Universitas Negeri Manado, Jurusan Kimia: Open Journal Systems
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Characterization of Activated Charcoal from Pyrolysis Of Human Hair Cutting and Its Utilization as an Adsorbent
Get PDFThis study aims to determine the characteristics of activated carbon from human hair cutting waste and to determine its ability to adsorb metals contained in water. This study uses an experimental method that is preceded by the activation of charcoal with KOH activator. Then continued with characterization using Fourier Transform Infra - Red (FTIR), X-Ray Diffraction (XRD), Scanning Electron Microscope Energy Dispersive X-Ray (SEM-EDS) and Atomic Absorption Spectrophotometer (AAS). The results of the study showed that the FTIR spectrum showed the presence of a groupOH, CH, C=C and CO. The results of SEM analysis of activated carbon show the morphology of the pores of unactivated carbon, namely the surface looks smooth and dense with small particles evenly distributed and there are no large pores or significant cracks. Activated carbon from activation with KOH has a surface structure that looks more porous than before activation. The results of EDS analysis show the elemental composition of unactivated carbon and after activation using KOH only the C element is produced. XRD analysis of unactivated activated carbon shows one wide and not sharp diffraction peak. This characteristic indicates that the material has an amorphous structure, which means that the atoms in the material are not arranged crystalline but randomly. The relatively low diffraction intensity and high background strengthen the amorphous character of this pyrolysis carbon. After activation using KOH, the diffraction pattern still shows a wide peak at the same 2θ, but with higher intensity and a more defined peak shape. The results of AAS analysis show that activation with KOH provides high adsorption efficiency of 26.82%
Analysis Of Nutrient Content And Organoleptic Test Of Fish Waste POC With The Addition Of Ecoenzyme
Get PDFNutrients in fish waste can cause pollution (eutrophication) when directly discharged into waters. Efforts to minimize this can be done by processing fish waste into POC. Making POC from fish waste can be done by adding ecoenzymes. The purpose of this study was to observe the organoleptic, pH and nutrient content of POC from fish waste with and without the addition of ecoenzymes. The stages of the study were ecoenzyme production, POC products, organileptic tests, pH observations, and analysis of nitrogen (N), phosphorus (P), and potassium (K) content. Based on the results of the study on the observation of organoleptic odor tests before fermentation, Bucket 1 without the addition of ecoenzyme has a slightly rotten and fishy odor, reddish brown in color, pH 6, after fermentation it has a sour and fishy odor, brown in color pH 5. Bucket 2 With the addition of ecoenzyme has a slightly rotten and fishy odor, reddish brown in color, pH 5, after fermentation it has a slightly sour and fishy odor, brown in color, pH 4. The NPK content in bucket 1 without the addition of ecoenzyme is 0.35%, 0.19%, 0.09%, in bucket 2 with the addition of ecoenzyme is 0.57%, 0.32%, 0.12%
Penerapan Media Interaktif Berbasis Game Based Learning Dengan Platform Kahoot Pada Materi Kimia Hijau Untuk Meningkatkan Hasil Belajar Siswa
Get PDFStudents need more creative and innovative media and methods to support learning activities, namely interactive media and game methods that stimulate students to be more active in learning. This research is aimed at improving student learning outcomes through the application of interactive Game Based Learning media with the Kahoot platform on green chemistry material. This research uses a classroom action research method with 4 stages used, namely planning, implementing actions, observing and reflecting; The results of implementing interactive media based on game based learning with Kahoot showed an increase in learning outcomes, the results of the final test in cycle 1 were 37.5% student completeness and in cycle II there was 87.5% student completion. In conclusion, the application of interactive media based on game based learning can improve student learning outcomes.Peserta didik membutuhkan media dan metode yang lebih kreatif dan Inovatif untuk mendukung kegiatan pembelajaran, yaitu media interaktif dan metode permainan yang merangsang siswa untuk lebih aktif dalam pembelajaran. Penelitian ini untuk ditujukan untuk peningkatan hasil belajar siswa melalui penerapan media interaktif Game Based Learning dengan platform Kahoot pada materi kimia hijau. Penelitian ini menggunakan metode penelitian tindakan kelas dengan 4 tahapan yang digunakan yaitu perencanaan, pelaksanaan tindakan, pengamatan dan refleksi; hasil dari penerapan media interaktif berbasis game based learning dengan Kahoot terjadi peningkatan hasil belajar, hasil tes akhir siklus 1 terdapat 37,5% ketuntasan siswa dan siklus II terdapat 87,5% ketuntasan siswa. Kesimpulannya penerapan media interaktif berbasis game based learning ini dapat meningkatkan hasil belajar sisw
