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All Journal VALENSI Jurnal Prajaiswara
Damayanti, Widya Anggun
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Chemistry Economics, Econometrics & Finance Education Environmental Science Social Sciences Other

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Production of Bio hydrocarbons from Vegetable Oils and Animal Fats Using Magnesium Oxide as Catalyst Siregar, Yusraini Dian Inayati; Riyadhi, Adi; Damayanti, Widya Anggun; Rizkiansyah, Rizkiansyah; Murditya, Muhammad Bagas
Jurnal Kimia Valensi Jurnal Kimia VALENSI Volume 9, No. 2, November 2023
Publisher : Syarif Hidayatullah State Islamic University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15408/jkv.v9i2.30865

Abstract

Bio hydrocarbons are renewable fuels that can be produced through the catalytic deoxygenation of fatty acids, resulting in compositions like gasoline, kerosene, and diesel fractions derived from petroleum. The objective of this study is to generate gasoline, kerosene, and diesel from vegetable oils and animal fats using an MgO catalyst synthesized through the calcination of Mg-citrate. The characterization of the MgO catalyst, employing Fourier Transform Infrared (FTIR), X-Ray Diffraction (XRD) and Brunauer-Emmett-Teller (BET) surface adsorption method, revealed the presence of crystalline MgO and showed that mesoporous MgO with average pore size of 15.52 nm and exhibiting a surface area of 35.68 m2 g-1. The MgO catalyst was utilized in the deoxygenation reaction of palm oil, palm wax, and chicken fat, leading to the production of bio hydrocarbons with paraffin and olefin compositions like those found in gasoline, kerosene, and diesel derived from petroleum. Gas Chromatography-Mass Spectroscopy (GCMS) analysis of the liquid product demonstrated that the highest quantity of gasoline was derived from palm wax, followed by palm oil and chicken fat. Palm wax exhibits promising potential as a raw material for gasoline production through the deoxygenation reaction, specifically through decarboxylation and decarbonylation processes facilitated by the MgO catalyst.
Validity Of PALACA Media On Enumeration Material For Grade 4 Elementary School Andayani, Sinta; Damayanti, Widya Anggun; Kristiyani, Leony; Taqwa, Aldino Khoirozadit; Ardianti, Sekar Dwi
Jurnal Prajaiswara Vol. 6 No. 2 (2025): Agustus 2025
Publisher : Badan Pengembangan Sumber Daya Manusia (BPSDM) Provinsi Jambi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55351/prajaiswara.v6i2.191

Abstract

Introduction/Primary Objective: This study aims to describe the validation and practicality of PALACA (Numeric Board) media as a mathematics learning aid on the material of enumerated numbers for grade IV elementary school students. Research Methods : The media was developed using the Research and Development (R&D) method with a modified Borg and Gall model. Validation was conducted by media experts, material experts, and educational practitioners to assess the feasibility of using the media in learning. Findings/Results: The validation results show that PALACA media obtained an average score of 4.8 from media experts and practitioners, as well as 4.0 from material experts, which indicates that this media is very suitable for use. The results of the teacher's practicality test of the media reached 96.6% and the students' responses amounted to 95% which showed very good acceptance from direct users. PALACA media is considered to be able to increase students' motivation and understanding of the concept of counting numbers through a concrete and interactive approach. Conclusion :  Thus, this media can be an effective alternative in learning mathematics in elementary schools. This research also contributes to the development of visual-based and participatory learning media. However, the trial was conducted on a limited scale so further research needs to be done with a larger sample to strengthen the generalization of the results.
Co-Authors Adi Riyadhi Andayani, Sinta Kristiyani, Leony Murditya, Muhammad Bagas Rizkiansyah, Rizkiansyah Sekar Dwi Ardianti Taqwa, Aldino Khoirozadit Yusraini Dian Inayati Siregar