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Teguh Endah Saraswati
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ALCHEMY Jurnal Penelitian Kimia
Published by Universitas Sebelas Maret
ISSN : 14124092     EISSN : 24434183     DOI : -
Core Subject : Science, Social, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry Energy Environmental Science Materials Science & Nanotechnology
ALCHEMY Jurnal Penelitian Kimia is a chemistry journal published by Sebelas Maret University, Surakarta. ALCHEMY Jurnal Penelitian Kimia publishes original research articles or review articles in organic chemistry, inorganic chemistry, analytical chemistry, physical chemistry, biochemistry, and environmental chemistry.
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Articles 306 Documents
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Improved Physico-Mechanical Properties and Microstructure of Modified Kenaf Fiber Reinforced Composites Eka Marya Mistar; Muhammad Muhammad
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 1 (2025): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.1.92620.64-71

Abstract

This study examined the properties of chemically modified kenaf fiber using propionic anhydride as reinforcement in vinyl ester composites. The composites reinforced by unmodified and modified kenaf fibers were fabricated using 10, 20, 30, 40, and 50% (w/w) via a hand lay-up technique. This study’s characterization included water absorption, thickness swelling, tensile and flexural strengths, and morphological analyses. The optimum physical, mechanical, and morphological properties were observed from the composite with 40% modified kenaf fiber. The optimized composite showed a considerable enhancement in the water absorption, tensile strength, and flexural strength of 1.82%, 54.90 MPa, and 55.85 MPa, respectively. These findings were supported by the fracture morphology after the mechanical test, exhibiting an enhanced interfacial modified kenaf fiber-matrix bonding. The improved characteristics of the composite were ascribed to the impact of the modification process within the fiber-matrix structures. Modified kenaf fiber via propionylation can be applied as a reinforcement material in the vinyl ester matrix.
Studi Pembuatan Bioplastik dari Pati Tapioka dengan Pektin Kulit Buah Naga (Hylocereus polyrhizus) dan Karagenan Baiq Ayu Aprilia Mustariani; Sulistiyana Sulistiyana; Putri Riska Fauziah; Miftahur Roifah
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 1 (2025): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.1.94003.121-129

Abstract

Penelitian ini bertujuan untuk membuat bioplastik berbasis pati tapioka dengan penambahan pektin dari limbah kulit buah naga (Hylocereus polyrhizus) dan karagenan. Penambahan kedua bahan tersebut untuk meningkatkan sifat fisika dan kimia bioplastik, termasuk ketebalan, opasitas, dan densitas. Uji ketebalan menunjukkan variasi antara 0,076 hingga 0,097 mm, dengan formulasi F2 yaitu bioplastik dengan variasi perbandingan karagenan 0,7 g dan pektin kulit buah naga 0,3 g memiliki ketebalan tertinggi. Pengujian opasitas memperlihatkan bahwa penambahan pektin cenderung meningkatkan opasitas, sementara karagenan menurunkannya. Nilai opasitas berkisar antara 3,020 hingga 5,976 mm⁻¹, dengan F0 memiliki nilai tertinggi. Densitas bioplastik berkisar antara 1,345 hingga 1,897 g/cm³, di mana formulasi F2 juga menunjukkan densitas tertinggi. Perolehan analisis statistik dari pengujian ANOVA bersamaan dengan Kruskal-Wallis menunjukkan bahwa penambahan pektin dan karagenan memiliki pengaruh signifikan (p < 0,05) terhadap ketiga parameter tersebut. Penelitian ini menampakkan bahwa kombinasi pektin dan karagenan efektif dalam memperbaiki sifat fisik dan optik bioplastik, menjadikannya kandidat yang potensial untuk aplikasi kemasan berkelanjutan.Study on the Production of Bioplastic from Tapioca Starch with Dragon Fruit Peel Pectin (Hylocereus polyrhizus) and Carrageenan. This study aims to synthesize tapioca starch-based bioplastics by adding pectin from dragon fruit (Hylocereus polyrhizus), peel waste, and carrageenan. Adding both materials to improve bioplastics' physical and chemical properties, including thickness, opacity, and density. The thickness test showed a variation between 0.076 to 0.097 mm, with formulation F2 namely bioplastic with a variation in the ratio of carrageenan 0.7 g and dragon fruit skin pectin 0.3 g having the highest thickness. The opacity test showed that adding pectin tended to increase opacity, while carrageenan decreased it. The opacity values ranged from 3.020 to 5.976 mm⁻¹, with F0 having the highest value. The density of bioplastics ranged from 1.345 to 1.897 g/cm³, where formulation F2 also showed the highest density. The statistical analysis results using the ANOVA and Kruskal-Wallis tests showed that adding pectin and carrageenan significantly (p < 0.05) affected the three parameters. This study shows that the combination of pectin and carrageenan effectively improves the physical and optical properties of bioplastics, making them potential candidates for sustainable packaging applications.
The Synergistic Enhancement of Electromagnetic Interference Shielding Polymer Composites using Carbon Nanofiber-Metal Oxide Hybrid Fillers Dini Deviana Saputri; Teguh Endah Saraswati; Wijang Wisnu Raharjo
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 2 (2025): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.2.97322.224-240

