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All Journal CHEMISTRY PROGRESS Indonesian Journal of Chemical Science Science and Technology Indonesia Indonesian Journal of Chemistry Communications in Science and Technology IJEMS (Indonesian Journal of Environmental Management and Sustainability) Riau Journal of Empowerment Molekul: Jurnal Ilmiah Kimia Sains dan Matematika SRIWIJAYA JOURNAL OF ENVIRONMENT Makara Journal of Science Makara Journal of Technology Bulletin of Chemical Reaction Engineering & Catalysis Indonesian Journal of Material Research Prosiding Seminar Nasional Unimus
Risfidian Mohadi
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Sriwijaya University, Kampus UNSRI Indralaya, Jl. Palembang Prabumulih Km 32 Ogan Ilir 30662, South Sumatera
Agriculture, Biological Sciences & Forestry Humanities Astronomy Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Decision Sciences, Operations Research & Management Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Engineering Environmental Science Health Professions Materials Science & Nanotechnology Mathematics Mechanical Engineering Nursing Physics Public Health Social Sciences

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Journal : Science and Technology Indonesia

 1 
Removal of Anionic Direct Dye Using Zn/Al, Zn/Fe and Zn/Cr Layered Double Hydroxides Toward Interlayer Distance Palapa, Neza Rahayu; Taher, Tarmizi; Mohadi, Risfidian; Lesbani, Aldes
Science and Technology Indonesia Vol 4 No 3 (2019): July
Publisher : ARTS Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1299.16 KB) | DOI: 10.26554/sti.2019.4.3.70-76

Abstract

In order to minimize harmful effect of synthetic dye (direct yellow and direct violet) the capacity of Zn/Al, Zn/Cr and Zn/Fe layered double hydroxides of these contaminant was studied in this work. Batch adsorption experiment was conduct to investigate the effect of various operating parameters such as contact time, initial dye concentration and adsorption temperature in order to provide optimal condition in removal synthetic dye. Based on result, the sorption of direct dye onto LDHs followed pseudo-second-order rate model. The equilibrium adsorption data for both direct dye was fitted Freundlich isotherm model
Synthesis and Characterization of Zn/Al, Zn/Fe, and Zn/Cr Layered Double Hydroxides: Effect of M3+ ions Toward Layer Formation Palapa, Neza Rahayu; Saria, Yosi; Taher, Tarmizi; Mohadi, Risfidian; Lesbani, Aldes
Science and Technology Indonesia Vol 4 No 2 (2019): April
Publisher : ARTS Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1267.749 KB) | DOI: 10.26554/sti.2019.4.2.36-39

Abstract

Layered double hydroxides are composed by substitution of metal cation divalent and trivalent. Metal cation divalent and trivalent can be changed. In this work, effect metal cation trivalent (M3+) toward layer formation were studied. Synthesis of LDHs has used co-precipitation methods with molar ratio 3:1 and kept pH at 10. The result of synthesis was characterized by X-ray Diffraction (XRD) and Fourier Transform Infrared (FT-IR) analyses.
Removal of Methyl Orange in Aqueous Medium using ZnO/Bentonite as Semiconductor by Photocatalytic Process Priatna, Satria Jaya; Yuliana, Ayu; Zulkarnain; Melwita, Elda; Arsyad, Fitri Suryani; Mohadi, Risfidian
Science and Technology Indonesia Vol. 9 No. 3 (2024): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2024.9.3.539-545

Abstract

Pillarization of bentonites (from East Java) with ZnO semiconductors has been synthesized using co-precipitation methods into a ZnO/Bentonite composite and applied as a catalyst in a photocatalytic process to remove Methyl Orange (MO) dyes. The optimum pH condition of MO dyes is at pH 2 with a degradation rate of 22.91% (from 15 mg/L to 11.523 mg/L). The optimum ZnO/Bentonite catalyst weight condition is 200 mg, with a degradation rate of 29.11% (from 15 mg/L to 10.596 mg/L). The optimum time condition for UV lamp irradiation is 60 minutes, with a degradation rate of 64.92% (from 15 mg/L to 5.244 mg/L). The kinetics of MO photocatalytic reaction using ZnO/Bentonite catalyst follows the pseudo-first-order Langmuir Hinshelwood-Santosa kinetic model with photocatalytic reaction rate constant (k1) of 0.014 and photocatalytic equilibrium constant (K) of 0.012.
Selective Removal of Anionic and Cationic Dyes Using Magnetic Composites Fitri, Erni Salasia; Mohadi, Risfidian; Palapa, Neza Rahayu; Susila Arita Rachman; Lesbani, Aldes
Science and Technology Indonesia Vol. 9 No. 1 (2024): January
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2024.9.1.129-136

