CHEMICA: Jurnal Teknik Kimia https://journal3.uad.ac.id/index.php/chemica <table width="100%" bgcolor="#f0f0f0"> <tbody> <tr> <td width="20%">Journal title</td> <td width="60%"><strong>Chemica: Jurnal Teknik Kimia</strong></td> <td rowspan="9" valign="top" width="20%"><img src="https://journal3.uad.ac.id/public/journals/6/journalThumbnail_en_US.jpg" /></td> </tr> <tr> <td width="20%">Initials</td> <td width="60%"><strong>CHEMICA</strong></td> </tr> <tr> <td width="20%">Abbreviation</td> <td width="60%"><em><strong>CJTK<br /></strong></em></td> </tr> <tr> <td width="20%">Frequency</td> <td width="60%"><strong>3 issues per year | April- August- December</strong></td> </tr> <tr> <td width="20%">DOI</td> <td width="60%"><strong>Prefix 10.26555/chemica</strong><img src="https://journal3.uad.ac.id/index.php/chemica/index" alt="" /><strong><img src="http://journal2.uad.ac.id/index.php/eltej/management/settings/context//public/site/images/dyoyo/CROSREFF_Kecil2.png" alt="" /></strong><strong><br /></strong></td> </tr> <tr> <td width="20%">ISSN</td> <td width="60%"><strong>E-ISSN: <a href="https://issn.brin.go.id/terbit/detail/1400229773" target="_blank" rel="noopener">2355-8776</a></strong></td> </tr> <tr> <td width="20%">Editor-in-chief</td> <td width="60%"><a href="https://www.scopus.com/authid/detail.uri?authorId=55939373600" target="_blank" rel="noopener"><strong>Prof. Maryudi, Ph.D.</strong></a></td> </tr> <tr> <td width="20%">Publisher</td> <td width="60%"><a href="https://uad.ac.id/en/"><strong>Universitas Ahmad Dahlan</strong></a></td> </tr> <tr> <td width="20%">Citation Analysis</td> <td width="60%"><strong><a href="https://scholar.google.co.id/citations?user=KxqSQKAAAAAJ&amp;hl=en" target="_blank" rel="noopener">Google Scholar</a> | <a href="https://sinta.kemdikbud.go.id/journals/profile/329" target="_blank" rel="noopener">Sinta</a><br /></strong></td> </tr> </tbody> </table> <hr /> <div align="justify"> <div align="justify"><strong>CHEMICA: Jurnal Teknik Kimia</strong>, p-ISSN: <a href="https://issn.brin.go.id/terbit/detail/1400228866" target="_blank" rel="noopener">2355-875X</a> | e-ISSN: <a href="https://issn.brin.go.id/terbit/detail/1400229773" target="_blank" rel="noopener">2355-8776</a>, is an international, peer-reviewed, open access, online journal that publishes manuscripts or scientific papers in Chemical Engineering published by Universitas Ahmad Dahlan in <strong>April</strong>, <strong>August</strong>, and <strong>December</strong>. In 2023, or start volume 10 number 3, Chemica: Jurnal Teknik Kimia has been accredited by Direktorat Jendral Pendidikan Tinggi Riset dan Teknologi through SK 10/C/C3/DT.05.00/2025 (<strong>Sinta 2</strong>) for the period of 2023-2028. The journal consists of high-quality technical manuscripts on advances in state-of-the-art chemical reaction engineering, separation, optimization, process control, process system engineering, waste treatment, food, and material technology. Editors will initially review submitted papers in English, followed by a minimum of two reviewers.</div> </div> en-US lab.che.uad@gmail.com (Prof. Maryudi, S.T., M.T., Ph.D.) agus.aktawan@che.uad.ac.id (Agus Aktawan) Tue, 04 Nov 2025 06:13:36 +0000 OJS 3.2.1.4 http://blogs.law.harvard.edu/tech/rss 60 Optimization Process of Oil Palm Biomass-Based Activated Carbon for Palm Oil Mill Effluent Treatment https://journal3.uad.ac.id/index.php/chemica/article/view/403 <p>The rapid expansion of the palm oil industry has significantly increased the volume of palm oil mill wastewater, creating a growing need for its effective treatment and management. Filtration is one of the unit operations involved in treating Palm Oil Mill Effluent (POME), and activated carbon is a commonly used medium in filtration systems. In this study, activated carbon was synthesized from oil palm biomass, including empty fruit bunch (EFB) and palm kernel shell (PKS). The synthesis involved a series of experiments with varying concentrations of H3PO4 (20–60% w/w), activation temperatures (70–100 C), and activation times (30–60 min). The operating conditions for activation were varied using a 23-factor complete factorial design with one center point (analyzed in the Minitab Program). Performance analysis was conducted by evaluating the ability of activated carbon to reduce pollutant parameters in POME, including biochemical oxygen demand (BOD), chemical oxygen demand (COD), and color. Activated carbon from EFB and PKS was successfully synthesized with larger pores, ranging from 10.91 um to 15.22 um, compared to raw EFB and PKS, which had pore sizes ranging from 1.52 um to 2.11 um. It was also found that activation temperature significantly affected the percentage of COD and BOD removal compared to phosphoric acid concentration and activation time. The optimum adsorbent was a 75% PKS:25% EFB mixture, activated with 20 wt% H3PO4 at 70 C for 30 min, achieving a COD removal of 64.0% along with a maximum BOD of 91.2%.