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All Journal Jurnal Sains Materi Indonesia Bulletin of Chemical Reaction Engineering & Catalysis Science and Technology Indonesia Indonesian Journal of Chemistry Jurnal Abdidas Makara Journal of Science Environmental and Materials Bulletin of Chemical Reaction Engineering & Catalysis
Yuni Krisyuningsih Krisnandi, Yuni Krisyuningsih
Department Of Chemistry, FMIPA, Universitas Indonesia, Depok
Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Control & Systems Engineering Education Energy Engineering Environmental Science Health Professions Materials Science & Nanotechnology Mathematics Physics Public Health Social Sciences Other

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Journal : Makara Journal of Science

 1 
Adsorption of Phosphate Ion in Water with Lithium-Intercalated Gibbsite Sihombing, Riwandi; Krisnandi, Yuni Krisyuningsih; Widya, Rahma; Luthfiyah, Siti Zahrotul; Yunarti, Rika Tri
Makara Journal of Science Vol. 19, No. 4
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In order to enhance adsorption capacity of gibbsite (Al(OH)3 as an adsorbent for the adsorption of phosphate in water, gibbsite was modified through lithium-intercalation. The purification method of Tributh and Lagaly was applied prior to intercalation. The Li-Intercalation was prepared by the dispersion of gibbsite into LiCl solution for 24 hours. This intercalation formed an cationic clay with the structure of [LiAl2(OH)6]+ and exchangeable Cl- anions in the gibbsite interlayer. A phosphate adsorption test using Lithium-intercalated gibbsite (LIG) resulted in optimum adsorption occurring at pH 4.5 with an adsorption capacity of 11.198 mg phosphate/g LIG which is equivalent with 1.04 wt% LIG. The adsorption capacity decreased with decreasing amounts of H2PO4-/HPO4- species in the solution. This study showed that LIG has potential as an adsorbent for phosphate in an aqueous solution with pH 4.5–9.5.
Fe(III) Oxide-modified Indonesian Bentonite for Catalytic Photodegradation of Phenol in Water Pradisty, Novia Arinda; Sihombing, Riwandi; Howe, Russell Francis; Krisnandi, Yuni Krisyuningsih
Makara Journal of Science Vol. 21, No. 1
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Phenol, which is a major organic pollutant, is usually detected in industrial wastewater, and thus the wastewater should be processed further before discharged into water bodies. Application of heterogeneous catalysis using natural-basedmaterials is known to be effective and environmentallyfriendlyinremoving hazardous substances in water. In this study, local natural bentonite from the Tapanuli region in Indonesia was modified to eliminate dissolved phenol. Elimination by photodegradation reaction was conductedinaphoto-Fenton system utilizing Fe(III) oxide-modifiedbentonite (Fe-B) as catalyst. Fe-B was prepared byacation exchanging process using mixture solutions of NaOH and FeCl3 with OH/Femolar ratio of 2:1 and calcined at 300 °C. Material characterization was performed by X-ray diffraction (XRD), low-angle XRD, Fourier transform infrared spectroscopy and atomic absorption spectroscopy. The reaction components consisted of ultraviolet Clight, H2O2, and Fe-B, and they were processed in a batch reactor. The role of each component was analyzed by a series of reaction conditions (i.e., adsorption, photolysis, H2O2effect, Fenton, and homogeneous photo-Fenton). The heterogeneous photo-Fenton system was found to be essential for phenol degradation, as none of the reaction conditions caused total phenol removal in the 180 min reaction time. To conclude, heterogeneous photo-Fenton gave the highest photodegradation activity, and the best experimental condition for 1.10 mM phenol removal was 5 g L-1 catalyst, 78.35 mM H2O2, and 90 minreaction time.
Grass-Like Structured Mesoporous Carbon as an Acid Red 119 Dye Adsorbent Krisnandi, Yuni Krisyuningsih; Priantini, Tania; Faisal, Muhammad; Yunarti, Rika Tri; Saragi, Indah Revita; Gunlazuardi, Jarnuzi
Makara Journal of Science Vol. 23, No. 4
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Grass-like structured mesoporous carbon was prepared by the soft-template method using triblock copolymer Pluronic F127, affording an organic–organic composite structure between phloroglucinol and formaldehyde. Thermogravimetric analysis revealed that the as-synthesized mesoporous carbon is stable to 900 °C, and X-Ray Diffraction (XRD) analysis confirmed the presence of carbon material structures at 2θ values of 22.020° and 42.420°. A hysteresis loop at relative partial pressures (P/Po) between 0.45 and 0.85 was observed in the N2 adsorption isotherm, indicating that the solid material exhibits mesoporous characteristics, with a homogeneous pore size distribution of 8.863 nm. Scanning Electron Microscope (SEM) images revealed that the bulk carbon surface exhibits a uniform grass-like structure. Furthermore, the as-synthesized mesoporous carbon was investigated for the adsorption of a diazo dye Acid Red 119, and it exhibited an adsorption capacity of 217.7389 mg/g; this capacity is 1.53 times greater than that of commercial activated carbon. Therefore, this mesoporous carbon is a potential adsorbent for the treatment of synthetic coloring waste.
