Garuda - Garba Rujukan Digital

Synthesis and Characterization of Biodiesel from Coconut Oil Using Renewable ZnO/CaO-CA Catalyst with Microwave Heating Surya Julius Sembiring; Lisnawaty Simatupang; Jhony Hartanta Sembiring; Elfrida Ginting
Jurnal Kimia Riset Vol. 11 No. 1 (2026): June
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkimris.v11i1.74231

Biodiesel is a type of liquid fuel produced from vegetable oil and has combustion properties similar to diesel fuel, which is processed through esterification-transesterification as an alternative to fossil fuels. This study aims to optimize the esterification-transesterification process by examining the effect of time on the conversion of coconut oil into biodiesel based on the suitability of SNI 7182-2015. The methodology used involves microwave heating. Biodiesel is synthesized using CaO catalyst derived from fish bone waste impregnated with ZnO and activated carbon support. Catalyst preparation is carried out through impregnation, followed by calcination at 500℃. The characterization of the ZnO/CaO-CA catalyst was performed using X-Ray Diffraction (XRD), Thermogravimetric Analysis (TGA), and Surface Area Analyzer (SAA) using the Brunauer-Emmett-Teller (BET) method. This was followed by an esterification-transesterification process with varying times of 4, 5, 6, 7, and 8 minutes at a power of 600 watts. The results of the ZnO/CaO-CA catalyst characterization analysis in the XRD analysis of the single CaO catalyst and the ZnO/CaO-CA catalyst at 2θ were 2θ = 32.22°, 37.98°, and 53.20°, and 2θ = 31.75°, 34.43°, and 36.24°, respectively. The TGA analysis results showed thermal stability with a midpoint at 271.82℃. The SAA analysis results using the BET method showed a surface area of 5.0919 m²/g, a pore volume of 17.6×10⁻³, and a pore diameter of 22.1270 nm. Biodiesel characterization was performed on the transesterification product at the optimal time of 5 minutes using FTIR and GCMS. FTIR analysis revealed the functional groups of methyl esters, namely the methyl group (C-H) and ester groups (C-O), (C=O). GC-MS analysis identified the optimal biodiesel components as octanoic acid (3.07%), decanoic acid (5.81%), dodecanoic acid (20.48%), methyl tetradecanoate (21.33%), and hexadecanoic acid (17.50%).

Sonochemical Synthesis of Gold Nanoparticles as A Digital Image-Based Colorimetric Probe for Aluminum Ion Detection Eduwin Saputra; Sri Juari Santosa
Jurnal Kimia Riset Vol. 11 No. 1 (2026): June
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkimris.v11i1.79796

Gold nanoparticles functionalized with ethylenediaminetetraacetic acid (EDTA-AuNPs) were successfully synthesized using a sonochemical approach. The synthesis results show a characteristic red color with a SPR peak at 524 nm. The addition of Al³⁺ ions induces a color change in EDTA-AuNPs to blue with a new absorption peak at 700 nm, indicating nanoparticle aggregation. Transmission electron microscopy data confirmed that EDTA-AuNPs particles were dispersed and aggregated after reacting with Al³⁺. Particle size analysis (PSA) confirmed an increase in particle diameter from 27 nm to 161 nm after the addition of Al³⁺. The colorimetric sensor exhibited high selectivity toward Al³⁺ ions. The quantitative analysis was conducted using both UV-Visible spectrophotometry and colorimeter methods. The UV-Visible spectrophotometer method has a detection limit of 0.15 mM, while the colorimeter shows a sensitivity of 0.07 mM. The integration of digital image-based colorimeter methods enables the development of a portable, sensitive, low-cost, and simple platform for on-site detection of Al³⁺ ions.

Synthesis and Characterization of Chitosan/PVA Composite Membranes with ZnO:Al for Adsorption-Photocatalysis of Methylene Blue Dye Khabibi Khabibi; Trisna Bungah Alifa Rahman Singgong; Desita Putri Anggarini; Nor Basid Adiwibawa Prasetya; Retno Ariadi Lusiana
Jurnal Kimia Riset Vol. 11 No. 1 (2026): June
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkimris.v11i1.80508

