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Membrane Electrode Assembly Based on Sulfonated Polysulfone-Activated Zeolite Composite Membrane for Fuel Cell Applications Armi Wulanawati; Sri Mulijani; Yoki Yulizar
Jurnal Kimia Sains dan Aplikasi Vol 29, No 1 (2026): Volume 29 Issue 1 Year 2026
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jksa.29.1.39-45

Abstract

The depletion of fuel cell reserves shows the need for alternative energy sources. In this context, fuel cells provide a promising solution, generating power without emissions. The membrane electrode assembly (MEA) in fuel cells is a critical component to maximize combustion efficiency. Therefore, this study aims to develop MEA using a composite membrane based on sulfonated polysulfone-activated zeolite (PSfs-Z). The membrane was obtained by first sulfonating polysulfone (PSf) and then adding activated zeolite. Optimum fuel performance was achieved with the activated zeolite using 3 N HCl. Sulfonation was completed, as demonstrated by a sulfonation degree of 32.63%. The absorption bands of the SO2 group vibration from SO3H of PSfs were identified at a wave number of 1111.00 and 1259.33 cm−1. The successful formation of MEA was confirmed by its morphology, as observed using a scanning electron microscope, with the formation of a catalyst layer and a membrane in the cross-section. The highest proton conductivity and cell potential obtained for PSfs-Z 3 N MEA were 0.01727 S.cm−1 and 330 mV, respectively. This means the membrane electrode assembly based on a sulfonated polysulfone-activated zeolite composite membrane has a higher potential than the
TiO2/ZnO/CuO/HDTMA-Br Composite for Photodegradation of Oxidative Compounds of Used Cooking Oil (UCO): Photodegradation of Free Fatty Acids and Peroxides Adinda Pitaloka; Komar Sutriah; Sri Mulijani; Mohammad Khotib
Bulletin of Chemical Reaction Engineering & Catalysis 2026: BCREC Volume 21 Issue 2 Year 2026 (August 2026)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.20554

Abstract

Used cooking oil (UCO) contains peroxide and FFA, which can impede UCO processing and lower the quality of downstream products. The majority of pretreatment techniques currently in use have drawbacks, such as excessive chemical use. An alternative that is more successful and efficient is photocatalysis. No research has been conducted on the photodegradation of UCO using TiO2/ZnO/CuO/HDTMA-Br composites. Precipitation was used to create the composite. The TiO2/ZnO/CuO composite has a high crystallinity, specifically 74.54% in the 1 CMC-modified catalyst, according to the characterization results. The spectrum of the synthesized TiO2/ZnO/CuO composite showed the presence of H2O and CO2 groups in addition to the primary groups of TiO2, ZnO, and CuO. Additionally, the 1 CMC modification increased pore volume and surface area. The surfactant-modified composite exhibited a more consistent morphology, as observed by SEM analysis. The best results from photocatalytic testing at different temperatures, times, and surfactant concentrations were obtained at 120 °C for an hour with a surfactant concentration of 1 CMC. These results show that degradation using TiO2/ZnO/CuO photocatalysts can lower the FFA and peroxide contents of UCO by 65% and 59%, respectively, under ideal conditions. This study focuses on FFA and peroxide value parameters as a preliminary investigation into alternative UCO pretreatment solutions. Copyright © 2026 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Facile Synthesis of Composite Chitosan and Durio zibethinus Seed and Its Applications as Adsorbent of Metal Ion Ni(II) Silvia Devi Eka Putri; Sri Mulijani; Komar Sutriah
ALCHEMY Jurnal Penelitian Kimia Vol 19, No 2 (2023): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.19.2.65948.197-209

Abstract

Nickel is one of the most dangerous heavy metals that impact water ecosystems and human health. In the study, natural and harmless composite materials such as biochar and chitosan were modified to build adsorbent composites and form optimal conditions for the adsorption of nickel heavy metal ions from contaminated wastewater. Biochar was prepared from Durio zibethinus seeds by hydrothermal method to form nanopowder. It was treated with acid, while chitosan was designed as nanopowder by hydrothermal method, also without acid treatment. Composite adsorbents were prepared by mixing biochar and chitosan with a ratio of 4:3 (w/w). Fourier Transform Infrared characterizes composite materials as adsorbents, biochar, and chitosan. The surface morphology of the adsorbent was evaluated by scanning electron microscopy. Furthermore, Langmuir, Freundlich, and Temkin isotherms determine the adsorbent's performance. In addition, batch adsorption experiments were carried out to measure the effect of solution pH, adsorbent dosage, and initial concentration of metal ions. Nickel ion adsorption by the composite adsorbent showed an adsorption capacity of 26.69 mg/g, a maximum removal efficiency of 89.39% at optimum conditions of pH 6, an adsorbent dose of 0.5 g, and a contact time of 200 minutes. This adsorption capacity was better than chitosan and durian seed adsorbents. The nickel ion adsorption process by composite adsorbent shows a pattern in the Temkin isotherm model. In contrast, the chitosan and Durio zibethinus seed adsorbents tended to follow the Langmuir and Freundlich isotherm models. In addition, the adsorption kinetics of the composite material showed pseudo-second-order kinetics, and the reaction was exothermic.
Performance of Doped Montmorillonite on Photosensitizer Based Natural Dyes Gardenia Jasminoides Sri Mulijani; Komar Sutriah; Gustini Syahbirin; Shabrina Shabrina
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 12, No 1 (2022): April
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v12i1.54786