Abstract

Water is one of the most basic human needs, and dyes are one of the sources of water pollution. Since adsorption has proven to be effective in removing contaminants, it is the most widely used technique. In this adsorption, a LDH Zn-Al /magnetic biochar composite was used for dye removal. Zn-Al LDH, magnetic biochar, and LDH Zn-Al/biochar magnetic composite were successfully synthesized, based on XRD and FTIR studies. XRD analysis of the Zn-Al LDH material shows diffractions of (003), (006), (101), (012), (015), (107), and (110) around the 2theta angle at 10.29°, 20.07°, 29.59°, 32.12°, 34.02°, 48.06°, and 60.16° which are characteristic of LDH materials. In magnetic biochar and LDH Zn-Al/magnet biochar composites diffraction (220), (311), (422) and (440) at 2theta around 24.9°, 35°, 63° and 68.4° in these materials indicate the characteristics of carbon-based materials from biochar. FTIR analysis showed the appearance of a vibration peak at 1404cm−1 indicating the presence of C H groups contained in biochar. The characteristic double-layer hydroxy (M-O) vibrations below 1000 cm−1 also indicated that the composite preparation process had been successful. The study’s results show that cationic dyes are more easily adsorbed than anionic dyes. Specifically, the LDH Zn-Al/Magnetic Biochar composite more extensively absorbs the cationic dye malachite green.
High Performance of Ni-Al/magnetite Biochar for Methyl Orange Removal in Aqueous Solution Palapa, Neza Rahayu; Zahara, Zaqiya Artha; Mohadi, Risfidian; Royani, Idha; Lesbani, Aldes
Science and Technology Indonesia Vol. 9 No. 1 (2024): January
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2024.9.1.156-166

Abstract

Elevated concentrations of dyes in water have a significant impact on both the aquatic ecosystem and human well-being. The adsorption approach, which is cost-effective and simple to use, was chosen for color treatment. The adsorbents used in this study were Modified Layered Double Hydroxides (LDHs) and Magnetite Biochar (MBC). To prepare the Ni-Al/MBC composites, a technique called coprecipitation and hydrothermal was employed. The successful preparation of these composites was confirmed through the use of characterization tests including X-Ray Diffraction (XRD), Fourier Transform – Infra Red (FT-IR), Brunauer Emmet Teller (BET), and Vibrating Sample Magnometer (VSM). The study focused on analyzing the kinetics, isotherms, and thermodynamics of adsorption in order to anticipate the mechanism of Methyl Orange (MO) adsorption. Additionally, the regeneration process was investigated to assess the adsorbent's ability for repeated usage. The percentage of Ni-Al/MBC adsorbed during the first to fifth regeneration cycles was 86.940%, 82.545%, 70.752%, 56.244%, and 34.503% respectively. The duration of contact was 70 minutes, as determined by the Pseudo Second Order (PSO) equation, with an adsorption rate of 0.0030 g/mg.min. The Langmuir equation indicated a maximum adsorption capacity of 45.455 mg/g.
ZnAl LDH-based Derivative Materials as Photocatalysts: Synthesis, Characterization, and Catalytic Performance in Tetracycline Degradation Rohmatullaili; Ahmad, Nur; Erviana, Desti; Zultriana; Savira, Dila; Mohadi, Risfidian; Lesbani, Aldes
Science and Technology Indonesia Vol. 9 No. 2 (2024): April
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2024.9.2.457-469

Abstract

Layered Double Hydroxide (LDH)-derived materials exhibited different characteristics from LDH precursors. The conversion of ZnAl LDH into its derivative material has been carried out to find the best catalyst for TC degradation. ZnAl (LDH)-based catalysts in this study have been effectively synthesized using coprecipitation, calcination, and restacking procedures. ZnAl Layered Double Oxide (LDO) is derived from the calcination of ZnAl LDH at 500°C. ZnAl LDH was also modified by adding Garcinia mangostana pericarp extract (GME). XRD, FT-IR, UV-DRS, and SEM-EDX were used to investigate the synthesized catalyst. ZnAl LDH exhibited the typical LDH FT-IR spectra, whereas ZnAl LDO showed metal oxide-like spectra, and the ZnAl-GME composite displayed the combination spectra of precursor material. The ZnAl LDH XRD diffraction pattern exhibited the attributes of a layered material, whereas the other three catalysts did not. Calcination destroyed the layered structure of ZnAl LDH, whereas the addition of GME to LDH and LDO generated a single-layered composite. The modified ZnAl-GME composite showed a decrease in both particle size and bandgap energy. At an ideal pH of 5, the synthesized catalyst was used in a batch system photodegradation of 5 mg/L Tetracycline (TC), employing solar light irradiation. ZnAl LDO holds the most significant catalytic activity and structural stability through the fifth regeneration cycle, degraded TC up to 100% in 90 minutes.
Optimization of Nanoemulsion Formula Containing Erythromycin with VCO and Varying Concentrations of Tween-80 and PEG-400 Mardiyanto; Mohadi, Risfidian; Fithri, Najma Annuria; Kurniawan, Gilang
Science and Technology Indonesia Vol. 9 No. 3 (2024): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2024.9.3.697-709