Effect of Storage Time Duration on the Quality of Immersion Oirom Kepuh Vegetable Material (Sterculia foetida L) on Imaging of Plant Tissue of Shallot Cell
Get PDFThe dependence of optical microscopes on one of the consumables, especially at high magnification, so that the imaging results are clearly visible or not blurry, is immersion oil. In an effort to answer this need, a study has been conducted to find an alternative immersion oil by utilizing vegetable oil from the kepuh plant (Sterculia Foetida L) from Alor Regency. This study tested the quality of kepuh seed meat oil from soxhlet extraction and purified using the Deguming, Neutralization, Bleaching, Stearin, Centrifugation methods, and stored in glass bottles, wrapped in aluminum foil, and stored at room temperature (25-280C) from 2016 to 2024 (8 years). The test used three parameters, namely first; comparison of physical and chemical properties parameters, namely density, viscosity, refractive index, acid number and Aperture Value for kepuh oil data in 2016 and 2024, were recorded to have changed, but the imaging photographs still provided the same brightness as standard oil. Second; the GC-MS identification parameters showed that, even though there were 32 peaks in the kepuh oil spectrum, and the nomination of two compounds was identified, namely linoleic acid 34.58%, stearic acid 6.98%, the imaging effect was still clearly visible. Third, a comparison of the imaging results of standard immersion oil and immersion oil from kepuh for oil conditions in 2024 showed imaging results that were not significantly different
Isolation and Identification of Indigenous Polypropylene-Degrading Bacteria Isolated From Bestari Landfill of Probolinggo
Get PDFThe Bestari Landfill of Probolinggo City collects a variety of plastics waste, most of it already in a degraded state. It is estimated to be potential habitat for polypropylene-degrading bacteria. Previous NGS studies identified 2,400 species of bacteria, but did not reveal their physiological and functional characteristics. This study aims to identify PP-degrading bacteria using 16S rRNA analysis. Isolation is carried out by the Enrichment method on Mineral Salt Media (MSM) containing PP granules. The research stages included sampling, isolation, and screening of bacteria for the most effective degrading agents. Six isolates of polypropylene-degrading bacteria were discovered at the Bestari Landfill of Probolinggo City, including B1UM1, B1UM2, B1UM3, B2UM1, B2UM2, and B2UM3. After 15 days of incubation, potential isolates B1UM1, B1UM2, and B2UM1 showed the highest polymer reduction of 8.25%, 7.15%, and 6.25%. Gram staining results showed that isolate B1UM1 was coccus and a Gram-positive bacterium, while isolates B1UM2 and B2UM1 were basil and Gram-positive. Genotypic identification through 16S rRNA sequence analysis showed that isolate B1UM1 had 100.0% similarity with Staphylococcus haemolyticus, BIUM2 had a 100% similarity to Bacillus cereus, and B2UM1 had a 99% had a similarity to Bacillus sp
Ability Antioxidant and Anti-inflammatory Phycocyanin from Extract Spirulina platensis
Get PDFIncreased exposure to free radicals and chronic inflammatory processes are major factors in the development of various degenerative diseases, including cancer, diabetes, and cardiovascular disease. Therefore, the search for natural bioactive compounds with antioxidant and anti-inflammatory properties has become a major focus in pharmaceutical and biomedical research. Phycocyanin is a complex protein pigment from the microalgae Spirulina platensis which is known to have biological activities, especially as an antioxidant and anti-inflammatory. This study aims to evaluate the antioxidant and anti-inflammatory properties of phycocyanin extract obtained through maceration and freeze-thawing methods using PBS solution pH 7.4 and distilled water. Antioxidant activity was evaluated using the ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonate)) method, while the anti-inflammatory potential was tested using the protein denaturation inhibition method. The test results showed that the phycocyanin extract had quite strong antioxidant activity with an IC₅₀ value of 82.86 mg/L. In addition, anti-inflammatory activity was also shown with an IC₅₀ value of 73.92 mg/L in the protein denaturation inhibition test. These results indicate that phycocyanin extract from Spirulina platensis has the potential as a natural bioactive agent in the development of nutraceutical, cosmetic, and pharmaceutical products. Further studies are needed to understand the molecular mechanisms and in vivo testing to support its clinical application
