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Characteristics of Oxidative Storage Stability of Canola Fatty Acid Methyl Ester Stabilised with Antioxidants Tirto Prakoso; Parncheewa Udomsap; Akiko Tanaka; Toshihiro Hirotsu; Shinichi Goto
Journal of Engineering and Technological Sciences Vol. 44 No. 3 (2012)
Publisher : Institute for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/itbj.eng.sci.2012.44.3.7

Abstract

The  storage  effects  on  the  oxidation  characteristics  of  fatty  acid methyl ester of canola oil (CME) were investigated  in this study.CME stabilised with  two  antioxidants, i.e.2,6-di-tert-bytyl-p-cresol  (BHT) and 6,6-di-tert-butyl-2, 2'-methylendi-p-cresol  (BPH),  was  stored at 20, 40 and  60°C.The  oxidation stability data  were measured  by  the  Rancimat test  method and  it was  found  that both BHT and BPH  addition increased  the oxidation resistance of  the  CME.  The results showed that when BPH or BHT was added at a concentration of 100 ppm, the oxidation induction period of the neat CME samples increased from 5.53 h to 6.93  hand  6.14 h,  respectively.  Comparing both antioxidants,  BPH  proved to be more  effective  in  increasing  the  oxidation  resistance  when  both  antioxidants were added at the same concentration.  Furthermore, the oxidation induction timedecreased  linearly  with  the  storage  time.  It  was  shown  that  the  oxidation occurred  rapidly  in  the  first  8  weeks  of  storage.  Later,  a  kinetic  study  was undertaken  and  first-order  kinetics  were  applied  to  explain  the  oxidation characteristics of  the  CME added with antioxidants. This kinetic study focused on  exploiting  the  activation  energy  values  obtained  from  the  Arrheniusequations. Also, the  oxidation effects on  other  quality parameters, including acid value, peroxide value, kinematic viscosity, and water content, were examined.
Catalytic and Thermal Decarboxylation of Mg-Zn Basic Soap to Produce Drop-in Fuel in Diesel Boiling Ranges Godlief F. Neonufa; Tatang H. Soerawidjaja; Tirto Prakoso
Journal of Engineering and Technological Sciences Vol. 49 No. 5 (2017)
Publisher : Institute for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2017.49.5.2

Abstract

Fatty acid deoxygenation is a method for producing renewable hydrocarbon fuels such as green diesel, jet biofuel and biogasoline. In the present commercial method, deoxygenation is directly applied to vegetable oils through liquid phase hydrotreatment. This method is expensive because it consumes a large amount of hydrogen and requires severe operating conditions. The objective of this study was the production of a diesel-like hydrocarbon fuel that can be considered as drop-in replacement for petroleum-based diesel fuels, by catalytic thermal decarboxylation of Mg-Zn basic soap. In particular, this study investigated the decarboxylation of Mg-Zn basic soap at low temperature and pressure, without external supply of hydrogen. The Mg-Zn basic soap (9/1 mole ratio of Mg/Zn) was derived from palm stearin and decarboxylated at 350 °C and atmospheric pressure for 5 hours. The basic soap effectively decarboxylated, yielding a diesel-like hydrocarbon fuel with a liquid product yield of 62%-weight. The resulting hydrocarbon product is a complex mixture consisting of normal paraffins in the range of carbon chain length C8"“C19, iso-paraffins and various olefin products.
Comparative Study of Nyamplung (Callophylum inophyllum) Kernel Oil Obtained from Mechanical and Chemical Extraction for Biofuel Production Hanifah Widiastuti; Meiti Pratiwi; Godlief F. Neonufa; Tatang Hernas Soerawidjaja; Tirto Prakoso
Jurnal Rekayasa Proses Vol 13, No 2 (2019)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (329.394 KB) | DOI: 10.22146/jrekpros.42816