Abstract

Erythromycin, a macrolide antibiotic is classified into Biopharmaceutical Classification System (BCS) class II which has low solubility in water. The low solubility corresponds to the bioavailability in the blood. One strategy to increase the solubility of Erythromycin is the formulation of erythromycin in nanoemulsion. This research aims to form nanoemulsion using the PIT (Phase Transition Temperature) method for obtaining the optimum formula of erythromycin nanoemulsion using virgin coconut oil (VCO) can be found with varying concentrations of Tween 80 surfactant and PEG 400 cosurfactant. The selection of the optimum formula was assisted by Design Expert software with the Factorial design method 22. The basis for determining the optimum formula is based on the results of organoleptic characterization tests, adsorption efficiency (%EE), percent transmittance, viscosity test, pH test, and stability test. The optimum formula was nanoemulsion which had a concentration of Tween 80 25% and PEG 400 25% as a desirability value of <1. The results of the optimum formula showed that the particle size was 170.6±12.8594 nm, polydispersity index (PDI) 0.403±0.04406, and zeta potential -8.8667±0.25697 mV and had an appropriate stability without phase separation during stability test.
Development of Nanofiber Made of Nanocellulose with Oil Encapsulation of Eucalyptus sp. Sari, Wida Fatma; Haryati, Sri; Mohadi, Risfidian
Science and Technology Indonesia Vol. 10 No. 4 (2025): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.4.1074-1086

Abstract

The amalgamation of natural polymers derived from lignocellulosic waste with synthetic polymers is a potential avenue for producing high-value products through nanotechnological innovations. Nanofibers are a significant application of nanotechnology and is now being explored as an alternative method for treating lignocellulosic waste. Nanofiber is a fiber generated by an electrospinning device. Cellulose obtained from lignocellulose can be transformed into valuable products, including nanocellulose. This project entails the synthesis of nanofibers via the combination of natural and synthetic polymers, an innovative approach in the field. Natural polymers are derived from alginate and nanocellulose, whilst synthetic polymers are produced from Poly Vinyl Alcohol (PVA). This study employs nanofibrils in healthcare, specifically as a cartridge filter in masks infused with Eucalyptus sp. This study sought to identify the optimal method for producing nanofibers with a minimal pore size by varying the concentrations of PVA (4%, 8%, 12%, and 16%) and nanocellulose (2.5%, 5%, and 7.5%). This research employs a combination of methods to produce nanocellulose of suitable size, an innovative process. The pretreatment process utilizes a blend of chemical and physical methods. Nanocellulose is synthesized using varying concentrations of sulfuric acid (25%, 50%, and 75%) during the acid hydrolysis process. The optimal nanocellulose size was attained at a sulfuric acid concentration of 50% (40oC, 10 minutes), as evidenced by a mean diameter of 484.3 nm. The amalgamation of physical and chemical methods has demonstrated efficacy in generating a beneficial pore size distribution in nanocellulose. Nanofibers are synthesized utilizing 12% PVA, 0.5% alginate, 2.5% nanocellulose, and 1% Eucalyptus sp. over 30 hours (3 mL), resulting in an average diameter of 200 nm for the created nanofibers. Concurrently, the nanofiber produced in the absence of Eucalyptus sp. exhibited a diameter of 240 nanometers.
Co-Authors Agustiarini, Vitry Aldes Lesbani Alfarizi, Muhammad Afif Amiruddin Supu Amri Amri Amri Andreas, Roy Apriani, Elsa F. Arsyad, Fitri Suryani Badri, Arini Fousty Broekaert, José A.C. Dedi Setiabudidaya Elfita Elfita . Eliza . Eliza Eliza Erviana, Desti Fahma Riyanti Fitri, Erni Salasia Hakim, Yusuf Mathiinul Hanifah, Yulizah Harun, Muhammad Umar Hesti A. Harahap, Hesti Hidayatullah, Muhammad Idha Royani Jefri Jefri Juleanti, Novie Karvenia, Icha Aulia Kiki Anggraini, Kiki Komala Syari Kurniawan, Gilang Liasari, Beta Riana Lingga, Fitra Wahyuni Mardianto Mardiyanto Mardiyanto Mardiyanto Mardiyanto, Melwita, Elda Mustafa Kamal Najma Annuria Fithri, Najma Annuria Normah Normah Normah Normah, Normah Nova Yuliasari Nur Ahmad Nur Ahmad, Nur Nur khakim, Mokhamad Yusup Nurlisa Hidayati Nur’aini, Siti Prayitno, Muhammad Bambang Rakhmawati Farma Ramadhan, Jeri Rohmatullaili Rohmatullaili, Rohmatullaili Sabat Okta Ceria Sitompul, Sabat Okta Ceria Sari, Wida Fatma Satria Jaya Priatna, Satria Jaya Savira, Dila Sherly Agustina, Sherly Siregar, Patimah Mega Syah Bahar Nur Sitanggang, Jonra P. Siti Sailah, Siti Soerya, Balada Sri Haryati Suheryanto SUMIATI, Supriyadi Supriyadi Susila Arita Tarmizi Taher Wardhana, Singgih Tri Wibiyan, Sahrul Wijaya, Alfan Yosi Saria Yosine Susie Yuliana, Ayu Zahara, Zaqiya Artha Zulkarnain Zultriana