Witri Wahyu Lestari
Chemistry Department, Faculty Of Mathematics And Natural Sciences, Sebelas Maret University, Jl. Ir. Sutami No. 36A, Kentingan, Jebres, Surakarta

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Fe/Indonesian Natural Zeolite as Hydrodeoxygenation Catalyst in Green Diesel Production from Palm Oil Riandy Putra; Witri Wahyu Lestari; Fajar Rakhman Wibowo; Bambang Heru Susanto
Bulletin of Chemical Reaction Engineering & Catalysis 2018: BCREC Volume 13 Issue 2 Year 2018 (August 2018)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.13.2.1382.245-255

Abstract

The Petroleum diesel-based fossil fuel remains the primary source of energy consumption in Indonesia. The utilization of this unrenewable fuel depletes fossil fuels; thus, an alternative, renewable fuel, such as one based on biohydrocarbon from biomass-green diesel-could be an option. In this work, green diesel was produced through the hydrodeoxygenation from palm oil and processed in a batch-stirred autoclave reactor over natural zeolite (NZ) and NZ modified with 3 wt.% Fe metal (Fe/NZ) as heterogeneous catalyst. NZ showed high crystallinity and suitability to the simulated pattern of the mordenite and clinoptilolite phases according to X-ray diffraction (XRD) analysis. The presence of Fe metal was further confirmed by XRD, with an additional small diffraction peak of Fe0 that appeared at 2θ = 44-45°. Meanwhile, NZ and Fe/NZ were also characterized by Scanning electron microscopy (SEM) with Energy Dispersive X-ray (EDX), X-ray Fluorescence (XRF), and Surface Area Analyzer (SAA). The obtained materials were tested for the conversion of palm oil into diesel-range hydrocarbons (C15-C18) under conditions of 375 °C and 12 bar H2 for 2 h. NZ and Fe/NZ produced a liquid hydrocarbon with straight-chain (C15-C18) alkanes as the most abundant products. Based on Gas Chromatography-Mass Spectrometry (GC-MS) measurement, a higher conversion of palm oil into diesel-like hydrocarbons reached more than 58% and 89%, when NZ and Fe modified NZ (Fe/NZ), respectively were used as catalysts. 
Enhanced Hydrogen Storage Capacity Over Electro-synthesized HKUST-1 Witri Wahyu Lestari; Marisa Adreane; Hadi Suwarno
Journal of Mathematical and Fundamental Sciences Vol. 49 No. 3 (2017)
Publisher : Institute for Research and Community Services (LPPM) ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.math.fund.sci.2017.49.3.1

Abstract

HKUST-1 [Cu3(1,3,5-BTC)2] (BTC = 1,3,5-benzene-tri-carboxylate) was synthesized using an electrochemical method and tested for hydrogen storage. The obtained material showed a remarkably higher hydrogen uptake over reported HKUST-1 and reached until 4.75 wt% at room temperature and low pressure up to 1.2 bar. This yield was compared to HKUST-1 obtained from the solvothermal method, which showed a hydrogen uptake of only 1.19 wt%. Enhancement of hydrogen sorption of the electro-synthesized product was due to the more appropriate surface area and pore size, effected by the preferable physical interaction between the hydrogen gasses and the copper ions as unsaturated metal centers in the frameworks of HKUST-1.
Lithium Titanate (LTO) Synthesis Through Solid State Reaction and Its Performance for LiFePO4/LTO Battery Viona Natalia; Anggia Putri Gustami; Fitria Rahmawati; Witri Wahyu Lestari; Agus Purwanto
Journal of Mathematical and Fundamental Sciences Vol. 50 No. 3 (2018)
Publisher : Institute for Research and Community Services (LPPM) ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.math.fund.sci.2018.50.3.5

Abstract

Lithium titanate, LTO, was synthesized by solid state reaction with Li2CO3 and TiO2 powder as precursors. The result was characterized to investigate its crystal structure, phase content, cell parameters, surface morphology, electrical conductivity and its performance as electrode in a lithium ion battery. XRD analysis with Le Bail refinement showed that the prepared materials consisted of 4 phases of Li4Ti5O12, Li2TiO3, anatase TiO2 and rutile TiO2. The surface morphology was still not homogeneous, with an average grain size of 0.533 ± 0.157 µm. When 1% LTO was mixed with graphite and used as anode of an LFP battery, it produced a specific capacity of 130.66 mAhg"‘1 with Coulombic efficiency of 94.2%. When the composition was 5% of the total anode powder, the specific capacity was 118.74 mAhg-1 and Coulombic efficiency was 92.72%.
Fe/Indonesian Natural Zeolite as Hydrodeoxygenation Catalyst in Green Diesel Production from Palm Oil Riandy Putra; Witri Wahyu Lestari; Fajar Rakhman Wibowo; Bambang Heru Susanto
Bulletin of Chemical Reaction Engineering & Catalysis 2018: BCREC Volume 13 Issue 2 Year 2018 (August 2018)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.13.2.1382.245-255

Abstract

The Petroleum diesel-based fossil fuel remains the primary source of energy consumption in Indonesia. The utilization of this unrenewable fuel depletes fossil fuels; thus, an alternative, renewable fuel, such as one based on biohydrocarbon from biomass-green diesel-could be an option. In this work, green diesel was produced through the hydrodeoxygenation from palm oil and processed in a batch-stirred autoclave reactor over natural zeolite (NZ) and NZ modified with 3 wt.% Fe metal (Fe/NZ) as heterogeneous catalyst. NZ showed high crystallinity and suitability to the simulated pattern of the mordenite and clinoptilolite phases according to X-ray diffraction (XRD) analysis. The presence of Fe metal was further confirmed by XRD, with an additional small diffraction peak of Fe0 that appeared at 2θ = 44-45°. Meanwhile, NZ and Fe/NZ were also characterized by Scanning electron microscopy (SEM) with Energy Dispersive X-ray (EDX), X-ray Fluorescence (XRF), and Surface Area Analyzer (SAA). The obtained materials were tested for the conversion of palm oil into diesel-range hydrocarbons (C15-C18) under conditions of 375 °C and 12 bar H2 for 2 h. NZ and Fe/NZ produced a liquid hydrocarbon with straight-chain (C15-C18) alkanes as the most abundant products. Based on Gas Chromatography-Mass Spectrometry (GC-MS) measurement, a higher conversion of palm oil into diesel-like hydrocarbons reached more than 58% and 89%, when NZ and Fe modified NZ (Fe/NZ), respectively were used as catalysts.