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Preparation and characterization of calcium oxide from crab shells (Portunus pelagicus) and its application in biodiesel synthesis of waste cooking oil, palm and coconut oil
Full text linkoai:ojs2.sciencetechindonesia.com:article/3Preparation of calcium oxide from Portunus pelagicus through thermal decomposition for 3 hours at various temperature 700°C, 800°C,900°C,1000°C, and 1100°C. The calcium oxidefrom decomposition was carried out and characterized by X-Ray Diffractometer (XRD), FT-IR spectrophotometer and SEM-EDX analyses. The result of XRD show decomposition Portunus pelagicus at 1000°C have diffraction pattern agree with the CaO diffraction standard with 2θ value 32.4º, 37.5º, 64.3º, and 67,5º. The FT-IR spectrum show vibration of CaO at wavenumber 354.9 cm-1. SEM-EDX data indicated the surface morphology calcium oxide of Portunus pelagicus more homogen than Portunus pelagicus before decomposition. The decomposition of CaO at 1000°C was applied in the syntesis of biodiesel from waste cooking oil, palm oil, and coconut oil. The biodiesel products have density 0.8621, 0.8725, and 0.8688 g/cm3. Viscosity are 5.27, 3.71, and 2.45 mm2/s(cst). Acid values respectively are 0.3069, 0.2423 and 0.2100 mg/KOH and Iodine numbers 39.48, 36.12 and 9.24 g I2/100g. All characteristic of biodiesel from waste cooking oil, palm oil, and coconut oil are agree with SNI standard. The best biodiesel product derived from coconut oil is agree to the parameter value of biodiesel standard.
Keywords: biodiesel. Portunus pelagicus. calcium oxide. catalyst
Thermal stability of polyoxometalate compound of Keggin K8[2-SiW11O39]∙nH2O supported with SiO2
Full text linkSynthesis through sol-gel method and characterization of polyoxometalate compound of K8[b2-SiW11O39]∙nH2O supported with SiO2 have been done. The functional groups of polyoxometalate compound was characterized by FT-IR spectrophotometer for the fungtional groups and the degree’s of crystalinity using XRD. The acidity of K8[b2-SiW11O39]∙nH2O/SiO2 was determined qualitative analysis using ammonia and pyridine adsorption and the quantitative analysis using potentiometric titration method. The results of FT-IR spectrum of K8[b2-SiW11O39]∙nH2O appeared at wavenumber 987.55 cm-1 (W=O), 864.11 cm-1 (W-Oe-W), 756.1 cm-1 (W-Oc-W), 3425.58 cm-1 (O-H), respectively and spectrum of K8[b2-SiW11O39]SiO2 appeared at wavenumber 956.69 cm-1 (W=O), 864.11 cm-1 (W-Oe-W), 3448.72 cm-1 (O-H), respectively. The diffraction of XRD pattern of K8[b2-SiW11O39]∙nH2O and K8[b2-SiW11O39]∙nH2O/SiO2 compounds show high crystalinity. The acidic properties showed K8[b2-SiW11O39]∙nH2O/SiO2 more acidic compared to K8[b2-The SiW11O39]∙nH2O. The qualitative analysis showed pyridine compound adsorbed more of polyoxometalate compound of K8[b2-SiW11O39]∙nH2O/SiO2. Analysis of stability showed that the K8[b2-SiW11O39]∙nH2O/SiO2 at temperature 500°C has structural changes compare to 200-400oC which was indicated from vibration at wavenumber 800-1000 cm-1.
Keywords : K8[b2-SiW11O39]∙nH2O, polyoxometalate, SiO2
Conversion of cyclohexane to cyclohexanol and cyclohexanone using H3[PMo12O40].nH2O-ZrOCl2 as catalyst
Full text linkSynthesis and preparation polyoxometalate compound H3[-PMo12O40].nH2O supported with ZrOCl2 at various weights of ZrOCl2 i.e. 0.25 g, 0.50 g, 0.75 g, 1.00 g, 1.25 g, 0.01 g and 0.05 g to form H3[-PMo12O40].nH2O/ZrOCl2 have been conducted. These compound than was characterized through functional group analysis using FT-IR spectrophotometer and XRD analysis. The results showed that the optimal preparation was H3[-PMo12O40].nH2O/ZrOCl2 with support 0.05 g. FT-IR spectrum of H3[-PMo12O40].nH2O/ZrOCl2 show wavenumber at 1033.85 cm-1 for vibration P-O, 887.26 cm-1 for vibration M=O, 840.96 cm-1 and 655.80 cm-1 for vibration Mo-O-Mo. The existence of support was identified at wavenumber 1404.18 cm-1for vibration Zr-OH and 478.35 for vibration Zr-O-Zr. XRD powder analysis showed that material H3[-PMo12O40].nH2O/ZrOCl2 was amorphous material. Material H3[-PMo12O40].nH2O/ZrOCl2 was applied in oxidation of cyclohexane using hydrogen peroxide as oxidant. Oxidation process was optimized through reaction time H2O2 amount, temperature and catalyst weight. The results showed that the highest conversion in the using of H3[-PMo12O40].nH2O/ZrOCl2 catalyst found at 2 hours reaction time, 3 mL H2O2, 80oC temperature and 0.038 g catalyst with conversion 99.18 %. Selectivity of best reaction was 6.96 % for cyclohexanol and 24.9% for cyclohexanone, which was identified by GC-MS.
Keywords : H3[-PMo12O40].nH2O-ZrO2,cyclohexane, cyclohexanol, cyclohexanone
