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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

Author-ID : 1133084

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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PHOTOCURRENT ENHANCEMENT OF CdS QUANTUM DOT SENSITIZED TiO2 ELECTRODE IN THE PRESENCE OF GOLD NANO PARTICLES Supriyono Supriyono; Hedi Surahman; Yuni Krisyuningsih Krisnandi; Jarnuzi Gunlazuardi
Jurnal Sains Materi Indonesia Vol 16, No 3: APRIL 2015
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

PHOTOCURRENT ENHANCEMENT OF CdS QUANTUM DOT SENSITIZED TiO2 ELECTRODE IN THE PRESENCE OF GOLD NANO PARTICLES. Photo current enhancement of CdS Quantum Dot (CdS-QD) sensitized TiO2 electrode in the presence of gold nano particles had been investigated. CdS quantum dots were prepared by successive ionic layer adsorption and reaction (SILAR) method, in which solution containing Cd(CH3COO)2 and Na2S were used as a precursor. Where as, gold nano particles was synthesized using solution containing HAuCl4 as a precursor, NaBH4 as a reducing agent and polyvinyl pyrrolydone (PVP) as a stabilizer. The film of CdS quantum dots and Au nano particles were characterized by UV-Vis spectrophotometer, Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), and electro chemical working station. Photo electrochemical study revealed that CdS-sensitized TiO2 electrode with gold nanoparticles have been able to increase photocurrent of 54 A/cm2 to 68 A/cm2, so the photocurrent enhancement of approximately 25% was observed. This observation indicates that the gold nanoparticles is potentially applicable to enhance photocurrent in a CdS-QD sensitized TiO2 electrode, which may lead to the development of more efficient solar cell.

Effect of Physicochemical Properties of Co and Mo Modified Natural Sourced Hierarchical ZSM-5 Zeolite Catalysts on Vanillin and Phenol Production from Diphenyl Ether Anita Nur Ramadhani; Iman Abdullah; Yuni Krisyuningsih Krisnandi
Bulletin of Chemical Reaction Engineering & Catalysis 2022: BCREC Volume 17 Issue 1 Year 2022 (March 2022)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.17.1.13372.225-239

The conversion of lignocellulose biomass to value-added chemicals is challenging. In this paper, the conversion process of diphenyl ether (DPE) as a model lignin compound to phenol and vanillin compounds involved a bifunctional catalyst in reaching the simultaneous one-pot reaction in mild conditions with a high yield product. The catalysts used in this conversion are hierarchical ZSM-5 zeolites and their cobalt oxide and molybdenum oxide impregnated derivate. The ZSM-5 zeolites were synthesized using alternative precursors from natural resources, i.e., Indonesian natural zeolite and kaolin. The physicochemical properties of the catalysts were determined with various characterization methods, such as: X-ray Diffraction (XRD), Fourier Transform Infra Red (FT-IR), Scanning Electron Microscope - Energy Dispersive X-ray (SEM-EDX), X-ray Fluorescence (XRF), Surface Area Analyzer (SAA), and NH3-Temperature Programmed Desorption (NH3-TPD). The catalytic activity on conversion of DPE substrates showed that the MoOx/HZSM-5 produced the highest %yield for phenol and vanillin products; 31.96% at 250 °C and 7.63% at 200 °C, respectively. The correlation study between the physicochemical properties and the catalytic activity shows that the dominance of weak acid (>40%) and mesoporosity contribution (pore size of ~ 9 nm) play roles in giving the best catalytic activity at low temperatures. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Nickel-phenanthroline Complex Supported on Mesoporous Carbon as a Catalyst for Carboxylation under CO2 Atmosphere Iman Abdullah; Riri Andriyanti; Dita Arifa Nurani; Yuni Krisyuningsih Krisnandi
Bulletin of Chemical Reaction Engineering & Catalysis 2021: BCREC Volume 16 Issue 1 Year 2021 (March 2021)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.16.1.9733.111-119