Abstract

Dye Sensitized Solar Cell (DSSC) is an electrochemical cell that is able to convert solar energy from light to electrical energy. This technology is needed by the world as a renewable and environment friendly energy. In this study, we evaluate the consideration of modification montmorillonite and Gardenia jasminoides dyes may achieve better performance of DSSC by manufactured DSSC with modified TiO2 semiconductors using montmorillonite (MMT) and Nafion. Performance of DSSC was determined by potentiometer. Atomic force microscope was used to evaluate the characteristic of DSSC. The UV-vis results revealed that the dyes which is extracted from the Gardenia jasminoides content crocin and quercetin compounds. Modification DSSC contains ratio of MMT: nafion (50:50) exhibited highest power conversion efficiency value of 0.8316%. Topography of surface ensured the dyes have occupied surface area and able to promote electron to higher energy.  However, MMT and nafion capable to enhance potential of dyes as photosensitizer in DSSC. 
OPTIMASI PEMISAHAN SESIUM DI DALAM PELAT ELEMEN BAKAR TIPE U3Si2/Al PASCA IRADIASI MENGGUNAKAN METODE PENGENDAPAN KLOROPLATINAT Arif Nugroho; Komar Sutriah; Sri Mulijani; Triyono Basuki; Ahmad Ade Rofiqi; Noviarty; Helmi Fauzi Rahmatullah; Ganisa Kurniati Suryaman; Guswardani
Urania: Jurnal Ilmiah Daur Bahan Bakar Nuklir Vol. 30 No. 1 (2024): Urania: Jurnal Ilmiah Daur Bahan Bakar Nuklir
Publisher : Badan Riset dan Inovasi Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55981/urania.2024.8679

Abstract

Several methods for separating fission product ¹³⁷Cs from uranium isotopes (²³⁸U, ²³⁵U, ²³⁶U, and ²³⁴U) in U₃Si₂/Al fuel have been widely developed. Optimization and separation were performed using the chloroplatinate precipitation to establish a new cesium (Cs) separation method. The method developed in this research offers the potential to achieve higher-purity cesium precipitates. This study aims to develop a method of separating the ¹³⁷Cs isotope from U₃Si₂/Al fuel element plates (PEB) using chloroplatinate reagents. The procedure involves dissolving the pre-irradiation U₃Si₂/Al PEB and adding several elements such as Sm, Sr, Cs, and Nd to represent the composition of pre-irradiation PEB, simulating its original condition. The cesium precipitation process in the supernatant solution was carried out by adding HCl and NaOH to separate impurities from cesium. The precipitation was conducted by adding H₂PtCl₆ to precipitate and isolate cesium from other elements. The precipitation process was optimized by varying the temperature and precipitation time. The optimum precipitation conditions were achieved at a temperature of -3°C and a time of 10 minutes, resulting in a Cs2PtCl6 precipitate weighing 0.3361 g. XRD and SEM analyses were used to complement and verify the cesium separation results using the chloroplatinate precipitation method, showing a uniform distribution of all elements. The purity of the Cs2PtCl6 precipitate obtained was 100%, with a diffractogram pattern identical to the reference.
ANALISIS RADIONUKLIDA 137Cs DI DALAM PELAT ELEMEN BAKAR NUKLIR U3Si2/Al DENSITAS 4,8 gU/cm3 BURN UP 60% PASCA IRADIASI MENGGUNAKAN METODE KLOROPLATINAT Arif Nugroho; Komar Sutriah; Sri Mulijani; Triyono Basuki; Ahmad Ade Rofiqi; Boybul; Erlina Noerpitasari; Rosika Kriswarini; Juan Carlos Sihotang; Agus Jamaludin
Urania: Jurnal Ilmiah Daur Bahan Bakar Nuklir Vol. 30 No. 2 (2024): Urania : Jurnal Ilmiah Daur Bahan Bakar Nuklir
Publisher : Badan Riset dan Inovasi Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55981/urania.2024.9142

Abstract

Analysis of 137C isotopes in post-irradiation nuclear fuel is vital in determining burn up and fuel behavior during fission. The 137Cs isotope is used as input data for burn up calculations because it has a long half-life (30.17 years) and a large fission yield (6.026%). This study uses the chloroplatinate precipitation method to separate the 137Cs isotope from U3Si2/Al nuclear fuel with a density of 4.8 gU/cm³ with a burn up of 60% after irradiation. The separation process begins with cutting and dissolving the fuel sample, followed by the addition of CsNO₃ as a carrier solution and H₂PtCl₆ reagent to form Cs₂PtCl₆ precipitate. The results of the analysis using gamma spectrometry showed that the spectrum of the Cs₂PtCl₆ precipitate had the highest peak area of ​​67.6298 cps compared to the brown residue of 0.9165 cps and the supernatant of 0.2450 ​​cps. In addition, the results of this study showed an increase in the separation recovery value from 70% to 96.39%, which indicates the success of the separation of the 137Cs isotope from the U3Si2/Al fuel solution with a density of 4.8 gU/cm3 using the chloropaltinate precipitation method. The results of elemental mapping of the Cs₂PtCl₆ precipitate using SEM (scanning electron microscope) showed an even distribution of platinum (Pt), cesium (Cs), and chlorine (Cl) components, which shows the efficiency of this precipitation method. In addition, EDS (energy dispersive X-ray spectroscopy) analysis shows the elemental composition of the Cs₂PtCl₆ deposits. The three main elements identified are Pt, Cl, and Cs. The results of this study can provide an essential contribution to evaluating the performance of U3Si2/Al fuel with a density of 4.8 gU/cm3 after irradiation. They can be used for further research on Cs isotopes.