization of Lp-AC and Lp-AC/Fe-Zn NPs materials was carried out by using FTIR, SEM, EDX, BET and XRD methods. The biosynthesized Lp-AC/Fe-Zn NPs were utilized as a catalyst for the decolorization of a toxic azo-dyestuff, Reactive Red 2 (RR 2), with heterogeneous Fenton-like reaction and the optimum decolorization conditions were determined to be initial pH 3.0, H2O2 concentration 50 mM, initial dye concentration 100 mg L−1, catalyst concentration 0.1 g L−1, and temperature 25 °C. In the present work showed that activated carbon and Fe-Zn bimetallic nanoparticles could be synthesized through an efficient biosynthesis method using lemon waste materials which are pomace and leaves.