Abstract

In this modern era, humans cannot be separated from utilizing electronic devices. The unwanted noise or disturbance problem in electronic devices is majorly caused by Electromagnetic Interference (EMI). Recent technology and materials are being developed to manufacture EMI shielding composites. Carbon nanomaterial-based composites have become a very attractive material because of their lightweight, incredible mechanical, thermal, and conductivity properties. Carbon nanofibers (CNFs) and metal oxides are promising combination materials that reveal unique properties of both components to enhance shielding effectiveness. This combination of CNFs and metal oxides results in a synergistic effect, where the conductive CNFs enhances the reflection of EMI, and the metal oxides contribute to the absorption and attenuation of the waves. In this review article, the authors focus on the extensive discussion about the synthesis method of producing CNFs, some studies that combine CNFs and metal oxide, and some reports about using CNFs-metal oxide as a hybrid filler in the EMI shielding composites.
Solvent and Heating Duration Effects on the Formation of Local Pyrophyllite PEG-4000 Hybrid Materials Siti Mutrofin; Wanda Ainun Shabiya; Hanisah Kamilah
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 2 (2025): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.2.104456.346-357

Abstract

Hybrid materials are new materials formed by combining two or more components to produce enhanced and distinct properties from the individual constituents. One example is the hybrid system of  pyrophyllite and PEG 4000. This hybrid has not been reported and has potential for various applications. Local (Sumbermanjing) pyrophyllite-PEG 4000 hybrid was synthesized using casting and sol-gel methods with variations in solvent type (demineralized water, methanol, acetone) and heating time (1, 1.5, 2 hours) at a temperature of 100 – 105 ℃. Acetone produced the highest yield (34.89%) due to superior solvent-material interactions, while two-hour heating achieved maximum yield (36.20%) through enhanced intermolecular bonding. Statistical analysis confirmed significant differences in solvent variations, while heating time showed no significant effect. FTIR characterization revealed specific functional groups O–H stretching (Al-–OH linkage) at 3673.92 cm⁻¹, O–H stretching (3487.09 cm⁻¹), C–O stretching (1103.89 cm⁻¹), and Al–-OH bending vibration at 841.46 cm⁻¹, thus confirming successful hybrid formation. Melting point analysis showed 128.13 °C (1 hour heating hour) and 124.83 °C (2 hours heating time), indicating new material formation. 
Optimizing Heavy Metal Reduction in Chemical Industry Waste: A Comprehensive Response Surface Methodology Approach for Enhanced Environmental Sustainability Maria Peratenta Sembiring; Desi Heltina; Chairul Chairul; Sri Rejeki Muria; Melisa Phebeyola Estheria Tarigan
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 2 (2025): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.2.98970.296-304

Abstract

This study investigates the optimization of heavy metal reduction in solid waste from the chemical industry using Response Surface Methodology (RSM). The Box-Behnken design was employed to optimize the extraction parameters for removing Co, Cu, Pb, and Cr using NaCl as a solvent with Ethylenediaminetetraacetic acid (EDTA) as a chelating agent. The effects of EDTA:Fly Ash ratio, mixing duration, and extraction temperature were evaluated using induced coupled plasma (ICP) and Scanning Electron Microscope and Energy-Dispersive X-ray (SEM/EDS) analysis. NaCl proved effective in reducing Co, Cr, and Pb levels. Optimal conditions for NaCl treatment were identified as an EDTA:Fly Ash ratio of 2:1, 3 hours of mixing time, and an extraction temperature of 52.3 ℃, resulting in a 92.3% total metal reduction. ANOVA results confirmed the statistical significance of the model, with high R² values (0.932 – 0.991) for all metals. The EDTA:Fly Ash ratio and its interaction with mixing duration were found to be the most influential factors in the process. The study demonstrates the effectiveness of RSM in optimizing heavy metal reduction processes and provides insights for improving waste management practices in the chemical industry. The findings highlight the importance of process parameter optimization in enhancing the efficiency of heavy metal removal from industrial solid waste.
Valorization of Chicken Feather Keratin as an Eco-Friendly Coagulant for Ochre Dye Removal: A Sustainable Approach Sri Wahyu Murni; Tutik Muji Setyoningrum; Alim Nurjanah; Sandika Perdana Putra
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 2 (2025): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.2.96879.315-325

