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All Journal Eksergi: Chemical Engineering Journal Indonesian Journal of Chemistry
Putri Restu Dewati
Chemical Engineering Department, Universitas Pembangunan Nasional Veteran Yogyakarta, Jl. SWK No. 104, Yogyakarta 55283, Indonesia
Chemical Engineering, Chemistry & Bioengineering Chemistry Control & Systems Engineering Industrial & Manufacturing Engineering Materials Science & Nanotechnology

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Pre-treatment Process of Biodiesel Production From Waste Cooking Oil Putri Restu Dewati; Achmad Halim Purbohandono; Arief Budiman
Eksergi Vol 11, No 1
Publisher : Prodi Teknik Kimia, Fakultas Teknologi Industri, UPN "Veteran" Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31315/e.v11i1.318

Abstract

 Methyl ester of fatty acids known as biodiesel, synthesized from vegetable oils or animal fats, is a promising alternative fuel due to the limited resource of fossil fuel and the environment concern. There are large amount of low cost oil such as waste cooking oil that could be converted to biodiesel. However there is problem related to process of this low cost oil since they often contain large amounts of free fatty acid (FFA) that cannot be converted to biodiesel using alkalin ecatalyst. In this paper, a technique for reducing the FFA as pre-treatment in biodiesel production from waste cooking oil is studied. This pre-treatment step is aimed to esterify the FFA before trans-esterifying process of triglycerides with an alkaline-catalyst to complete the reaction. The main parameters of this process such as temperature, the molar ratio of methanol to acid catalyst, and catalyst loading were investigated to determine the optimum condition for converting of the FFA to usable esters. The result shows that the best condition for reducing of FFA was obtained at 65o C, with a molar ratio of oil to methanol of 1:6, and catalyst loading of 2 wt% H2SO4 .
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.
Co-Authors Abdul Rohman Achmad Halim Purbohandono Arief Budiman Avido Yuliestyan Rochmadi Rochmadi