Carbon dioxide is a highly potential renewable C1 source for synthesis of fine chemicals. Utilization of CO2 in carboxylation reactions requires catalysts, such as: nickel complex for CO2 activation. However, the use of homogeneous catalysts in the reaction is still less efficient due to the difficulty of separating the product and catalyst from reaction mixture. Therefore, it is necessary to heterogenize the nickel complex in a solid support such as mesoporous carbon. In this report, mesoporous carbon (MC) prepared from phloroglucinol and formaldehyde through soft template method was used as a solid support for Ni-phenanthroline complex (Ni-phen). The catalyst was characterized by Fourier Transform Infra Red (FT-IR), X-Ray Diffraction (XRD), Scanning Electron Microscope - Energy Dispersive X-Ray (SEM-EDX), and Surface Area Analyzer (SAA). The result of SAA characterization showed that the pore diameter of MC was 6.7 nm and Ni-phen/MC was 5.1 nm which indicates that the materials have meso-size pores. Ni-phen/MC material was then used as a heterogeneous catalyst in the carboxylation reaction of phenylacetylene under an ambient CO2 pressure. The reactions were carried out in several variations of conditions such as temperature, time and catalyst types. Based on the results of the reaction, the best conditions were obtained at 25 °C for 8 h of reaction time using Ni-phen/MC catalyst. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Synthesis and Characterization of Mesoporous Carbon Supported Ni-Ga Catalyst for Low-Pressure CO2 Hydrogenation Uwin Sofyani; Yuni Krisyuningsih Krisnandi; Iman Abdullah
Bulletin of Chemical Reaction Engineering & Catalysis 2022: BCREC Volume 17 Issue 2 Year 2022 (June 2022)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.17.2.13377.278-285

In this study, the atmospheric-pressure hydrogenation of CO2 was carried over bimetallic Ni-Ga catalyst supported on mesoporous carbon (MC). MC was successfully prepared using the soft-template method as proven by Fourier Transform Infra Red (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy - Energy Dispersive X-Ray Spectroscopy (SEM-EDS), Brunauer–Emmett–Teller Surface Area Analyzer (BET SAA), and Transmission Electron Microscopy (TEM) characterizations. The Ni-Ga/MC catalyst was synthesized using the impregnation method, and based on the XRD characterization, the formation of bimetallic Ni-Ga on the MC support is confirmed. The EDS mapping image shows the uniform distribution of the bimetallic Ni-Ga on the MC surface, especially for the Ni5Ga3/MC and NiGa3/MC catalysts. Moreover, the TEM images show an excellent pore size distribution. The formation of Ni-Ga alloy was identified as an active site in the CO2 hydrogenation. Ni5Ga3/MC catalyst exhibited a 10.80% conversion of CO2 with 588 μmol/g formaldehyde at 1 atm, 200 °C, and H2/CO2 ratio of 3/1. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Penggunaan Teknologi dalam Pelatihan Pembuatan Sabun sebagai Upaya Pemberdayaan Santri Pesantren Darussalam - Sumenep di Masa Pandemi Covid-19 Widhyasmaramurti Widhyasmaramurti; Khanifah Khanifah; Yuni Krisyuningsih Krisnandi
Jurnal Abdidas Vol. 2 No. 1 (2021): February, Pages 1-160
Publisher : Universitas Pahlawan Tuanku Tambusai