This study explored the synthesis of chitosan/PVA membranes modified with aluminium-doped ZnO (ZnO:Al) as the adsorption-photocatalysis of methylene blue (MB). The ZnO:Al nanocomposites were synthesized by the sol-gel method and then combined with chitosan to form membranes via the phase-inversion method. The nanocomposite was characterized using UV-Vis DRS, XRD, and FTIR. In contrast, the membrane was characterized by FTIR, SEM-EDX and tested for physical properties, including weight, thickness, swelling, water uptake, porosity, and hydrophilicity. The UV-Vis DRS results showed that the band gap of ZnO:Al was 2.93 eV, while the XRD results showed a shift in the diffraction peak at an angle of 2θ = 31.722°, 34.425°, and 36.233°, with a crystallite size of 14.8 nm. The FTIR spectrum of the membrane showed a shift in the band from 2876 cm⁻¹ to 2866 cm⁻¹ and the appearance of a peak at 463 cm⁻¹, indicating the presence of Zn–O groups. SEM analysis showed that the membrane surface was rougher than the membrane without filler, and EDX confirmed the presence of Zn, O, and Al. Adsorption-photocatalysis testing of the MB showed that the chitosan/PVA/ZnO:Al 1 membrane (composed of a gram ratio of chitosan/PVA/ZnO:Al of 1.5, 1.5, and 0.15 g, respectively) provided the highest degradation efficiency of 93.07%. These results indicate that the membrane has high potential for dye-based wastewater treatment applications.

Green Synthesis of Silver Nanoparticles Using Pineapple Peel Extract as Bioreductant for Latent Fingerprint Visualization Muhammad Rafif; Aldi Tobing; Tery Mardasela; Stefany Therisia; Riyan; Rosiana Pitri; Masriani Masriani
Jurnal Kimia Riset Vol. 11 No. 1 (2026): June
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkimris.v11i1.80715

This study aimed to identify the optimal conditions for synthesizing silver nanoparticles from pineapple peel (AC-AgNPs), characterize their physicochemical properties, and assess their efficacy as latent fingerprint detectors. The synthesis process involved varying the pH, extract concentration, AgNO₃ concentration, and heating duration. Characterization was conducted using UV-Vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, scanning electronic microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX), particle size analysis (PSA), and zeta potential analyses. Optimal conditions were established at pH 11, 0.08% extract concentration, 1 mM AgNO₃, and heating for 60 min. The synthesis of AgNPs was verified using UV–visible spectroscopy at a wavelength of 400-450 nm, as evidenced by a color change attributable to surface plasmon resonance. FTIR analysis revealed the involvement of –OH and C=O groups in the reduction and capping processes, while SEM-EDX results indicated slightly agglomerated particles with a silver content of 4.91% and an evenly dispersed particle morphology on the sample surface. PSA analysis determined an average particle size of 59.5 nm, and the Zeta Potential was -16.4 mV. The AC-AgNP powder effectively visualized latent fingerprints with clear and high-contrast ridge patterns on glass and paper surfaces without compromising the ridge structures. These findings suggest that AC-AgNPs have the potential to serve as environmentally friendly latent fingerprint detectors, in accordance with the principles of green chemistry.

Green Synthesis of ZnO Nanoparticles Using Kalamansi Peel Extract (Citrus Microcarpa Bunge) for Photocatalytic Degradation of Methyl Orange Evi Maryanti; Eka Angasa; Mega Elfia; Wulan Aprilia Syafitri; Niken Parnia Norda; Eduwin Saputra
Jurnal Kimia Riset Vol. 11 No. 1 (2026): June
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkimris.v11i1.82360

This study reports the green synthesis of zinc oxide (ZnO) nanoparticles using kalamansi peel extract (Citrus microcarpa Bunge) as a natural reducing and stabilizing agent, followed by evaluation of their photocatalytic activity toward methyl orange degradation under sunlight irradiation. The synthesis was carried out via a precipitation method using extract concentrations of 2%, 4%, and 6% (w/v) to investigate the effect of bioactive compound content on the structural and photocatalytic properties of ZnO. Higher extract concentrations were expected to provide more phytochemical compounds, which could improve crystal growth control and particle stabilization during synthesis. Characterization by FTIR confirmed the presence of Zn-O and Zn-OH vibrations at 882 cm-¹. XRD analysis revealed diffraction patterns corresponding to the hexagonal wurtzite ZnO phase, with crystallinity increasing from 84.62% to 91.08% as extract concentration increased. SEM observations showed that ZnO synthesized with 2% extract experienced significant agglomeration, while 4% and 6% extract concentrations promoted the formation of irregular tube-like and nanorod morphologies with better particle distribution. EDS analysis verified the presence of Zn and O elements in all samples. Photocatalytic tests demonstrated that ZnO synthesized using 6% extract exhibited the highest degradation efficiency of methyl orange (67.8% after 120 min), which was attributed to its higher crystallinity, reduced agglomeration, and improved nanorod morphology that enhanced light absorption and reactive species generation. These results indicate that extract concentration plays a crucial role in determining the physicochemical properties and photocatalytic performance of green-synthesized ZnO nanoparticles.