Abstract

This study examines the extraction of keratin from chicken feather waste and its potential use as a coagulant in ochre dye solution treatment. The extraction procedure was investigated for the effect of some parameters, such as temperature (60 – 80 °C), sodium hydroxide concentration (1 – 2 N), and extraction duration (30 – 120 minutes). The maximum keratin yield of 85.64% was obtained using 1.75 N NaOH at 70 °C for 90 minutes. Fourier Transform Infrared spectroscopy confirmed the presence of characteristic protein functional groups in the extracted keratin. Keratin showed modest efficiency as a coagulant in treating the ochre dye solution, with a maximum total solid removal of 47.13% when using a 0.4% keratin dosage-coagulant, pH 10, and 180 minutes of settling time. The study shows that chicken feather waste can be valorized while addressing environmental issues. Nevertheless, additional modification of keratin extraction is required to increase coagulation efficiency, such as considering pH conditions and using an appropriate solvent to minimize keratin degradation.
The Effect of Maltose-Sucrose Weight Ratio in Lozenges of Bajakah Root Ethanolic Extract (Spatholobus littoralis Hassk.) on Their Flavonoid Total Release, Physical, and Sensory Properties Dian Eka Ermawati; Chaterine Turu' Padang; Sholichah Rohmani; Anif Nur Artanti
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 2 (2025): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.2.95035.241-250

Abstract

Bajakah root ethanol extracts contain flavonoids, phenolics, and tannins as antioxidants that can inhibit tumor growth. However, consuming the pure extract as a supplement has an unpleasant odor and taste. Providing the extract as lozenges may give better taste, control the release of active substances, be absorbed in the oral mucosa, and avoid first-pass metabolism. Sucrose and corn syrup are the main components of lozenge fillers. This study evaluates the combination of maltose-sucrose on physicochemical properties, drug release, and taste acceptance. Bajakah roots were macerated in 50% ethanol (1:5 w/v) for three days, and the filtrate was evaporated. The extract contained 2.18% and 9.03% of flavonoids and tannins, respectively. The high proportion of sucrose increased hardness, sweet taste, pungent aroma, and better release of active substances, but did not affect the disintegration time. The maltose-sucrose weight ratio of 1:1 was selected because it met the requirements for lozenges based on the Indonesian Pharmacopoeia Edition VI, having characteristics of a weight of 250 ± 9.93 mg; hardness of 9.30 ± 2.08 kg; dissolution time of 10.48 ± 4.26 minutes; and released 80% of active substances for 60 minutes. In addition, this formula is stable in storage and is most preferred by respondents.
Optimization of Anthocyanin Extraction Process in Pacar Air (Impatiens balsamina) Flower from Canang Sari Flower Waste Audina Setya Fitriana; Edia Rahayuningsih; Rochim Bakti Cahyono
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 2 (2025): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.2.95821.401-413

Abstract

Canang sari is one of the offerings used in Hindu worship in Bali, consisting of various types of flowers, one of which is Impatiens balsamina Currently, the waste of canang sari flowers has not been utilized optimally. Pacar air (Impatiens balsamina) flower waste contains anthocyanin compounds and gives a purplish red color, which is promising as a natural dye raw material. This research aims to conduct phytochemical tests and determine the optimum operating conditions for extracting natural dyes from Pacar air (I. balsamina) flowers obtained from canang sari. The extraction of I. balsamina flowers uses acetone and ethanol solvents. Phytochemical, gravimetric, and UV-VIS spectrophotometric tests were conducted to determine the chemical content and stability. The extraction process is optimized using the Response Surface Methodology with Central Composite Design (CCD) type. The independent variables in this extraction process are: pH 1 – 4, temperature 40 – 70 ℃, and extraction time 5 – 60 minutes, while the dependent or response variable is anthocyanin content. The control variables of this extraction process are the ratio of materials and solvents of 0.0625 g/mL, and the stirring speed of 300 rpm. As a result, the optimum operating conditions of the extraction process are pH 2.84, temperature 63.85 ℃, and time 16.15 minutes, with anthocyanin levels of 18.05 mg/L.
Functional Bioplastic Based on Chitosan/Sago Starch (Metroxylon sago) with the Addition of Black Fruit (Haplolobus sp.) Leaves Ethanolic Extract Agnes Dyah Novitasari Lestari; Muchammad Fauzan Kuri Pasai; Evelina Somar; Dewi Eviane; Gabriella Shine De Kweldju
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 2 (2025): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.2.100395.337-345