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31004/abdidas.v2i1.232

Pandemi Covid-19 yang melanda seluruh dunia berimbas ke berbagai ranah kehidupan masyarakat. Efek Covid-19 juga dirasakan oleh para santri Pesantren Darussalam Sumenep. Di masa pandemi ini, para santri dihadapkan pada pilihan kembali ke rumah atas desakan ekonomi, atau tetap bertahan di pesantren. Santri yang bertahan di pesantren perlu mematuhi protokol kesehatan yaitu mencuci tangan, memakai masker dan menjaga jarak. Hal ini menyebabkan kebutuhan sabun dalam lingkungan pesantren meningkat. Maka pelatihan pembuatan sabun dilakukan dengan tujuan sebagai upaya pemberdayaan masyarakat untuk mendukung pencegahan Pandemi Covid-19 dalam lingkup pesantren, namun tetap memiliki nilai ekonomi di saat yang bersamaan. Adanya Pembatasan Sosial Berskala Besar (PSBB) di daerah-daerah di Indonesia tidak membuat pelatihan pembuatan sabun terhenti karena teknologi tepat guna digunakan sebagai alternatif pelatihan pembuatan sabun. Pelatihan secara sinkronus dengan menggunakan platform Zoom, video demonstrasi pembuatan sabun yang terakses melalui media daring seperti YouTube, serta pendampingan kontinu oleh koordinator lapangan menjadi alternatif pelatihan di masa pandemi ini. Kurang stabilnya akses jaringan internet menjadi tantangan yang ditindaklanjuti melalui forum diskusi (chat) menggunakan WhatsApp. Proses evaluasi menggunakan Focus Group Discussion (FGD) dan Google Form menjadi sarana melihat indikator keberhasilan. Hasil pengabdian masyarakat ini ada dua, yaitu: 1) tertransfernya pengetahuan pembuatan sabun melalui teknologi tepat guna, 2) terbentuknya komunitas santri yang mampu memproduksi sabun. Walaupun produksi sabun masih bersifat untuk konsumsi internal pesantren, namun santri Pesantren Darussalam diharapkan mampu membangun jaringan penjualan sabun sebagai upaya peningkatan ekonomi mereka. Pemberdayaan masyarakat ini juga diharapkan dapat membentuk komunitas santri yang mampu mendukung pemerintah dalam upaya mencegah Covid-19.

Direct Synthesis of Methanol by Partial Oxidation of Methane with Oxygen over Cobalt Modified Mesoporous H-ZSM-5 Catalyst Yuni Krisyuningsih Krisnandi; Bayu Adi Samodro; Riwandi Sihombing; Russell Francis Howe
Indonesian Journal of Chemistry Vol 15, No 3 (2015)
Publisher : Universitas Gadjah Mada

Partial oxidation of methane over mesoporous catalyst cobalt modified H-ZSM-5 has been carried out. Mesoporous Na-ZSM-5 (Si/Al = 35.4) was successfully synthesized using double template method which has high surface area (450 m2/g) and average pore diameter distribution of 1.9 nm. The as-synthesized Na-ZSM-5 was converted to H-ZSM-5 through multi-exchange treatment with ammonium ion solution, causing decreased crystallinity and surface area, but increased porous diameter, due to dealumination during treatment process. Moreover, H-ZSM-5 was loaded with cobalt (Co = 2.5% w) by the incipient impregnation method and calcined at 550 °C. Partial oxidation of methane was performed in the batch reactor with 0.75 bar methane and 2 bar of nitrogen (with impurities of 0.5% oxygen) as the input at various reaction time (30, 60 and 120 min). The reaction results show that cobalt species in catalyst has an important role, because H-ZSM-5 cannot produce methanol in partial oxidation of methane. The presence of molecular oxygen increased the percentage of methanol yield. The reaction is time-dependent with the highest methanol yield (79%) was acquired using Co/H-ZSM-5 catalyst for 60 min.

Hierarchical MnOx/ZSM-5 as Heterogeneous Catalysts in Conversion of Delignified Rice Husk to Levulinic Acid Yuni Krisyuningsih Krisnandi; Dita Arifa Nurani; Anastasia Agnes; Ralentri Pertiwi; Noer Fadlina Antra; Alika Rizki Anggraeni; Anya Prilla Azaria; Russell Francis Howe
Indonesian Journal of Chemistry Vol 19, No 1 (2019)
Publisher : Universitas Gadjah Mada