Abstract

Nyamplung (Callophylum inophyllum) contains oil around 40-73% in its seed. It has recently gained recognition as a potential source for biofuel production. The oil recovery process from renewable sources such as nyamplung is widely carried out by using chemical extraction with solvents. Nevertheless, this method is considered costly and there are safety issues as well as environmental concerns related to the solvents used. Therefore, mechanical extraction has emerged as an alternative method. In this study, the nyamplung oil recovered by mechanical extraction via hydraulic press and chemical extraction utilizing Soxhlet extraction was compared. Soxhlet extraction was carried out by using n-hexane as a solvent with a temperature of 70 oC for 5 hours. Before the extraction process, the kernel was initially pretreated to reduce the particle sizes and the water content. The results show that the oil yield recovered using the hydraulic press is 58%, which is comparable with the value obtained from Soxhlet extraction (65%). The oil characteristics were also compared, and the profiling shows no significant difference in the properties (saponification value, acid value, and iodine value) of oils recovered using both methods. The composition of fatty acids was also analyzed for utilization as a biofuel feedstock. Higher content of oleic acid was observed in oil resulted from chemical extraction while mechanical extraction yielded oil with higher palmitic acid content.A B S T R A KNyamplung (Callophylum inophyllum) mengandung minyak sebesar 40-73% dalam bijinya dan belakangan ini diakui sebagai sumber potensial untuk pembuatan biofuel. Proses perolehan minyak nabati dari biji nyamplung pada umumnya dilakukan menggunakan ekstraksi kimia dengan pelarut. Akan tetapi, metode ini cenderung berbiaya tinggi serta memiliki isu berkaitan dengan keselamatan proses dan dampak lingkungan berkaitan dengan penggunaan pelarut. Oleh karena itu, metode ekstraksi mekanis banyak dikembangkan sebagai alternatif metode ekstraksi minyak. Dalam penelitian ini, hasil perolehan minyak nyamplung melalui penekanan hidrolik dibandingkan dengan hasil dari ekstraksi Soxhlet. Ekstraksi Soxhlet dilakukan dengan pelarut n-heksana pada suhu 70 oC selama 5 jam. Sebelum proses ekstraksi, biji nyamplung mengalami perlakuan awal terlebih dahulu dengan cara digiling untuk mengurangi ukuran biji dan dipanaskan untuk mengurangi kadar air. Hasil yang diperoleh menunjukkan bahwa yield minyak dari ektraksi mekanik sebesar 58% sementara yield dari ekstraksi Soxhlet adalah 65%. Karakteristik minyak yang dihasilkan melalui kedua metode ini tidak menunjukkan perbedaan yang signifikan dalam hal nilai saponifikasi, nilai asam, dan nilai iodine. Analisis komposisi asam lemak dari kedua minyak yang dihasilkan menunjukkan bahwa minyak yang diperoleh dari ekstraksi kimia mengandung asam oleat dengan persentase yang lebih tinggi sementara minyak dari hasil ekstraksi mekanik memiliki persentase asam palmitat yang lebih tinggi.
Performance of Various Organic Solvents as Reaction Media in Plant Oil Lipolysis with Plant Lipase Astri Nur Istyami; Tatang Hernas Soerawidjaja; Tirto Prakoso; Tri Ari Penia Kresnowati
Reaktor Volume 18 No. 2 June 2018
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (651.652 KB) | DOI: 10.14710/reaktor.18.2.71-75

Abstract

Fatty acids are intermediate substances in synthesis of oleochemical products. Enzymatic technology of fatty acids production (also known as lipolysis) is now developing as potential substitution for the conventional production of fatty acid, i.e. thermal hydrolysis of triglyceride. It offers more economical process condition, low energy consumption, and minimal product degradation compared to the conventional process. This research aims to evaluate performance of various organic solvents as reaction media in lipolysis with plant latex lipase. Organic solvents observed were chloroform, n-hexane, diethyl ether, benzene, acetone, ethanol, methanol, n-heptane, and isooctane. Analysis of each organic solvent effect on lipolysis was described based on solvents properties. Conversion of lipolysis with organic solvents is 0,10-1,25 times fold compared to conversion of non-solvent lipolysis. We suggest that dielectric constant and viscosity are the two main organic solvent properties affecting lipase performance in lipolysis. Overall, n-hexane, n-heptane, and isooctane are recommended to be used as reaction media in lipolysis with plant lipase because their effects to degree of lipolysis are positive.  Keywords: lipolysis; lipase; organic solvent; frangipani
Production of Biogasoline via Pyrolysis of Oleic Acid Basic Soaps Endar Puspawiningtiyas; Tirto Prakoso; Meiti Pratiwi; Subagjo Subagjo; Tatang Hernas Soerawidjaja
Journal of Engineering and Technological Sciences Vol. 54 No. 3 (2022)
Publisher : Directorate for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2022.54.3.11

