1Physical and Inorganic Chemistry Divisions, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Bandung, Indonesia, 401322
2Organic Chemistry Divisions, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Bandung, Indonesia, 40132
Abstract. This work had successfully produced Theobroma cacao L. (TCL) husk-based cellulose used efficiently and environmentally friendly simple microwave-assisted extraction (MAE) method. The microwave-assisted heating time optimization of alkaline-treatment was carried out for 10, 20, 30 and 40 minutes. Microwave-assisted bleaching process was also conducted using green bleaching agent H2O2, and also utilizing microwave heating for 60 minutes. The followed treatment was filtered, neutralized, washed and overnight freeze-dried. Fourier transform infrared (FTIR) analysis confirmed common cellulose functional groups of TLC, are β-(1,4)-glycosidic bonds at ~897 cm-1, O-H (hydrogen bond) at 3412 cm-1, C-H vibration at 2902 cm-1, C-O-C asymmetric at 1161 cm-1, and C-OH out-of-plane bending at 665 cm-1. FTIR analysis, in addition, also studied crystallinity ratio (CrR), hydrogen bond energy (EH) and hydrogen bond distances (RH), while particle size analyzer (PSA), X-ray diffraction (XRD) and thermogravimetry analysis (TGA) were carried out to confirm particles sizes, crystallinities and thermal stability properties of TCL husk, cellulose of TCL husk and commercial-microcrystalline cellulose (MCC), respectively.
Keywords: microwave-assisted extraction (MAE), Theobroma cacao L. (TCL), cellulose.