ZnO/SiO2 Composite as Catalyst for the Transformation of Glycerol to Glycerol Carbonate Krisnandi, Yuni Krisyuningsih; Eckelt, Reinhard; Atia, Hanan; Adam, Martin; Saragi, Indah Revita; Martin, Andreas; Richter, Manfred
Makara Journal of Science Vol. 24, No. 1
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Zinc oxide/porous silica (ZnO/SiO2) composite was used as a catalyst to transform glycerol to glycerol carbonate (GC), a chemical intermediate and monomer for the synthesis of new functionalized polymers. The ZnO/SiO2 catalyst was prepared using the direct precipitation method by mixing zinc sulfate solution with Aerosil 300 silica suspension and adding potassium oxalate solution. Catalytic transformation used glycerol and urea (molar ratio = 1:1) at 140 °C, 40 mbar, and various reaction times (1–6 h). The ZnO catalyst exhibited a high percentage of glycerol conversion of 82.38%; however, the yield of GC and selectivity toward GC were relatively low (i.e., 33.33% and 40.46%, respectively). The presence of silica support (ZnO/(x)SiO2 increased the selectivity toward GC and yield of GC to 74.40% to 77.83% and 57.86% to 64.30%, respectively. Furthermore, although its crystallinity decreased, the reused ZnO/(60)SiO2 catalyst still exhibited a high activity. The scanning transmission electron microscopy image indicated the migration of ZnO on the surface of the composite and the possibility of ZnO-glycolate formation, which were also confirmed by FTIR measurement. Nevertheless, these results showed that ZnO/SiO2 is a promising catalyst for the transformation of glycerol to GC.
Natural Aluminosilicate-based Y Zeolite for Catalytic Cracking of n-Hexadecane Khatrin, Irena; Saragi, Indah Revita; Ekananda, Rizki; Hanna, John Vincent; Griffith, Benyamin E; Krisnandi, Yuni Krisyuningsih
Makara Journal of Science Vol. 24, No. 2
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Natural zeolite and kaolin are abundant in Indonesia especially in Java and Belitung islands. These materials generally contain high aluminosilicate minerals that can be used as silica and alumina sources for the formation of NaY zeolite. This research aimed to identify the modification of NaY zeolite structure using Bayat natural zeolite as alumina source and Belitung kaolin as silica source and its catalytic activity for n-hexadecane cracking. Pretreatment of materials were performed in several steps: activation, purification, fragmentation for Bayat–Klaten natural zeolite, and silica extraction for Belitung kaolin. The synthesis of NaY was performed hydrothermally using seed-assisted method with crystallization times of 24 and 48 h. The surface area analysis showed a typical surface area of microporous zeolite (i.e., a pore diameter of 1.897 nm) and surface area of 309.4 cm2/g. Meanwhile, powder X-ray diffraction characterization showed that the as-synthesized materials have the structure of NaY zeolite. The optimum crystallization time was 24 h with Si/Al ratio of 4.10. Furthermore, both synthetic and natural sourced NaY zeolites were converted into HY zeolites and employed as cracking catalyst of n-hexadecane in a fixed-bed reactor at 500 °C for 75 s. The natural sourced HY resulted in 59.80% conversion and 59.80% yield of gasoline product (C9–C12). These values were lower than the results given by synthetic HY (80%).
