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All Journal Indonesian Journal of Chemistry Communications in Science and Technology Indonesian Journal of Agricultural Research Bulletin of Chemical Reaction Engineering & Catalysis Indonesian Journal of Material Research
Wijaya, Alfan
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Agriculture, Biological Sciences & Forestry Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Economics, Econometrics & Finance Electrical & Electronics Engineering Energy Engineering Environmental Science Social Sciences Veterinary

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Storage Stability of Additive-free Salacca sp. Fruit Leather Purwandari, Umi; Mojiono, Mojiono; Putri, Ninik Wulandari K; Efendi, Miftakhul; Wijaya, Alfan
Indonesian Journal of Agricultural Research Vol. 1 No. 3 (2018): InJAR, Vol. 1, No. 3, November 2018
Publisher : Talenta Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1508.345 KB) | DOI: 10.32734/injar.v1i3.495

Abstract

We developed additive-free fruit leather made from snake fruit (Salacca sp.), one of the exotic fruits of Madura, Indonesia. Mature snake fruit variety native of Bangkalan Regency was peeled, the seed was discarded, and flesh was blanched for 5 minutes, cooled and then crushed in an electric blender to form a smooth slurry. The slurry was then cooked until thick, spread onto a flat surface, and then dried in an oven at 60°C until dry. Fruit leather with a water content of around 10% was kept in aluminium foil or polypropylene plastic bag at 25 and 35°C for 3 weeks. Every week, fruit leather was examined for tensile strength, water activity, colour (L, a b*values), and titratable acidity. Sensory analysis was performed using ten semi-trained panellists to score hardness, chewiness, sweetness, astringency, aroma, shininess, and cohesiveness. Results indicated that tensile strength apparently increased during storage. Polypropylene bag showed lower water activity and value, but higher titratable acidity of fruit leather. Storage time increased water activity, titratable acidity, but reduced all colour parameters. Higher storage temperature led to higher L and b values. On the contrary, sensory analysis results indicated the limited effect of factors studied. The shininess of fruit leather reduced with the progress of storage, and cohesiveness increased in the first week of storage only, followed by constant reduce towards the storage time. Astringency in snake fruit is a limiting factor. However, snake fruit leather showed moderate level (4.6 out of 9 score) of astringency.
Removal of Cr(VI) from aqueous solution by biochar derived from rice husk Mohadi, Risfidian; Palapa, Neza Rahayu; Taher, Tarmizi; Siregar, Patimah Mega Syah Bahar Nur; Normah; Juleanti, Novie; Wijaya, Alfan; Lesbani, Aldes
Communications in Science and Technology Vol 6 No 1 (2021)
Publisher : Komunitas Ilmuwan dan Profesional Muslim Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21924/cst.6.1.2021.293

Abstract

In this work, biochar produced from Indonesian rice husks. Then used as adsorbent of Cr(VI) in aqueous solution. The XRD pattern of biochar showed the characterization pattern at 23º (002) reflection, appearance of silicate oxide, and the carbon vibrations. The surface area and SEM morphologies confirmed that after pyrolysis treatment the surface of rice husk has changed. The surface area of biochar increased after thermal treatment. The adsorption study of Cr(VI) by biochar demonstrate 2nd-order reaction, and Langmuir isotherm models. The maximum adsorption capacity of biochar derived rice husk to adsorb Cr(VI) is 161.290 mg/g, and biochar showed the good potential as reuseable adsorbent to remove heavy metal in aqueous solution.
Mg/Al-CH, Ni/Al-CH and Zn/Al-CH, as adsorbents for Congo Red removal in aqueous solution Siregar, Patimah Mega Syah Bahar Nur; Normah; Juleanti, Novie; Wijaya, Alfan; Palapa, Neza Rahayu; Mohadi, Risfidian; Lesbani, Aldes
Communications in Science and Technology Vol 6 No 2 (2021)
Publisher : Komunitas Ilmuwan dan Profesional Muslim Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21924/cst.6.2.2021.547

