STUDY OF SALT OXIDATOR TYPE INFLUENCE ON PHYSICHOCHEMISTRY OF PATCHOULI BIOCHAR – CR2O3 COMPOSITE AND ORGANIC CONTAMINANT ADSORPTION

Organic wastewater, including drug wastewater, creates serious problems in life due to its risks, such as drug retention and toxicity for both human or animals. Biochar is a porous material which can be used as adsorbent for wastewater remediation. Formation of composite by impregnating the biochar with metal oxides can improve performance of biochar in adsorption. Oxidation of biochar surface before the impregnation was studied in this research. Purpose of this research is to study itseffect on its characteristics and adsorption of paracetamol, as the contaminant model. Synthesis was conducted in some steps, including preparation of the activated biochar from patchouli biomass through pyrolysis at 450oC using ZnCl2 activator, functionalization of biochar using 3 different salts (KMnO4, K2S2O8, K2Cr2O7) at 60 oC, impregnation of the activated biochar using CrCl3 0.9 M, and calcination of the biochar-CrCl3 composite to form biochar-Cr2O3 composite at 600 oC. Adsorption test used paracetamol (100 ppm) as pollutan model with batch method (175 rpm, 24 h). X-ray diffraction characterization indicated impregnant structure of Cr2O3. Characterization using FTIR spectrophotometry showed different patterns, especially connected to C=O and OH bands by using oxidators in sequence of K2S2O8 > KMnO4 > K2Cr2O7. SEM-EDX characterization showed different content of Cr (III) in the composites prepared in oxidator sequence of K2Cr2O7 > K2S2O8 > KMnO4. SEM images of the composites indicated the irregular ball shapes. Adsorption values were obtained more in same sequence of oxidator type based on FTIR spectrophotometry characterization than SEM-EDX.