Abstract

Bioplastic as an antioxidant and antibacterial packaging has been synthesized from chitosan and sago starch with Black fruit leaves ethanolic extract. The bioplastic synthesis was done by mixing a solution of chitosan, sago starch, glycerol, and ethanolic extract of Black fruit leaves, pouring it into a petri dish, and then drying it in an oven. The bioplastic produced was then characterized using Fourier transform infrared spectroscopy (FTIR). The results show that increasing the weight ratio of chitosan/sago starch increased tensile strength, decreased elongation, decreased thickness, and increased biodegradation time. The addition of ethanolic extract of black fruit leaves reduces tensile strength at a chitosan/starch weight ratio of 4:1, increases tensile strength at a chitosan/starch weight ratio of 1:1, tends to minimize elongation at both Chitosan/starch ratios, tends to increase thickness at a chitosan/starch weight ratio of 4:1, decreases thickness at a Chitosan/starch weight ratio of 1:1, and increases biodegradation time. The best bioplastic formulation in this study found in  CS11E1 (weight ratio of Chitosan/starch 1:1, extract concentration 1%), with a tensile strength of 4.71 MPa, elongation of 29.33%, thickness of 0.07 mm, and biodegradation time of 6 days.
Pengembangan Sensor Kimia Berbasis Kertas untuk Penentuan Kadar Flavonoid Total Ekstrak Daun Jambu Biji Mochammad Amrun Hidayat; Husnatul Ayniah; Indah Yulia Ningsih; Tanfidz Alishlah; Bambang Kuswandi
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 2 (2025): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.2.97150.277-283

Abstract

Sensor kimia berbasis kertas adalah piranti analisis yang menggunakan membran berpori berupa kertas untuk imobilisasi reagen kimia dan deteksi analit pada sampel volume kecil (μL – nL). Sensor kimia flavonoid total dikembangkan dengan cara melakukan ko-imobilisasi larutan aluminium klorida (AlCl3), natrium nitrit (NaNO2), dan natrium hidroksida (NaOH) pada kertas menggunakan teknik adsorpsi. Penambahan larutan kuersetin dapat mengubah warna sensor dari putih menjadi kuning yang kemudian dapat ditangkap dan dikuantifikasi dengan program ImageJ, yang dikenal sebagai teknik skanometri. Karakterisasi analitik seperti linearitas, Limit of Detection (LOD), Limit of Quantification (LOQ), presisi dan akurasi sensor dilakukan dengan menggunakan standar kuersetin. Hasil penentuan kadar flavonoid total sampel daun jambu biji menggunakan metode sensor kimia-skanometri menunjukkan kesesuaian dengan metode spektrofotometri, sehingga memiliki potensi sebagai metode alternatif untuk penentuan kadar flavonoid total.Development of Paper-Based Chemical Sensor for Determining The Total Flavonoid Content in Guava Leaf Extract. Paper-based chemical sensors are analytical devices that utilize porous paper membranes for reagent immobilization and analyte detection in small sample volumes (μL – nL). The total flavonoid chemical sensor was developed by co-immobilizing aluminum chloride (AlCl3), sodium nitrite (NaNO2), and sodium hydroxide (NaOH) solutions onto paper by using the adsorption technique. The introduction of a quercetin solution changed the sensor's color from white to yellow, which subsequently can be captured and quantified using the ImageJ program, known as the scanometric technique. The sensor's analytical characteristics, such as linearity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy, were evaluated using a quercetin standard. The results of determining the total flavonoid content of guava leaf samples using the chemical sensor-scanometric method showed agreement with the spectrophotometric method, indicating its potential as an alternative method for determining total flavonoid content.

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