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Wega Trisunaryanti
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Yogyakarta 55281
Chemical Engineering, Chemistry & Bioengineering Chemistry

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KINETICS STUDY ON NITRATION OF METHYL RICINOLEATE Abdullah Abdullah; Triyono Triyono; Wega Trisunaryanti; Winarto Haryadi
Indonesian Journal of Chemistry Vol 12, No 2 (2012)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (303.653 KB) | DOI: 10.22146/ijc.21351

Abstract

Kinetics parameter values of methyl ricinoleate nitration (rate constant, reaction order and the rate of reaction) have been determined. Nitration was carried out with both concentrations of HNO3 and acetic anhydride in excess to the concentration of methyl ricinoleate. Thus, the kinetics parameter value was only affected by the concentration of methyl ricinoleate. Based on kinetic study conducted, it could be concluded that the nitration follows pseudo first-order, and the reaction rate for methyl ricinoleate with initial concentration of 0.375, 0.325 and 0.250 M were 3.736 x 10-5, 2.471 x 10-5, and 1.724 x 10-5 M/s respectively, with the rate constant at 28 °C was 6.667 x 10-4 (s-1). Based on evaluation of FTIR spectra could be estimated that the nitration produces compounds containing functional groups of -NO3 and -NO2.
CATALYTIC HYDROCRACKING OF WASTE LUBRICANT OIL INTO LIQUID FUEL FRACTION USING ZnO, Nb2O5, ACTIVATED NATURAL ZEOLITE AND THEIR MODIFICATION Wega Trisunaryanti; Suryo Purwono; Arista Putranto
Indonesian Journal of Chemistry Vol 8, No 3 (2008)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (957.446 KB) | DOI: 10.22146/ijc.21589

Abstract

Catalytic hydrocracking of waste lubricant oil into liquid fuel fraction using ZnO, Nb2O5, activated natural zeolite (ZAAH) and their modification has been investigated. The zeolite was produced in Wonosari, Yogyakarta. Activation of the zeolite was carried out by refluxing with HCl 3M for 30 min, produced the activated natural zeolite (ZAAH). The ZnO/ZAAH catalyst was prepared by impregnation of Zn onto the ZAAH by ion exchange method using salt precursor of Zn(NO3)2.4H2O. The Nb2O5/ZAAH catalyst was prepared by mixing the ZAAH sample with Nb2O5 and oxalic acid solution until the paste was formed. The impregnation of Zn onto Nb2O5/ZAAH was carried out using the same method to that of the ZnO/ZAAH catalyst resulted ZnO/Nb2O5-ZAAH catalyst. Characterization of catalyst includes determination of Zn metal by Atomic Absorption Spectroscopy (AAS), acidity by gravimetric method and catalyst porosity by Surface Area Analyzer (NOVA-1000). Catalytic hydrocracking was carried out in a semi-batch reactor system using ZnO, ZAAH, ZnO/ZAAH and ZnO/Nb2O5-ZAAH catalysts at 450 oC under the H2 flow rate of 15 mL/min. and the ratio of catalyst/feed = 1/5. The composition of liquid products was analyzed by Gas Chromatograpy (GC).The results showed that impregnation of ZnO and/or Nb2O5 on the ZAAH increased the acidity and specific surface area of catalyst. The products of the hydrocracking process were liquid, coke and gas. Conversion of liquid products was increased by the increase of catalyst acidity. The highest liquid product was produced by ZnO/Nb2O5-ZAAH catalyst, 52.97 wt-%, consist of gasoline, 38.87 wt-% and diesel, 14.10 wt-%.
EFFECT OF CERIUM ON HYDRODESULFURIZATION CATALYST PERFORMANCE Triyono Triyono; Wega Trisunaryanti
Indonesian Journal of Chemistry Vol 8, No 1 (2008)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (734.774 KB) | DOI: 10.22146/ijc.21648

Abstract

Effect of cerium on hydrodesulfurization catalysts performance have been investigated. The catalysts were Pt or Pt-Ce supported on zeolite. The Pt/Zeolite catalyst was prepared by wet impregnation method, while that of Pt-Ce/Zeolite catalyst was prepared using coimpregnation method both were followed by drying, calcination, oxidation and reduction. The catalysts activity test was performed in a micro reactor and products composition was determined using gas chromatography. The results showed that cerium enhanced catalyst performance especially catalyst lifetime. Therefore, the catalysts have higher tendency to remain active for longer period. Due to its function, cerium might be used as a promoter of hydrodesulfurization catalysts.
Co-Authors Abdullah Abdullah Arista Putranto Suryo Purwono Triyono Triyono Winarto Haryadi