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Comparative analysis between pyrolysis products of Spirulina platensis biomass and its residues Jamilatun, Siti; Budhijanto, B.; Rochmadi, R.; Yuliestyan, Avido; Hadiyanto, H.; Budiman, Arief
International Journal of Renewable Energy Development Vol 8, No 2 (2019): July 2019
Publisher : Center of Biomass & Renewable Energy, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/ijred.8.2.133-140

Abstract

Today’s needs of energy are yet globally dominated by fossil energy sources, causing the depletion of non-renewable energy. Alternatively, a potential substitute is the energy of biomass. Spirulina platensis (SP) is a microalgae biomass which, if extracted, will produce solid waste called Spirulina platensis residue (SPR). This research explores the pyrolysis product, produced within the range of 300 – 600 ºC, from the pyrolysis of SP and SPR using fixed bed reactors. The influence of temperature on pyrolysis product’s yield and characteristics are investigated by using mass balance method and gas chromatography – mass spectrometry (GC-MS) technique, respectively. The results from mass balance method present an optimum pyrolysis temperature of 550 ºC to obtain the desired liquid product of bio-oil, presenting the percentage of 34.59 wt.% for SP and 33.44 wt.% for SPR case. Additionally, with the increasing temperature, the char yield decreases for about 30 wt.% and the yield of gas seems to sharp increase from 550 to 600 ºC. These tendencies are both applied for SP and SPR source pyrolysis product. Interestingly, the benefit use as fossil fuel substitute might be derived, thanks to high HHV at the bio-oil product (32.04 MJ/kg for SP and 25.70 MJ/kg for SPR) and also at the char product with of 18.85-26.12 MJ/kg for both cases. The additional benefit come from the high content of C in its char product (50.31 wt.% for SPR and 45.26 wt.% for SP) that might be able to be used as an adsorbent, soil softener or other uses in the pharmaceutical field. ©2019. CBIORE-IJRED. All rights reserved
Influence of Particle Size and Chemical Activation on Rice Husk Biochar as Slow Release Fertilizer Natasha Amelia Rigitha Akhwan; Avido Yuliestyan
Eksergi Vol 17, No 2 (2020)
Publisher : Prodi Teknik Kimia, Fakultas Teknologi Industri, UPN "Veteran" Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31315/e.v17i2.3730

Abstract

Nitrogen, Phosphate, and Potassium are important nutritional elements contained in the fertilizers for plants but their presence in the soil could be easily wash out by rain water. Biochar, originated from rice husks with a high absorbance ability, might be able to be used to inhibit the release of those nutrients. This research aims to investigate the influence of biochar size and the HCl chemical activation. Biochar, which has been pyrolyzed, was ground and sieved to obtain powder with the size average equivalent to 0.2735 mm; 0.4485 mm; 0.725mm; and 0.925 mm. The optimized biochar size were opted for later being activated using HCl with a concentration of 3%; 9%; and 15%. The leaching process of fertilizer, aiming to imitate the rain water washing, was performed by pouring water on a daily basis on a sand column with the presence of biochar saturated with colorized fertilizer. The obtained solution were then characterized using Spectrophotometer. The results show that the estimated release time for the case with the absence of biochar is 36 days, in contrast to 55 days for the case with the presence of biochar. 
Influence of Sodium Carbonate Activator Concentration and Activated Carbon Size on The Reduction of Total Dissolved Solid (TDS) and Chemical Oxygen Demand (COD) of Water Diah Puspita Nurmalasari; Susilowati Susilowati; Avido Yuliestyan; I Gusti S. Budiaman
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2019: PROSIDING SNTKK 2019
Publisher : Seminar Nasional Teknik Kimia Kejuangan

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Abstract

Valuable Chemicals Derived from Pyrolysis Liquid Products of Spirulina platensis Residue Siti Jamilatun; Budhijanto Budhijanto; Rochmadi Rochmadi; Avido Yuliestyan; Arief Budiman
Indonesian Journal of Chemistry Vol 19, No 3 (2019)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (356.615 KB) | DOI: 10.22146/ijc.38532

Abstract

With a motto of preserving nature, the use of renewable resources for the fulfillment of human needs has been seen echoing these days. In response, microalgae, a water-living microorganism, is perceived as an interesting alternative due to its easy-to-cultivate nature. One of the microalgae, which possess the potential for being the future source of energy, food, and health, is Spirulina plantesis. Aiming to identify valuable chemicals possibly derived from it, catalytic and non-catalytic pyrolysis process of the residue of S. plantesis microalgae has been firstly carried out in a fixed-bed reactor over the various temperature of 300, 400, 500, 550 and 600 °C. The resulting vapor was condensed so that the liquid product consisting of the top product (oil phase) and the bottom product (water phase) can be separated. The composition of each product was then analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). In the oil phase yield, the increase of aliphatic and polyaromatic hydrocarbons (PAHs) and the decrease of the oxygenated have been observed along with the increase of pyrolysis temperature, which might be useful for fuel application. Interestingly, their water phase composition also presents some potential chemicals, able to be used as antioxidants, vitamins and food additives.
Equilibrium Modeling of Astaxanthin Extraction from Haematococcus pluvialis Putri Restu Dewati; Rochmadi Rochmadi; Abdul Rohman; Avido Yuliestyan; Arief Budiman
Indonesian Journal of Chemistry Vol 21, No 3 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.56965

Abstract

Astaxanthin is a natural antioxidant, and the highest content of this compound is found in Haematococcus pluvialis microalgae. Microwave-assisted extraction (MAE) is one of the environmentally friendly extraction methods and has many advantages. This study aims to investigate the extraction of astaxanthin through the MAE method using various solvents. Several equilibrium models were proposed to describe this solid-liquid equilibrium. The solid-liquid extraction equilibrium parameters were determined by minimizing the sum of squares of errors (SSE), in which equilibrium constants were needed for scaling up purposes. Previously, the microalgae were pretreated with HCl to soften their cell walls in order to improve the extraction recovery. In this study, dichloromethane, acetone, methanol, and ethanol were used as the solvents for extraction. The astaxanthin concentration was determined by high-performance liquid chromatography (HPLC) and spectrophotometry. Astaxanthin was found to attain equilibrium at 57.42% recovery in a single-step extraction. Thus, several steps were required in sequence to obtain an optimum recovery. The experimental data were fitted to three equilibrium models, namely, Henry, Freundlich, and Langmuir models. The experimental data were well fitted to all the models for the extraction in dichloromethane, methanol, ethanol and acetone, as evident from the almost same SSE value for each model.
Producing Gel With Various Ingredients: a Review Marthin Rivai Hezekiel Siagian; Sayid Umar Abraham; Avido Yuliestyan
Equilibrium Journal of Chemical Engineering Vol 8, No 1 (2024): Volume 8, No 1 July 2024
Publisher : Program studi Teknik Kimia UNS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/equilibrium.v8i1.84242

Abstract

Unhealthy fat choices in diets are linked to obesity and other health problems. The food industry faces a challenge to develop low-fat products that maintain desirable textures and functionalities. Food gels, semi-solid materials formed by small molecules or large organic molecules that can hold liquids, offer a promising approach for replacing fat in various food applications like yogurt, ice cream, and cheese. This review discusses recent research on: Types of biopolymers used for fat substitution in gels, including proteins, polysaccharides, and their combinations. The importance of rheological studies in understanding the characteristics of these fat-substituted gels. How manipulating rheological parameters can influence the texture and properties of food products.Keywords: Gel, Rheology, Fat, Protein, Polysaccharide