Computational Docking and Dynamics Evaluation of Bioactive Compounds from Pandanus tectorius (NTT) Identified by GC-MS and LC-MS/MS as α-Glucosidase Inhibitors Andri Prasetiyo; Triviana Maruli Simanjuntak; Masditya Kresna Andinata; Resky Putri Purwitaningsih; Annisa Nurfitriany Syarifuddin; Esti Mumpuni; Partomuan Simanjuntak; Rahmatul Qodriah; Zainur Rahman Hakim
Jurnal Kimia Riset Vol. 11 No. 1 (2026): June
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkimris.v11i1.88249

Diabetes mellitus is a chronic metabolic disorder with a continuously increasing prevalence and a high risk of causing various serious complications. Inhibition of the α-glucosidase enzyme is one of the therapeutic approaches used to control postprandial hyperglycemia. however, the side effects and limitations of currently available drugs have encouraged the search for safer natural alternatives. Pandanus tectorius (screw pine) is a medicinal plant traditionally used by communities in East Nusa Tenggara (NTT), Indonesia, to reduce blood glucose levels. This study aimed to identify the bioactive compounds present in the roots and leaves of P. tectorius collected from NTT and to evaluate their potential as α-glucosidase inhibitors. Compound identification was performed using GC–MS and LC–MS/MS analyses, followed by molecular docking, ADMET and Lipinski’s rule of five predictions, and 100 ns molecular dynamics simulations. A total of 13 secondary metabolites were identified, comprising seven compounds detected by GC–MS and six compounds identified by LC–MS/MS. Molecular docking results revealed that apiin exhibited the most favorable rerank score (−119.480 kcal/mol), outperforming the reference inhibitor acarbose (−108.186 kcal/mol). Molecular dynamics analysis demonstrated that cirsimarin displayed the most balanced stability profile based on RMSD, RMSF, and binding energy parameters, whereas chrysosplin exhibited the most favorable binding energy but lower conformational stability. Overall, apiin, cirsimarin, and chrysosplin show promising potential for further development as natural α-glucosidase inhibitor candidates for the treatment of diabetes mellitus.

Enhanced Methane Adsorption Using Zeolite-A Derived from Coal Bottom Ash Supported with Activated Pineapple Leaf Fiber Randy Yusuf Kurniawan; Dwi Miftha Kurnia; Martasari Beti Pangestuti; Efraim Eleizer Manurung; Taufik Qodar Romadiansyah
Jurnal Kimia Riset Vol. 11 No. 1 (2026): June
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkimris.v11i1.89578

The present work evaluates the influence of mineral purification and zeolite formation from coal bottom ash (ZAB) on methane adsorption behavior, including the effect of incorporating KOH-treated pineapple leaf fibers as a supporting matrix (ZAB-X). ZAB was synthesized hydrothermally from Si and Al extracts from bottom ash through a smelting process at 650°C. Meanwhile, in the ZAB-X sample, pineapple leaf fibers were first activated by soaking in a 4 M KOH solution for 20 hours before being added to the zeolite slurry. Coal bottom ash was characterized using XRF and XRD to determine mineral content and phase, ICP-AES to determine the concentration of Si and Al extracts from the smelting results, while ZAB and ZAB-X solids were characterized using XRD and SEM to analyze morphology. The results of methane gas adsorption capacity under ambient conditions, specifically at 29 °C and under the applied pressure conditions, showed that ZAB-X had the highest capacity value of 7.75% by weight, followed by ZAB, BA after Fe and Ca Treatment, and BA, which were 4.69%, 2.34%, and 1.33%. The enhanced adsorption performance of ZAB-X was attributed to the formation of well-distributed zeolite crystals on the activated fiber surface, reduced particle agglomeration, and improved pore accessibility, which collectively promoted stronger methane confinement within the adsorbent structure. The obtained results indicate that aluminosilicate materials derived from industrial waste possess promising potential for sustainable methane capture applications.