Abstract

In this study, an investigation on the effect of the Ca/Mg/Zn mixing ratio on gasoline-range hydrocarbon production by oleic basic soap pyrolysis was carried out. The ratios of calcium to magnesium used were 15%, 35%, 50%, 65%, and 85% with constant Zn. Oleic basic soap was obtained by saponification with the modified fusion method. Pyrolysis experiments were carried out at 450 °C using a semi-continuous reactor with a feed flow rate of 5 g/15 min. The process produced three fractions, i.e., gas, solid, and liquid (bio-hydrocarbon + water). The gas products were characterized by GC-TCD, and the results showed the presence of carbon dioxide, hydrogen, nitrogen, oxygen, and methane. Based on the GC-FID and FT-IR results, the bio-hydrocarbon comprised mainly homologous hydrocarbon from carbon number C7 to C19 containing n-alkanes, alkenes, various iso-alkanes, and some oxygenated compounds. All calcium ratios in the oleic basic soap produced hydrocarbon in the range of gasoline (C7-C11) as the dominant product. The maximum yield of gasoline (74.86%) was achieved at 15% calcium.
KARBONISASI LIMBAH KELAPA SAWIT DENGAN PROSES HIDROTERMAL SEBAGAI BAHAN BAKU ELEKTRODA SUPERKAPASITOR Tantra Diwa Larasati; Tirto Prakoso; Jenny Rizkiana
Jurnal Chemurgy Vol 5, No 1 (2021): Jurnal Chemurgy-Juni 2021
Publisher : Universitas Mulawarman

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30872/cmg.v5i1.5916

Abstract

Limbah kelapa sawit merupakan sumber biomassa yang melimpah di Indonesia. Ketersediaan biomassa kelapa sawit ini dapat dimanfaatkan sebagai bahan baku produk bernilai tambah tinggi. Salah satu produk yang dapat dihasilkan adalah karbon aktif. Karbon aktif merupakan material berpori dan memiliki konduktivitas yang baik, membuat karbon aktif cocok digunakan sebagai material elektroda superkapasitor. Karbon aktif dibuat melalui dua proses utama yaitu karbonisasi dan aktivasi. Proses karbonisasi yang dilakukan adalah karbonisasi hidrotermal dilanjutkan dengan aktivasi secara fisika. Penelitian ini difokuskan pada pembuatan karbon aktif berbasis limbah kelapa sawit dengan proses karbonisasi hidrotermal untuk bahan baku superkapasitor. Mesopore area dari karbon aktif terbentuk akibat penggunaan CaCl2 sebagai agen pengaktivasi selama proses hidrotermal. Karbon aktif yang dihasilkan dari tandan kosong kelapa sawit memiliki luas permukaan 375 – 723 m2/g dan ukuran pori 3,4 – 5,6 nm. Pada penelitian ini, karbon aktif digunakan sebagai elektroda kerja pada superkapasitor tipe hybrid simetrikal. Sel superkapasitor ini mampu menghasilkan kapasitansi sebesar 4,3015 F/g.
Comparative Study of Nyamplung (Callophylum inophyllum) Kernel Oil Obtained from Mechanical and Chemical Extraction for Biofuel Production Hanifah Widiastuti; Meiti Pratiwi; Godlief F. Neonufa; Tatang Hernas Soerawidjaja; Tirto Prakoso
Jurnal Rekayasa Proses Vol 13, No 2 (2019)
Publisher : Departemen Teknik Kimia Fakultas Teknik Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (329.394 KB) | DOI: 10.22146/jrekpros.42816