Pengaruh Model Pembelajaran Pogil (Process Oriented Guided Inquary Learning) Terhadap Hasil Belajar Siswa Pada Materi Struktur Atom Di SMA Negeri 1 Tondano
Get PDFTujuan penelitian ini yaitu untuk Mengetahui Perbedaan hasil belajar siswa sebelum dan sesudah penggunaan Model Pembelajaran POGIL (Process Oriented Guided Inquary Learning) Pada Materi Struktur Atom Di SMA Negeri 1 Tondano. Penelitian ini dilakukan pada kelas X IPA 3 SMA Negeri 1 Tondano pada tahun ajaran 2022/2023. Sebanyak 20 siswa kelas X IPA 3 ditetapkan sebagai sampel penelitian. Data pengujian Hipotesis uji t diperoleh nilai thitung (18,5749) lebih besar dari ttabel 2,093 pada taraf signifikan α = 0,05 dengan derajat kebebasan n-1=20-1 = 19. Uji peningkatan (N-gain) diperoleh nilai 0,77 yang termasuk dalam kategori kriteria tinggi. Dengan demikian dapat disimpulkan bahwa terdapat perbedaan hasil belajar siswa sebelum dan sesudah penggunaan model pembelajaran POGIL. Terjadinya perbedaan ini diduga karena ada pengaruh penggunaan model pembelajaran POGIL. Hal ini didukung oleh uji N-Gain sebesar 0,77 yang termasuk dalam kriteria tinggi
Characterization of Clay from Merauke Regency and Its Utilization as an Adsorbent of Free Fatty Acids in the Purification of Waste Cooking Oil
Get PDFThis study investigates the characterization and application of natural clay from Merauke as an adsorbent for the purification of waste cooking oil. The clay was characterized using X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) before and after acid activation. XRD analysis revealed quartz as the dominant mineral, while acid activation caused partial dissolution of layered silicates, leading to structural modifications without affecting quartz stability. SEM images confirmed morphological changes from compact aggregates with limited pores to rougher surfaces with larger and more interconnected pores, indicating increased surface area and porosity. Adsorption experiments demonstrated that both natural and acid-activated clays reduced free fatty acids (FFA) in waste cooking oil, with the acid-activated clay consistently showing higher efficiency. Prolonged stirring times (1, 3, and 5 hours) further enhanced adsorption, though the reduction rate decreased over time as adsorption sites approached saturation. In addition to lowering FFA levels, the treatment improved the visual quality of the oil by reducing discoloration. These findings highlight that acid-activated clay from Merauke possesses promising potential as a low-cost and effective adsorbent for oil purification and broader environmental remediation applications
Zn–Catharanthus roseus and Cu–Catharanthus roseus Complexes as Green Organometallic Photosensitizers for DSSC Applications
Get PDFThe global energy crisis and climate change issues have driven the development of environmentally friendly renewable energy sources, one of which is the dye-sensitized solar cell (DSSC) utilizing natural pigment-based photosensitizers. Catharanthus roseus (tapak dara) was selected due to its abundance of secondary metabolites and its potential to be modified into Zn and Cu nanoparticles to enhance stability and efficiency. In this study, tapak dara leaf extract was obtained using ethanol through ultrasonic extraction, then synthesized into Zn and Cu nanoparticles with Zn:Cu ratios of 0:4, 1:3, 2:2, 3:1, and 4:0 via green synthesis. The resulting nanoparticles were deposited onto TiO₂ electrodes, with Pt used as the counter electrode in the DSSC. The cells were tested under 9 mW halogen light. The results revealed that the Zn:Cu ratio influenced crystallite size, morphology, and solar cell efficiency. XRD characterization confirmed the formation of ZnO and Cu phases with crystallite sizes ranging from 9 to 40 nm, while SEM analysis showed nanometer-sized particles with a tendency to agglomerate. The highest efficiency was achieved at a 3:1 ratio, reaching 120 × 10⁻⁴ %, indicating that Zn/Cu–tapak dara nanoparticles hold strong potential as effective photosensitizers
Synthesis and Physicochemical Characterization of Castor Oil Methyl Ester
Get PDFThe increasing consumption of biodiesel has led to the continued development of biodiesel production using oils that do not compete with food, for example castor oil. This study aims to synthesize and characterize castor oil methyl ester (COME) as biodiesel. The FFA of castor oil is 0.66%, so that a transesterification reaction with methanol using a KOH catalyst can be carried out. The reaction was characterized by Thin Layer Chromatography (TLC) and Gas Chromatography-Mass Spectrometry (GCMS). The highest content of COME is methyl ricinoleate at 65.481%. followed by FFA at 0.4%, a cloud point of -9°C, a pour point of -18°C, and a density at 40°C of 887.2 kg/m3 which is in accordance with SNI. Thus, COME has the potential as a biodiesel candidate