Magnetically Separable Fe3O4/SiO2/TiO2 Photocatalyst Composites Prepared through Hetero Agglomeration for the Photocatalytic Degradation of Paraquat Gunlazuardi, Jarnuzi; Fisli, Adel; Ridwan, Ridwan; Krisnandi, Yuni Krisyuningsih; Robert, Didier
Makara Journal of Science Vol. 25, No. 4
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A photocatalyst supported on magnetic material allows the simple technique by using an external magnetic material to separate photocatalyst from the treated water. Thus, it is a magnetically separable nanoparticles photocatalyst (MSNP). The use of superparamagnetic nanoparticles that do not pose spontaneous magnetic moment thus could be dispersed in water and can be recollected easily by an external magnetic bar. We prepare Fe3O4/SiO2/TiO2 composite by hetero agglomeration of Fe3O4/SiO2 and TiO2 at a pH range of 3 to 6.2 in an aqueous slurry.The Fe3O4/SiO2 was prepared via co-precipitation of iron (II) and iron (III) ionic solution containing ammonium hydroxide and sodium silicate. The prepared composites were characterized by XRD, TEM, FTIR, and VSM, while the photocatalytic activities were tested toward paraquat in water. Based on zeta potential values, the Fe3O4/SiO2and TiO2 were being hetero agglomerated at pH 5 to obtain Fe3O4/SiO­2/TiO2 composite. The XRD characterization confirmed the presence of anatase, rutile, and magnetite crystal phases. TEM images showed that the Fe3O4 was covered by SiO2 and randomly attached to TiO2. The observed FTIR peak at 940-960 cm-1 attributed to -Si-O-Ti- bonding mode, ensuring photocatalyst (TiO2) adherence to the Fe3O4/SiO2 cluster. The prepared Fe3O4/SiO2/TiO2 composite showed good photocatalytic activity for the paraquat removal and showed a good magnetic property (VSM measurement)
Antibacterial Testing on Silver/Zinc Oxide Nanoparticles/Organoclay Reinforced Chitosan Biocomposites Muiz, Lisna Junaeni; Juwono, Ariadne Lakshmidevi; Paputungan, Zulkarnaen; Krisnandi, Yuni Krisyuningsih
Makara Journal of Science Vol. 27, No. 3
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Herein, bionanocomposites of chitosan (CS)/silver nanoparticle/organoclay/zinc oxide nanoparticle (CS/Ag/OC/ZnO) were prepared for antibacterial food packaging. This study examines the time variation in the AgNP synthesis method by comparing local (74˗85% deacetylated) and commercial chitosan (75%˗85% deacetylated) as a reducing and capping agent and seeks to reconstruct the optimum ratio formulations of AgNPs and ZnONPs in bionanocomposites for food packaging. The results reveal that the synthesis of AgNPs was successfully carried out using a local chitosan solution as a reducing and capping agent. The CS/Ag/OC/ZnO films exhibit structural, mechanical, and optical properties suitable for food packaging and antibacterial activity on Staphylococcus aureus and Escherichia coli. The relative inhibition zone increased with increasing numbers of AgNPs and ZnONPs. The inhibition zone values indicated that E. coli and S. aureus bacteria were sensitive to the film, namely 12.5 ± 1.5 mm, and 16 ± 0.0 mm, respectively.
Co-Authors Adam, Martin Adel Fisli Ahmed, Sabeel Alika Rizki Anggraeni Amanullah, Duha Rushida Anastasia Agnes Anita Nur Ramadhani Anya Prilla Azaria Atia, Hanan Bayu Adi Samodro Dita Arifa Nurani Eckelt, Reinhard Ekananda, Rizki Endang Saepudin, Endang Fahriansyah, Irsan Griffith, Benyamin E Hanna, John Vincent Hanzhola Gusman Riyanto Hedi Surahman Herlina, Idra Iman Abdullah Iman Abdullah Iman Abdullah Jarnuzi Gunlazuardi Juwono, Ariadne Lakshmidevi Khanifah Khanifah Khatrin, Irena Luthfiyah, Siti Zahrotul Marintan, Marchia Marthalena Martin, Andreas Muhammad Faisal Muhammad Ridwan Muiz, Lisna Junaeni Mulyadi, Andita Junia Noer Fadlina Antra Novia Arinda Pradisty Nurani, Dita Arifa Nurhalimah, Dede Paputungan, Zulkarnaen Pradisty, Novia Arinda Pratama, Arnia Putri Priantini, Tania Putri Nurul Amalia Putri, Danika Nurranalya Putri, Yulia Mariana Tesa Ayudia Rahayu, Dyah Utami Cahyaning Rahma Widya Rahma Widya RAHMAT WIBOWO Rahmawati, Isnaini Ralentri Pertiwi Richter, Manfred Ridwan, Ridwan Rika Tri Yunarti Riri Andriyanti Riwandi Sihombing Riwandi Sihombing Riwandi Sihombing Riwandi Sihombing Riwandi Sihombing, Riwandi Robert, Didier Russell Francis Howe Russell Francis Howe Russell Francis Howe Russell Francis Howe, Russell Francis Sanjaya, Afiten Rahmin Saragi, Indah Revita Sariman Sariman Savitri Octaviani Siti Zahrotul Luthfiyah SJATHA, FITHRIYAH Supriyono Supriyono Tengku Riza Zarzani N Tesla, Yudistira Uwin Sofyani Widhyasmaramurti Widya, Rahma Yunarti, Rika Tri