Hierarchical ZSM-5 zeolite was synthesized using a double template method using TPAOH and PDDA as templates, while microporous ZSM-5 was also prepared using only TPAOH as a template. The syntheses then were followed by impregnation with Mn(II) c.a. 2 wt.% and calcination at 550 °C to obtain MnOx/ZSM-5 zeolite catalysts. Extensive characterization of the zeolite catalysts was performed using XRD, SEM, AAS, EDX, FTIR and BET measurement. The characterization showed that hierarchical or mainly mesoporous ZSM-5 was successfully synthesized, having added features compared to the microporous counterpart. The catalysts then were used in conversion reaction of delignified rice husk to levulinic acid, a platform chemical. As a comparison, a certain amount of MnCl2.4H2O was used as a homogeneous catalyst in a similar reaction. The product of the reaction was separated and analyzed with HPLC. It showed that 8 h was the optimum condition for the conversion, with hierarchical MnOx/hi_ZSM-5 catalyst gave the highest amount of levulinic acid (%Y of 15.83%), followed by microporous MnOx/mi_ZSM-5 (%Y of 10%). The % yield of levulinic acid using homogeneous Mn(II) catalyst (%Y of 8.86%) gave more charcoal as a product. Meanwhile, the stability of the zeolite catalysts after the reaction has also been investigated, mainly by analyzing the FTIR spectra and EDX data of the used catalysts after separated and calcined at 550 °C. From the analysis, some of the silica and alumina are leached from the framework, as well as the manganese oxide due to acidic condition at the beginning of the reaction. Nevertheless, it can be concluded that the conversion took place as the interaction between the cellulose and either MnOx in zeolites or Mn2+ ions in the solution, with the support of porous ZSM-5 framework. Hierarchical system somehow assists the ZSM-5 structure stays intact.

Synthesis and Characterization of Copper Impregnated Mesoporous Carbon as Heterogeneous Catalyst for Phenylacetylene Carboxylation with Carbon Dioxide Putri Nurul Amalia; Iman Abdullah; Dyah Utami Cahyaning Rahayu; Yuni Krisyuningsih Krisnandi
Indonesian Journal of Chemistry Vol 21, No 1 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.52778

Carbon dioxide (CO2) is a compound that can potentially be used as a carbon source in the synthesis of fine chemicals. However, the utilization of CO2 is still constrained due to its inert and stable nature. Therefore, the presence of a catalyst is needed in CO2 conversion. This study aims to synthesize copper impregnated mesoporous carbon (Cu/MC) as a catalyst for phenylacetylene carboxylation reaction with CO2 to produce phenylpropiolic acid. The synthesis of mesoporous carbon was performed via the soft template method. The as-synthesized Cu/MC material was characterized by FTIR, SAA, XRD, and SEM-EDX. BET surface area analysis of mesoporous carbon showed that the material has a high surface area of 405.8 m2/g with an average pore diameter of 7.2 nm. XRD pattern of Cu/MC indicates that Cu has been successfully impregnated in the form of Cu(0) and Cu(I). Phenylacetylene carboxylation reaction with CO2 was carried out by varying reaction temperatures (25, 50, and 75 °C), amount of catalyst (28.6, 57.2, and 85.8 mg), type of base (Cs2CO3, K2CO3, and Na2CO3), and variation of support. The reaction mixtures were analyzed by HPLC and showed that the highest phenylacetylene conversion of 41% was obtained for the reaction at 75 °C using Cs2CO3 as a base.

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
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

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
Publisher : UI Scholars Hub

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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.

Co-Authors Adam, Martin Adel Fisli Ahmed, Sabeel Alika Rizki Anggraeni 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 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 Noer Fadlina Antra Novia Arinda Pradisty Nurani, Dita Arifa Nurhalimah, Dede Paputungan, Zulkarnaen Pradisty, Novia Arinda Priantini, Tania Putri Nurul Amalia Putri, Danika Nurranalya Putri, Yulia Mariana Tesa Ayudia Rahayu, Dyah Utami Cahyaning Rahma Widya Rahma Widya Rahmawati, Isnaini Ralentri Pertiwi Richter, Manfred Ridwan, Ridwan Rika Tri Yunarti Riri Andriyanti Riwandi Sihombing Riwandi Sihombing Riwandi Sihombing Riwandi Sihombing Riwandi Sihombing, Riwandi Riyanto, Hanzhola Gusman 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, Widhyasmaramurti Widya, Rahma Yunarti, Rika Tri

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