Anis Kristiani

Catalytic conversion of ethanol to aromatic compounds using metal/zeolite catalysts

Catalytic conversion of ethanol into aromatic compounds was investigated by transition metal supported on zeolite catalyst. The catalysts were prepared by impregnation method with a variation of transition metals that consist of Zn/zeolite, Cu/zeolite and Co/zeolite. Catalyst characterization was performed by X-ray diffraction (XRD) analysis, surface area analysis (BET and BJH methods), acidity analysis with the gravimetric method, FTIR spectroscopy and thermal gravimetric analysis (TGA). The reaction of ethanol to aromatic compounds was conducted in fixed bed reactor at 350 °C and atmospheric pressure. Zn/zeolite catalyst gave the highest aromatic content around 97.39% (v/v) and the highest selectivity toward ethylbenzene.

Preparation of Sulfated Zirconia Using Modified Sol Gel Method

A series of sulfated zirconia was prepared through sol gel method in alcohol medium. Porosity of the catalyst was developed in two different methods, which were immersion of cetyltrimethyl ammonium chloride (CTAC) surfactant as templating agent and Supercritical Fluid Extraction (SFE). The physico-chemical properties of the catalysts were characterized by Thermal Gravimetric-Differential Thermal Analysis (TG-DTA), X-ray Diffraction (XRD), Brunauer-Emmett-Teller (BET) and Barret-Joyner-Halenda (BJH) and gravimetry method for acidity measurement following by the adsorption of organic bases. The characterization results show that different method of immersing CTAC surfactant and SFE affecting physical and chemical properties, i.e. crystalinity, surface area, pore size, pore volume and acidity.

The Potency of Fenton-Polyaluminum Chloride for Black Liquor Treatment

Black liquor is one of the main by-products of the pretreatment process in bioethanol production from empty oil palm fruit bunches, with a high chemical oxygen demand (COD) and low dissolved oxygen (DO). The effect of FeSO4 as a coagulant and FeSO4–H2O2 for Fenton on the degradation of black liquor was examined. This study also identified the ability of a fungus to decolorize black liquor wastewater after the Fenton process and on original black liquor. One percent ferrous sulfate decolorized 84% of black liquor with a concentration of 30,000 ppm under the coagulation method. By adding H2O2 and FeSO4 through the Fenton process, decolorization of the original black liquor was approximately 52%. Combining Fenton and polyaluminum chloride decolorized black liquor up to 90% in 33 min, whereas Coriolus versicolor decolorized 54% and 75% Fenton-treated black liquor and original black liquor after 15 days, respectively.

Hydrogenation of citral into its derivatives using heterogeneous catalyst

Citral as known as a monoterpene can be found in plants and citrus fruits. The hydrogenation of citral into its derivatives become interesting area for scientist. This compound and its derivatives can be used for many application in pharmaceuticals and food areas. The development of heterogeneous catalysts become an important aspect in catalytic hydrogenation citral process. Nickel supported catalysts are well known as hydrogenation catalyst. These heterogeneous catalysts were tested their catalytic activity in hydrogenation of citral. The effect of various operation conditions, in term of feed concentration, catalyst loading, temperature, and reaction time were also studied. The liquid products produced were analyzed by using Gas Chromatography-Mass Spectroscopy (GC-MS). The result of catalytic activity tests showed nickel skeletal catalyst exhibits best catalytic activity in hydrogenation of citral. The optimum of operation condition was achieved in citral concentration 0.1 M with nickel skeletal cataly...

Hydrogenation of artemisinin to dihydroartemisinin over heterogeneous metal catalysts

A series of heterogeneous metal catalysts of Ni, Pd, and Pt, both of synthesized and commercial catalysts were used for hydrogenation of artemisinin to dihydroartemisinin. Their catalytic properties were determsined by Surface Area Analyzer and Thermogravimetry Analyzer. The catalytic properties in various reaction conditions in terms of temperature, pressure, reaction time and reactant/catalyst ratio were also studied. The results catalytic activity tests showed that synthesized catalysts of Ni/zeolite, Ni-Sn/zeolite, Ni/bentonite and Ni-Sn/bentonite were not able to produced dihydroartemisinin and deoxyartemisinin was mainly formed. Meanwhile, commercial catalysts of Ni skeletal, Pd/activated charcoal and Pt/activated charcoal yielded the desired dihydroartemisinin product. Ni skeletal commercial catalyst gave the best performance of hydrogenation artemisinin to dihydroartemisinin in room temperature and low H2 pressure.

Potential of oil palm empty fruit bunches for bioethanol production and application of chemical methods in bioethanol wastewater treatment : OPEFB for bioethanol and its wastewater treatment

Lignocellulosic-based bioethanol is providing one window of potential alternative energy. Pretreatment is one of the steps in the bioconversion of lignocellulosic material. The pretreatment process was conducted in a 5-liter reactor at 150 °C, 4 bars of pressure during 30 minutes. The SSF was carried out using 30 FPU cellulase enzyme and yeast Saccharomyces cerevisiae. The delignification of pretreatment reached 64.58%. The ethanol production after SSF process reached 62 gl−1. The black liquor wastewater can be effectively treated by using chemical methods consist of coagulation-flocculation, Fenton, and adsorption. These processes have able to remove COD, TSS, and color more than 80%.