Abstract

Nyamplung (Callophylum inophyllum) contains oil around 40-73% in its seed. It has recently gained recognition as a potential source for biofuel production. The oil recovery process from renewable sources such as nyamplung is widely carried out by using chemical extraction with solvents. Nevertheless, this method is considered costly and there are safety issues as well as environmental concerns related to the solvents used. Therefore, mechanical extraction has emerged as an alternative method. In this study, the nyamplung oil recovered by mechanical extraction via hydraulic press and chemical extraction utilizing Soxhlet extraction was compared. Soxhlet extraction was carried out by using n-hexane as a solvent with a temperature of 70 oC for 5 hours. Before the extraction process, the kernel was initially pretreated to reduce the particle sizes and the water content. The results show that the oil yield recovered using the hydraulic press is 58%, which is comparable with the value obtained from Soxhlet extraction (65%). The oil characteristics were also compared, and the profiling shows no significant difference in the properties (saponification value, acid value, and iodine value) of oils recovered using both methods. The composition of fatty acids was also analyzed for utilization as a biofuel feedstock. Higher content of oleic acid was observed in oil resulted from chemical extraction while mechanical extraction yielded oil with higher palmitic acid content.A B S T R A KNyamplung (Callophylum inophyllum) mengandung minyak sebesar 40-73% dalam bijinya dan belakangan ini diakui sebagai sumber potensial untuk pembuatan biofuel. Proses perolehan minyak nabati dari biji nyamplung pada umumnya dilakukan menggunakan ekstraksi kimia dengan pelarut. Akan tetapi, metode ini cenderung berbiaya tinggi serta memiliki isu berkaitan dengan keselamatan proses dan dampak lingkungan berkaitan dengan penggunaan pelarut. Oleh karena itu, metode ekstraksi mekanis banyak dikembangkan sebagai alternatif metode ekstraksi minyak. Dalam penelitian ini, hasil perolehan minyak nyamplung melalui penekanan hidrolik dibandingkan dengan hasil dari ekstraksi Soxhlet. Ekstraksi Soxhlet dilakukan dengan pelarut n-heksana pada suhu 70 oC selama 5 jam. Sebelum proses ekstraksi, biji nyamplung mengalami perlakuan awal terlebih dahulu dengan cara digiling untuk mengurangi ukuran biji dan dipanaskan untuk mengurangi kadar air. Hasil yang diperoleh menunjukkan bahwa yield minyak dari ektraksi mekanik sebesar 58% sementara yield dari ekstraksi Soxhlet adalah 65%. Karakteristik minyak yang dihasilkan melalui kedua metode ini tidak menunjukkan perbedaan yang signifikan dalam hal nilai saponifikasi, nilai asam, dan nilai iodine. Analisis komposisi asam lemak dari kedua minyak yang dihasilkan menunjukkan bahwa minyak yang diperoleh dari ekstraksi kimia mengandung asam oleat dengan persentase yang lebih tinggi sementara minyak dari hasil ekstraksi mekanik memiliki persentase asam palmitat yang lebih tinggi.
Design, Fabrication, and Testing of Supercapacitor Based on Nanocarbon Composite Material Heri rustamaji Rustamaji; Tirto Prakoso; Hary Devianto; Pramujo Widiatmoko; Isdiriayani Nurdin
ASEAN Journal of Chemical Engineering Vol 22, No 1 (2022)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ajche.70139