</p> Yenny Sitanggang, Krissandarta Tarigan, Fauzatu Arabica Yatasya Hasibuan Copyright (c) 2025 Universitas Ahmad Dahlan https://creativecommons.org/licenses/by-sa/4.0 https://journal3.uad.ac.id/index.php/chemica/article/view/403 Wed, 05 Nov 2025 00:00:00 +0000 Recovery of Waste Engine Oil Using Vacuum Distillation: Effect of Solvent Pre-Treatment https://journal3.uad.ac.id/index.php/chemica/article/view/440 <p>The purification process of used engine oil, which involves vacuum distillation preceded by pretreatment using chemical solvents such as acetic acid and sodium hydroxide (NaOH), has been studied to improve the quality and efficiency of base oil recovery. Pretreatment was performed using varying solvent concentrations of 5%, 10%, and 15% (v/v) and incubation times of 24, 48, and 96 hours. The primary objective of pretreatment is to decompose polar contaminants and break down complex compounds, making them easier to separate during the distillation stage. The vacuum distillation process was carried out at a pressure of -70 cmHg and a temperature of 230°C, allowing separation of fractions based on differences in boiling points. Experimental results showed that the average density of the base oil distilled from motor oil was 833 kg/m³ and from car oil was 840 kg/m³, approaching the characteristics of new oil. Optimum conditions were achieved by pretreating with 15% v/v acetic acid for 48 hours, resulting in the highest base oil yield of 45.0%. However, NaOH solvent produced more precise visual results, indicating a better ability to bind polar impurities. Chemical component analysis revealed that the main compounds of the new oil, such as octanoic acid, 1,2,3-propanetriol, and glyceryl tridecanoate, were not present in the distillate because they underwent thermal degradation to alkanes and cyclic compounds. On the other hand, additives such as pentatriacontane, hexacosane, and tetrapentacontane-1,54-dibromo were still detected, proving their thermal stability.</p> Hendriyana Copyright (c) 2025 Universitas Ahmad Dahlan https://creativecommons.org/licenses/by-sa/4.0 https://journal3.uad.ac.id/index.php/chemica/article/view/440 Tue, 04 Nov 2025 00:00:00 +0000 Isolation of Bioactive Compounds from Melastoma Malabathricum (Keduruk) for Antibacterial Activity Against Staphylococcus aureus and Pseudomonas aeruginosa to Promote Wound Healing https://journal3.uad.ac.id/index.php/chemica/article/view/470 <p>Melastoma malabathricum (keduruk) is a traditional medicinal plant widely used in Southeast Asia for wound healing. However, studies on its bioactive compounds and antibacterial activity remain limited. This study aimed to isolate and identify antibacterial compounds from M. malabathricum leaves and evaluate their potential for topical wound-healing applications. Fresh leaves were extracted using 70% ethanol via maceration, followed by liquid–liquid partitioning and chromatographic purification. Phytochemical screening confirmed the presence of flavonoids, tannins, saponins, alkaloids, and terpenoids. Among the fractions, the ethyl acetate extract exhibited the strongest antibacterial activity and was subjected to further isolation and characterization using ¹H-NMR, ¹³C-NMR, and HR-TOF-MS, revealing flavonoid derivatives as the major constituents. Antibacterial activity was tested by the disk diffusion method against Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853. At 10,000 µg/mL, the ethanol extract produced inhibition zones of 15.6 ± 0.6 mm against S. aureus and 12.1 ± 0.5 mm against P. aeruginosa. The isolated flavonoid compound showed stronger inhibition—19.2 ± 0.6 mm and 16.7 ± 0.5 mm, respectively—comparable to gentamicin (22.8 ± 0.7 mm and 21.5 ± 0.6 mm). The antibacterial effect was more pronounced against Gram-positive bacteria, likely due to structural differences in the cell wall. Overall, M. malabathricum leaves, particularly the ethyl acetate fraction and its flavonoid constituents, demonstrate strong antibacterial potential and could serve as natural candidates for developing topical formulations to support wound healing.