Synthesis and Characterization of TiO2-Ni/ Coconut Coir Fiber for Photocatalysis of Methylene Blue Degradation Under Visible Light Bella Anggreiny; Adhitiyawarman Adhitiyawarman; Anthoni Aritonang
Jurnal Kimia Riset Vol. 11 No. 1 (2026): June
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkimris.v11i1.89741

The Ni²⁺-cation modified TiO₂ photocatalyst has been synthesized using the sol-gel method. Doping with metal ions into the TiO₂ lattice structure was carried out as an effort to reduce the band gap energy and shift the absorption region into the visible light range. The synthesized TiO₂-Ni photocatalyst was subsequently combined with coconut coir fibers as a floating material, commonly referred to as the floating photocatalyst method. This research aims to determine the effect of varying Ni dopant concentrations in TiO₂-Ni/coconut coir fibers on the percentage degradation of methylene blue. Based on XRD characterization, TiO₂-Ni with 1% dopant concentration produced crystals with a size of 8.48 nm and a crystallinity degree of 72.27%. UV-Vis DRS characterization showed that the smallest band gap energy was obtained from the TiO₂-Ni sample with 1% dopant concentration, namely 2.67 eV with an absorption wavelength of 464 nm. FTIR characterization of TiO₂-Ni/coconut coir fiber revealed the appearance of new peaks at wavenumbers 1402 cm⁻¹, 1877 cm⁻¹, and 2814 cm⁻¹, corresponding to –O– groups, ester groups, and –CH₂ groups. Photocatalytic activity tests showed that the higher the Ni dopant concentration, the lower the percentage degradation of methylene blue. The TiO₂-Ni/coconut coir fiber photocatalyst with 1% dopant concentration exhibited the highest degradation efficiency, with a decrease in absorbance of 73.09% after 120 minutes under visible light irradiation.

NH2-Functionalized Graphene Quantum Dots for Hg2+ Detection: A DFT/TD-DFT Study of Fluorescence Quenching Mechanism Berlian Sitorus; Dian Pratiwi; Ihsanul Arief
Jurnal Kimia Riset Vol. 11 No. 1 (2026): June
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkimris.v11i1.89817

Graphene Quantum Dots (GQDs) are promising nanocarbon materials for fluorescence sensing applications; however, pristine GQDs generally exhibit limited selectivity toward specific metal ions, thus requiring functional modification. This study employs Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT) computational approaches to investigate the effect of amine (–NH2) functionalization on the electronic and optical properties of GQDs and their potential application for mercury ion (Hg2+) detection. The –NH2 groups were introduced at four different edge carbon positions to evaluate the influence of substitution sites on structural stability, electronic properties, and optical response of GQDs. The results indicate that –NH₂ functionalization increases the HOMO energy level and reduces the band gap, with variations determined by the substitution position, resulting in shifts in the absorption and fluorescence spectra. Interaction with Hg2+ ions induce notable changes in the frontier molecular orbitals and may promote fluorescence quenching through a non-radiative charge transfer mechanism. Overall, these findings suggest that NH₂-functionalized GQDs possess promising characteristics for potential turn-off fluorescent sensing applications and provide theoretical insights for the rational design of nanocarbon-based sensors.

Preliminary Assessment of Ozone-Activated Chitosan as An Efficient Adsorbent for Dye Removal Nadya Alfa Cahaya Imani; Ria Wulansarie; Indrasukma Permanadewi; Maharani Kusumaningrum; Khodijah Muti'ah; Ira Listyaningrum; Fathin Latifah; Fenia Nur Azzahra
Jurnal Kimia Riset Vol. 11 No. 1 (2026): June
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkimris.v11i1.91204

Chitosan-based adsorbents are promising for wastewater treatment due to their biodegradability and abundant functional groups, but their dense structure and low porosity often limit adsorption performance. This study investigated ozone-assisted modification as a green approach to enhance the surface morphology and adsorption capacity of chitosan films under different pH (6–8), temperatures (30–50°C), and ozonation times (10–30 min). Structural characterization using SEM, optical microscopy, and FTIR showed that ozonation transformed the compact chitosan matrix into a more porous structure. However, excessive ozonation caused structural degradation and fragmentation. FTIR analysis confirmed changes in hydrogen bonding and partial modification of glycosidic linkages without destroying the main chitosan backbone. Adsorption tests using methylene blue (MB) and methyl orange (MO) demonstrated improved dye removal after ozonation, with sample 651 achieving the highest efficiencies of 47.06% for MB and 61.02% for MO. Acidic ozonation conditions produced the best performance, while prolonged treatment reduced adsorption due to excessive depolymerization and loss of active sites. Overall, controlled ozonation effectively improved the physicochemical properties and adsorption potential of chitosan for the treatment of dye-contaminated wastewater.

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kota surabaya,

Jawa timur

INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name -

Contact Email -

Phone -

Journal Mail Official -

Editorial Address -

Location Kota surabaya, Jawa timur INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kota surabaya,

Jawa timur

INDONESIA