Abstract

In this study, chitosan was extracted from shrimp shells by demineralization and deproteination processes. The extracted chitosan was used to modify the layered double hydroxide and used as an adsorbent for the removal of congo red from aqueous solutions. Composites were successfully synthesized using M2+/Al (M2+ = Zn, Mg, Ni) and chitosan (CH) and the samples obtained were characterized using XRD and FTIR. The X-ray diffraction (XRD) pattern appeared at the layered double hydroxide peak of 2? = 11.63°; 23.00°; 35.16°; and 61.59° and chitosan at 2? = 7.93° and 19.35. The composite appearing in the layered double hydroxide and chitosan indicated that the composite material has been successfully synthesized. The XRD diffraction patterns of Zn/Al-CH, Ni/Al-CH, and Mg/Al-CH showed low crystallinity. The Fourier Transform Infrared (FTIR) spectra verifying absorption spectrum showed the presence of two bands at 3448 cm-1, 1382cm-1 characteristic to both chitosan and LDH. Adsorption of Congo Red (CR) followed the pseudo-second-order and Langmuir isotherm models. The adsorption capacities of Zn/Al-CH, Ni/Al-CH, and Mg/Al-CH were 181.818 mg/g, 227.273 mg/g, and 344.828 mg/g, respectively. The layered double hydroxide-chitosan composite adsorption was endothermically characterized by positive enthalpy and entropy values. On the other hand, the adsorption spontaneously was characterized by a negative Gibbs free energy value. The composites in this study were formed from LDH modified from chitosan extracted from shrimp shells to form Zn/Al-CH, Ni/Al-CH, and Mg/Al-CH. The results of the characterization showed a number of characteristics that resembled the constituent materials in the form of LDH and chitosan. After being applied as an adsorbent to absorb Congo red dye, it then showed the most effective results using Mg/Al-CH adsorbent with an adsorption capacity of 344.828 mg/g.
Efficient Adsorption of Methylene Blue Dye Using Ni/Al Layered Double Hydroxide-Graphene Oxide Composite Amri, Amri; Wibiyan, Sahrul; Wijaya, Alfan; Ahmad, Nur; Mohadi, Risfidian; Lesbani, Aldes
Bulletin of Chemical Reaction Engineering & Catalysis 2024: BCREC Volume 19 Issue 2 Year 2024 (August 2024)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.20121

Abstract

To address environmental pollution, we developed Ni/Al layered double hydroxide-graphene oxide (Ni/Al-GO) adsorbent materials for the purpose of eliminating methylene blue (MB) dye pollutants. The adsorption process was explored by examining many experimental factors, including temperature, regeneration/reuse procedure, pH, and time, and their effects on the material. The appropriate model for the isotherm is the Langmuir isotherm. The Ni/Al-GO material achieved a maximum adsorption capacity of 61.35 mg/g for MB dye at a temperature of 60 °C. The thermodynamic characteristics indicate that the adsorption process is both endothermic and spontaneous as the temperature increases. The regeneration method demonstrated that the Ni/Al-GO material has a highly stable structure, enabling it to be utilized for five cycles with a remarkable regeneration rate of 93.49% in the fifth cycle. The pH that yielded the best results for all materials was pH 10, and the kinetic model demonstrated a pseudo second-order behavior. Copyright © 2024 by Authors, Published by MKICS and BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Efficient Adsorption of Cr(VI) from Aqueous Solutions Using Composites Modified with Ni/Al LDH and Keggin Type Compounds Normah, Normah; Adhiyanti, Nurmalina; Sayeri, Rabellia Juladika; Wijaya, Alfan
Indonesian Journal of Material Research Vol. 2 No. 2 (2024): July
Publisher : Magister Program of Material Science Graduate School of Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/ijmr.20242228

Abstract

This study aims to synthesize the NiAl-LDH/K4[α-SiW12O40] composite using the coprecipitation method and evaluate its ability to adsorb Cr(VI) from aqueous solutions. The material characterization showed a significant increase in the specific surface area of the composite compared to pure NiAl-LDH, contributing to an enhanced Cr(VI) adsorption capacity. XRD and FT-IR results confirmed the successful synthesis and integration of K4[????-SiW12O40] into the NiAl-LDH structure. At the same time, BET analysis indicated that the specific surface area of the composite doubled compared to pure NiAl-LDH. The adsorption kinetics data indicated that the adsorption process followed the Pseudo-Second-Order (PSO) model with an R2 value close to 1, suggesting the dominance of chemisorption in the Cr(VI) adsorption mechanism. Isotherm analysis showed that the Freundlich model was more suitable than the Langmuir model, indicating that adsorption occurred on a heterogeneous surface with multilayer formation. The Cr(VI) adsorption capacity of the NiAl-LDH/K4[α-SiW12O40] composite reached 17.123 mg/g, higher than that of pure NiAl-LDH at 188.68 mg/g. The Cr(VI) adsorption process involved chemical interactions between Cr(VI) and functional groups on the adsorbent surface, complex formation, and precipitation.
Optimization of Desulfurization of 4-Methyldibenzothiophene and 4,6-Dimethyldibenzothiophene Using Mg/Al Layered Double Hydroxide Equipped with ZnO/TiO2 Amri, Amri; Ahmad, Nur; Wibiyan, Sahrul; Wijaya, Alfan; Mardiyanto, Mardiyanto; Royani, Idha; Mohadi, Risfidian; Lesbani, Aldes
Indonesian Journal of Chemistry Vol 24, No 4 (2024)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.88790