</p> Harizon Harizon, Febbry Romundza, Harlis Harlis, Mia Aina, Asmiyunda Asmiyunda Copyright (c) 2025 Universitas Ahmad Dahlan https://creativecommons.org/licenses/by-sa/4.0 https://journal3.uad.ac.id/index.php/chemica/article/view/470 Wed, 05 Nov 2025 00:00:00 +0000 Utilization of Modified Amylum from Oil Palm Trunk for The Production of Edible films as A Substitute for Primary Packaging https://journal3.uad.ac.id/index.php/chemica/article/view/409 <p>This research aims to produce edible film from non-productive Oil Palm Trunk (OPT) starch. Starch from OPT contains high amylose, so it is easier to modify. In this study, OPT starch was altered through hydrolysis with an acetate buffer solution at pH 7, followed by a bleaching stage. Meanwhile, the edible film-making process involved mixing OPT starch with various types of plasticizers, including gelatin, glycerol, CMC, and chitosan, before the molding and drying process. The best edible film was obtained from starch modified with an acetate buffer solution (20 mL) and Carboxymethyl Cellulose (CMC) plasticizer, processed at 80 °C with a mixing time of 30 minutes. Edible films with these variations had the highest tensile strength, elongation, and Young's modulus values, respectively, of 29.6342 MPa, 1.1333%, and 4.3092 MPa. The results of the solubility test indicate that the primary packaging product, when applied as an edible film for instant noodle seasoning packaging, can help mitigate environmental pollution problems. It dissolves completely in cold water and immediately dissolves when poured over hot water, along with instant noodles. However, there needs to be improvement in the elongation value so that edible film products can protect the contents of their packaging from external influences, including environmental conditions, perfectly when used. The result of this research is the first finding on the application of acetate buffer-modified OPT starch as a primary packaging material, similar to edible films currently on the market.</p> Faradila Nur Chairunnisya, Diana Pramudita, Edi Anto Saputra, Fachri Nur Hilmi, Wilanda Tasya, Aris Sandi, Lestari Hetalesi Saputri Copyright (c) 2025 Universitas Ahmad Dahlan https://creativecommons.org/licenses/by-sa/4.0 https://journal3.uad.ac.id/index.php/chemica/article/view/409 Mon, 17 Nov 2025 00:00:00 +0000 Formulation of Calcium Microcapsules from Eggshells Using Maltodextrin and Gelatin as Coating Materials for Health Supplements https://journal3.uad.ac.id/index.php/chemica/article/view/483 <p>Eggshell waste is a primary environmental concern resulting from the high consumption of chicken eggs in Indonesia. In 2023, egg consumption reached 6.69 kg/capita/year, producing an estimated 1.86 million tons of eggshell waste. This study investigates, for the first time, the combination of maltodextrin and gelatin via the thin-layer drying method for microencapsulating calcium extracted from eggshells. Eggshells contain around 98% calcium carbonate (CaCO3) and 28% elemental calcium, highlighting their potential as an alternative, low-cost, and sustainable source of natural calcium supplements. However, calcium extracted from eggshells is highly susceptible to environmental degradation, limiting its direct application. To overcome this, microencapsulation technology is applied to enhance calcium stability, solubility, and bioavailability. In this study, calcium was extracted using the Heat Assisted Extraction (HAE) method with 2N HCl at 90 C for 2 hours, then encapsulated with maltodextrin and gelatin at ratios of 1:0, 0:1, 1:1, 2:3, and 3:2. The extracted calcium concentration reached 9.041 mg/g. The best performance was achieved at a maltodextrin-to-gelatin ratio of 3:2, yielding an encapsulation efficiency of 90.33%, a solubility of 77.11%, and a favourable particle morphology. These findings not only demonstrate the potential of eggshell-derived calcium microencapsulation to reduce waste but also contribute to achieving SDG 3 (Good Health and Well-being) by providing alternative calcium sources and to SDG 12 (Responsible Consumption and Production) through waste valorization and sustainable resource utilization.</p> Maharani Kusumaningrum, Maulida Zakia, Ramavi Akbar Akhsanul Fitrah, Luthfi Rizkiyana, Chealsy Zafarina Audyaz-Zahra, Aisya Eka Indriawati, Hidayatul Munadhiroh, Berliana Putri Rahmalia, Elvina Belva Fithriyah, Anin Bimarhamah, Hasna Rifqi Nabila Copyright (c) 2025 Universitas Ahmad Dahlan https://creativecommons.org/licenses/by-sa/4.0 https://journal3.uad.ac.id/index.php/chemica/article/view/483 Mon, 17 Nov 2025 00:00:00 +0000