Abstract

This research investigates the design, fabrication, and testing of single-cell and module supercapacitors. The supercapacitor consists of carbon nanocomposites, which contain activated carbon (AC), multiwall carbon nanotubes (MWCNT), and graphene (GR). The coin and pouch cell type supercapacitors were manufactured with AC: MWCNT: GR composite electrodes in a ratio of 70:20:10 weight percent. Meanwhile, the electrochemical characterization showed that the highest capacitance values for single coin and pouch cells were 32.13 F g-1 and 5.3 F g-1, respectively, in 6 M KOH electrolyte at a scan rate of 2 mV s-1. Furthermore, the power and energy densities for the coin-cell supercapacitor were 69 W kg-1 and 6.6 Wh kg-1, respectively, while for the pouch cell, it was 7.4 W kg-1 and 1.0 Wh kg-1, respectively. The coin-cell supercapacitor durability test was carried out for 1000 cycles, yielding the retention capacitance and coulombic efficiency values of 94-97% and 100%, respectively. These results showed that the performance of the supercapacitor is close to commercial products. 
The Effect of Adding Mg-Zn/Al Hydrotalcite on the Decarboxylation Product of Hydroxy Pelargonate Soap Ella Melyna; Tirto Prakoso; Tatang Hernas Soerawidjaja
Fluida Vol 16 No 1 (2023): FLUIDA
Publisher : Department of Chemical Engineering, Politeknik Negeri Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35313/fluida.v16i1.4502

Abstract

Pelargonic acid is a by-product of the ozonolysis reaction of oleic acid to azelic acid. Pelargonic acid decarboxylation is the process of removing a carboxyl group (-COO-) from pelargonic acid (C9H18O2) to produce n-octane (C8H18) hydrocarbons, which are the main group of hydrocarbons that make up gasoline. The main parameter in gasoline is the octane number. The octane number of n-octane (C8H18) is 15, which is considered low, while good gasoline is desired to have a high octane number. To convert straight-chain alkanes and alkenes into branched alkanes and alkenes, an isomerization process can be carried out on vapor-cracking products using a solid catalyst. Transition metals and their compounds can be used as catalysts. Transition metals are able to change the oxidation state, create complex compounds, absorb other substances on the metal surface, and activate these substances. The transition metals used in this study are Zn and Al. The stages of the research process were the preparation of Mg-Zn/Al hydrotalcite base, the manufacturing of hydroxy pelargonate soap, and the decarboxylation of hydroxy pelargonate soap. The results of this study found that the highest product gain, namely 64.76%, occurred when Mg-Zn/Al = 5:5:2 hydrotalcite was in 300% excess. The highest product selectivity to 2.16% n-octane occurred in the use of a 300% excess of Mg-Zn/Al = 3:3:2 hydrotalcite. A low Al/Mg/Zn ratio of 2:10 can increase product yield; a high Al/Mg/Zn ratio of 2:6 can increase product selectivity and lower the freezing point.
Comparative study of nyamplung (Callophylum inophyllum) kernel oil obtained from mechanical and chemical extraction for biofuel production Hanifah Widiastuti; Meiti Pratiwi; Godlief F. Neonufa; Tatang H. Soerawidjaja; Tirto Prakoso
Jurnal Rekayasa Proses Vol 13 No 2 (2019): Volume 13, Number 2, 2019
Publisher : Jurnal Rekayasa Proses

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jrekpros.42816

Abstract

Nyamplung (Callophylum inophyllum) contains oil around 40-73% in its seed. It has recently gained recognition as a potential source for biofuel production. The oil recovery process from renewable sources such as nyamplung is widely carried out by using chemical extraction with solvents. Nevertheless, this method is considered costly and there are safety issues as well as environmental concerns related to the solvents used. Therefore, mechanical extraction has emerged as an alternative method. In this study, the nyamplung oil recovered by mechanical extraction via hydraulic press and chemical extraction utilizing Soxhlet extraction was compared. Soxhlet extraction was carried out by using n-hexane as a solvent with a temperature of 70 oC for 5 hours. Before the extraction process, the kernel was initially pretreated to reduce the particle sizes and the water content. The results show that the oil yield recovered using the hydraulic press is 58%, which is comparable with the value obtained from Soxhlet extraction (65%). The oil characteristics were also compared, and the profiling shows no significant difference in the properties (saponification value, acid value, and iodine value) of oils recovered using both methods. The composition of fatty acids was also analyzed for utilization as a biofuel feedstock. Higher content of oleic acid was observed in oil resulted from chemical extraction while mechanical extraction yielded oil with higher palmitic acid content.