Abstract

The growth of heavy industry leads to an increase in sulfur dioxide emissions, impacting health, economy, and the fulfilment of the ecological needs for society. Sulfur removal is carried out using the oxidative desulfurization (ODS) method. In this study, layered double hydroxide materials of Mg/Al, Mg/Al-TiO2, and Mg/Al-ZnO were successfully synthesized and analyzed using X-ray diffraction (XRD), Fourier-transform infrared (FTIR), and scanning electron microscope-energy dispersive spectroscopy (SEM-EDS) techniques. Those materials are used as catalysts for the desulfurization of 4-methyldibenzothiophene (4-MDBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT). Composite Mg/Al catalysts with metal oxides provide superior desulfurization process efficiency and enhanced stability, making them highly effective for repeated use. The conversion percentage of desulfurization of 4-MDBT and 4,6-DMDBT increases with time. The n-hexane is a suitable solvent for desulfurization of 4-MDBT and 4,6-DMDBT. All catalysts exhibit significant heterogeneity that greatly aids in the separation process.
Preparation of Hydrochar from Longan Peel: A Promising Adsorbent for Cationic Dye Removal in Aqueous Solutions Wijaya, Alfan; Ardiansyah, Redo; Augustiara, Elsha; Fajri, Shahibul
Indonesian Journal of Material Research Vol. 2 No. 3 (2024): November
Publisher : Magister Program of Material Science Graduate School of Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/ijmr.20242344

Abstract

This study successfully prepared longan peel hydrochar via hydrothermal carbonization, characterized and evaluated for its adsorption capacity of cationic dyes malachite green (MG) and rhodamine B (RhB) in aqueous solution. Material characterization through XRD analysis revealed diffraction peaks indicative of carbonaceous content, supported by FTIR results showing OH, C-O, and C-O-C functional groups. The BET analysis showed a surface area of 18.712 m2/g, and SEM images displayed a heterogeneous, irregular surface morphology with spherical particles. The longan peel hydrochar exhibited adsorption capacities of 117.647 mg/g for MG and 50.505 mg/g for RhB, with MG showing greater selectivity, as demonstrated through dye mixture adsorption tests. The adsorption process was spontaneous, endothermic, and conformed to the pseudo-second-order kinetic model. Adsorption of MG followed the Freundlich isotherm, while RhB adsorption conformed to the Langmuir isotherm. Additionally, the hydrochar exhibited reusability for up to two adsorption cycles, indicating its potential as an effective adsorbent for cationic dye removal from aqueous solutions.
CuAl-LDH Modified with Filamentous Macroalgae for Anionic Dyes Removal: A Study on Selectivity, Adsorption Efficiency, and Regeneration Wijaya, Alfan; Hanum, Laila; Melwita, Elda; Lesbani, Aldes
Bulletin of Chemical Reaction Engineering & Catalysis 2024: BCREC Volume 19 Issue 4 Year 2024 (December 2024)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.20223

Abstract

Continuous modifications of Layered Double Hydroxides (LDH) materials are essential to enhance their structural stability and improve their capacity for pollutant adsorption, addressing the need for more effective remediation strategies in environmental applications. This research study has proposed the preparation of CuAl-LDH supported filamentous macroalgae of Spirogyra sp. (CuAl-LDH/SA) via coprecipitation and hydrothermal methods. The prepared CuAl-LDH/SA composites were investigated for the adsorption of direct yellow 12 (DY) and remazol red (RR) dyes in batch mode experiments. The structure and morphology of the prepared CuAl-LDH/SA were identified by X-ray Diffraction (XRD), Fourier Transform Infra Red (FT-IR), (Brunauer-Emmett-Teller) BET surface area, Thermogravimetry / Differential Thermal Analyzer (TG/DTA), and Scanning Electron Microscope (SEM). For the adsorption process, the effects of initial pH, contact time, initial concentration, temperature, adsorption selectivity, and adsorbent regeneration, as well as kinetics, isotherms, and thermodynamics were studied. The adsorption selectivity test resulted in the RR dye being more selective compared to DY. The maximum capacities for RR adsorption were 72.464 mg/g (pH = 2, 150 min, 303 K). CuAl-LDH/SA can be regenerated for 4 cycles with a percent removal of 29.32%. The adsorption process followed the intraparticle diffusion kinetics model and Langmuir isotherm. Thermodynamic studies showed that the adsorption of RR using CuAl-LDH/SA was endothermic and spontaneous. The results of this study indicate that CuAl-LDH/SA composite material shows potential material in the removal of anionic dyes from aqueous solutions. Copyright © 2024 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).
Optimization of Hydrothermal Carbonization Time of Dimocarpus longan Peel: Adsorption Selectivity and Regeneration Performance for Dyes Wijaya, Alfan; Ahmad, Nur; Utami, Hasja Paluta
Indonesian Journal of Material Research Vol. 3 No. 1 (2025): March
Publisher : Magister Program of Material Science Graduate School of Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/ijmr.20253150

