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All Journal Eksergi: Chemical Engineering Journal International Journal of Renewable Energy Development
Rochmadi Rochmadi
Universitas Gadjah Mada
Chemical Engineering, Chemistry & Bioengineering Control & Systems Engineering Earth & Planetary Sciences Electrical & Electronics Engineering Energy Engineering Industrial & Manufacturing Engineering Materials Science & Nanotechnology

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Chitosan Concentration and Cross-linker Volume Effect on The Release Kinetic of Red Ginger Oleoresin Microcapsule in Simulated Intestinal Fluid (SIF) Medium Jayanudin Jayanudin; Moh. Fahrurrozi; Sang Kompiang Wirawan; Rochmadi Rochmadi
Eksergi Vol 16, No 2 (2019)
Publisher : Prodi Teknik Kimia, Fakultas Teknologi Industri, UPN "Veteran" Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31315/e.v16i2.3088

Abstract

Red ginger oleoresin contains components that can be used as antioxidants. Release kinetics studies are used to provide doses to achieve the desired drug concentration. The purpose of this study was to determine the release kinetics of red ginger oleoresin microcapsules based on changes in chitosan concentration and volume of cross-linker and determine the diffusion coefficient of red ginger oleoresin through microcapsule walls. Red ginger oleoresin microcapsules were prepared from a mixture of red ginger oleoresin in chitosan solution and stirred to form an emulsion. After that, it was added to corn oil and stirred again to form a second emulsion. Glutaraldehyde saturated toluene was added dropwise after finished added the 25% glutaraldehyde solution and remains stirred for 2 hours. Red ginger oleoresin microcapsules were separated and washed with petroleum ether and hexane, then dried in an oven. Microcapsules inserted in the release medium (simulated intestinal fluid) without enzymes, and then the samples were analyzed using a UV-vis spectrophotometer to determine the absorbance. The release kinetics models used were zero order, first order, Higuchi, Korsmeyer-Peppas, and Hixon-Crowell. The highest correlation coefficient (R2) was obtained from the Korsmeyer-Peppas release kinetics model, R2 = 0.73-0.85 with the value of n = 0.39-0.41. Based on the n value, the release mechanism of red ginger oleoresin microcapsules was Fickian diffusion. The diffusion coefficients obtained were 2,807 x 10-13 - 3,675 x 10-13 cm2 /sec.
Thermal Decomposition and Kinetic Studies of Pyrolysis of Spirulina Platensis Residue Siti Jamilatun; Budhijanto Budhijanto; Rochmadi Rochmadi; Arief Budiman
International Journal of Renewable Energy Development Vol 6, No 3 (2017): October 2017
Publisher : Center of Biomass & Renewable Energy, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/ijred.6.3.193-201

Abstract

 Analysis of thermal decomposition and pyrolisis reaction kinetics of Spirulina platensis residue (SPR) was performed using Thermogravimetric Analyzer. Thermal decomposition was conducted with the heating rate of 10, 20, 30, 40 and 50oC/min from 30 to 1000oC. Thermogravimetric (TG), Differential Thermal Gravimetric (DTG), and Differential Thermal Analysis (DTA) curves were then obtained. Each of the curves was divided into 3 stages. In Stage I, water vapor was released in endothermic condition. Pyrolysis occurred in exothermic condition in Stage II, which was divided into two zones according to the weight loss rate, namely zone 1 and zone 2. It was found that gasification occurred in Stage III in endothermic condition. The heat requirement and heat release on thermal decomposition of SPR are described by DTA curve, where 3 peaks were obtained for heating rate 10, 20 and 30°C/min and 2 peaks for 40 and 50°C/min, all peaks present in Zone 2. As for the DTG curve, 2 peaks were obtained in Zone 1 for similar heating rates variation. On the other hand, thermal decomposition of proteins and carbohydrates is indicated by the presence of peaks on the DTG curve, where lignin decomposition do not occur due to the low lipid content of SPR (0.01wt%). The experiment results and calculations using one-step global model successfully showed that the activation energy (Ea) for the heating rate of 10, 20, 30, 40 and 50oC/min for zone 1 were 35.455, 41.102, 45.702, 47.892 and 47.562 KJ/mol, respectively, and for zone 2 were 0.0001428, 0.0001240, 0.0000179, 0.0000100 and 0.0000096 KJ/mol, respectively.Keywords: Spirulina platensis residue (SPR), Pyrolysis, Thermal decomposition, Peak, Activation energy.Article History: Received June 15th 2017; Received in revised form August 12th 2017; Accepted August 20th 2017; Available onlineHow to Cite This Article: Jamilatun, S., Budhijanto, Rochmadi, and Budiman, A. (2017) Thermal Decomposition and Kinetic Studies of Pyrolysis of Spirulina platensis Residue, International Journal of Renewable Energy Development 6(3), 193-201.https://doi.org/10.14710/ijred.6.3.193-201
Co-Authors Arief Budiman Budhijanto Budhijanto Jayanudin Jayanudin Moh. Fahrurrozi Sang Kompiang Wirawan Siti Jamilatun