Abstract

This study investigates the hydrothermal carbonization (HTC) process of Dimocarpus longan peel for the development of a selective and regenerable adsorbent for cationic dye removal. The hydrochar was synthesized at 190°C with varying carbonization durations (4–12 hours) and characterized using XRD and FTIR analysis. XRD analysis revealed the formation of an amorphous carbon phase, particularly at longer HTC durations, with the most optimized structure observed at 10 hours. FTIR spectra confirmed that hydrothermal carbonization preserved the primary functional groups while modifying their intensity. Adsorption experiments using a binary dye system (malachite green-MG and rhodamine B-RhB) demonstrated that the hydrochar exhibited higher selectivity for MG, achieving a removal efficiency of 81.78%, compared to 41.88% for RhB. Desorption studies indicated that ethanol and acetone were the most effective desorbing agents, with desorption efficiencies of 18.99% and 18.14%, respectively, while water and acidic conditions showed minimal dye release. Regeneration tests revealed a gradual decline in adsorption capacity over three cycles, with removal efficiencies decreasing from 73.23% to 42.17%, indicating partial loss of adsorption sites and possible structural degradation. These findings suggest that Dimocarpus longan peel-derived hydrochar, particularly at 10-hour HTC processing, is a promising adsorbent for selective cationic dye removal. However, further optimization of regeneration techniques is necessary to improve its reusability and long-term performance.
Comparative Assessment of Procion Red Removal Using Magnetite-Based Composites with Humic Acid, Activated Charcoal, and Lignin Ahmad, Nur; Wijaya, Alfan; Amri
Indonesian Journal of Material Research Vol. 3 No. 3 (2025): Future Issue: November
Publisher : Magister Program of Material Science Graduate School of Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/ijmr.20253368

Abstract

This investigation presents the synthesis and comparative assessment of three magnetite-based composite adsorbents, including Magnetite Humic Acid (MA), Magnetite Activated Charcoal (MB), and Magnetite Lignin (MC), aimed to remove Procion Red (PR) from aqueous solutions. The characterization of the materials was conducted through XRD, BET, and FTIR analyses, which validated the successful synthesis of magnetite and its interactions with the respective organic components. The point of zero charge (pHpzc) values obtained were 4.75, 5.09, and 4.10 for MA, MB, and MC, respectively. Adsorption experiments were performed under these pHpzc conditions to mitigate electrostatic influences. Kinetic investigations demonstrated that the adsorption process adhered to a pseudo-second-order model, signifying that chemisorption was the prevailing mechanism. Furthermore, the Langmuir isotherm yielded the most accurate representation of the equilibrium data, implying the occurrence of monolayer adsorption. MB demonstrated the highest adsorption capacity of PR, recorded at 52.632 mg/g at a temperature of 50oC. This observation underscores the benefits associated with its elevated surface area and the effective dispersion of Fe3O4 particles within the activated carbon matrix. The comparative analysis elucidates the impact of organic matrix selection on surface characteristics, interaction dynamics, and the overall efficacy of adsorption processes. This study presents novel findings regarding the development of natural carbon-magnetite composites aimed at enhancing the efficiency of dye removal processes.
Co-Authors Adhiyanti, Nurmalina Aldes Lesbani Amri Amri Amri Ardiansyah, Redo Augustiara, Elsha Efendi, Miftakhul Fajri, Shahibul Hasja Paluta Utami, Hasja Paluta Idha Royani Juleanti, Novie Laila Hanum Mardiyanto Mardiyanto Melwita, Elda Mojiono, Mojiono Normah Normah Normah Normah, Normah Nur Ahmad, Nur Putri, Ninik Wulandari K Risfidian Mohadi Sayeri, Rabellia Juladika Siregar, Patimah Mega Syah Bahar Nur Sitanggang, Jonra P. Tarmizi Taher UMI PURWANDARI Wibiyan, Sahrul