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COMPOSITE OF CHITOSAN VANILIN / SULFONATED POLYSTYRENE AS POLYMER ELECTROLYTE MEMBRANES : CATIONIC EXCHANGE CAPACITY, SWELLING DEGREE AND THERMAL PROPERTIES Pramono, Edi; Purnawan, Candra; Hidayat, Yuniawan; Wulansari, Jati; Wahyuningsih, Sayekti
Alchemy Jurnal Penelitian Kimia Vol 10, No 2 (2014)
Publisher : Alchemy Jurnal Penelitian Kimia

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Abstract

Research on the preparation and characterization of sulfonated polystyrene (PST) /chitosan vanillin (KV) composite as electrolyte membranes has been conducted in order to investigate the effect of PST and KV composition  to its chemical and physical properties. Polystyrene was modified by sulfonation reaction to produces PST, meanwhile chitosan was modified by schift base reaction to produces KV. The composite membranes were prepared by casting method and were characterized in order to identify the functional groups contained in the composite, the cation exchange capacity (CEC), the Swelling Degree (SD), the thermal properties and the morphology. The peak of imine vibration in the FTIR spectrum indicates that the chitosan vanilin was succesfully synthesized. Meanwhile, the peak of sulfonate vibration indicates the product of sulfonation on polystyrene. The result of CEC analysis shows that the addition of sulfonate groups on polystyrene and the addition of phenolic groups on chitosan increase the CEC value. The increasing of PST and KV concentration in membrane enhance the CEC value. However, the increasing of PST concentration in membrane composition even decrease the Swelling Degree of membranes. Meanwhile, the increasing of KV concentration increase the swelling degree of membranes. Thermal analysis shows that the thermal decomposition of membranes occurs in three stages i.e. the dehydration of water molecules, the degradation of the subtituen groups and the plasticizer and the degradation of the back bone of chitosan and polystyrene.
EFFECT OF CONCENTRATION METAL PRECURSOR Co AND Mo ON CHARACTER OF CoMo / USY CATALYST Nugrahaningtyas, Khoirina Dwi; Hidayat, Yuniawan; Saputri, Tiara Diah
Alchemy Jurnal Penelitian Kimia Vol 10, No 1 (2014)
Publisher : Alchemy Jurnal Penelitian Kimia

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Abstract

The preparation and characterization of bimetallic catalysts using impregnation method with a variation of concentration of precursor sequence Co and Mo metal  obtained  catalyst K 1 [Co (0.018 M) - Mo (0.037 M)/USY]. K 2 [Co (0.026 M) - Mo (0.055 M)/USY], K 3 [Co (0.035 M) - Mo (0.074 M)/USY], K 4 [Co (0.05 M) - Mo (0.11 M )/USY] and K 5 [Co (0.107 M) - Mo (0.22 M)/USY].Character of the catalyst in terms  of crystallinity was analyzed by XRD. The result shows that there is no cristalinity damage of USY after impregnation but the amorphous cristalin structure was obtained.  Amount of metal content was analyzed by XRF and the catalyst morphology by SEM-EDS. The result shows that the higher the concentration of Co and Mo so that find the higher content of metal in catalyst of the prepared catalyst increase. K 4 shows the best characteristic of catalysts prepared in this research. Analysis of K 4 is proving that Co and Mo are presented in catalyst
PENGARUH LAJU ALIR HIDRGEN DAN WAKTU REAKSI TERHADAP LAJU REAKSI, SELEKTIFITAS DAN AKTIVITAS KATALIS Pt-Pd /ZAA PADA HIDRODEOKSIGENASI TETRAHIDROFURAN Hidayat, Yuniawan; ., Triyono; Trisunaryati, Wega
Alchemy Jurnal Penelitian Kimia Vol 4, No 2 (2005)
Publisher : Alchemy Jurnal Penelitian Kimia

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Telah dilakukan penelitian tentang pengaruh laju alir hidrogen dan waktu reaksi terhadap aktivitas katalis Pt-Pd/zeolit alam aktiv (ZAA) pada reaksi hidrodeoksigenasi (HDO) terahidrofuran (THF). Katalis Pt-Pd/ZAA dibuat dengan metoda impregnasi basah. Uji katalis dilakukan dengan menggunakan reaktor sistem alir pada temperatur 350oC selama 1,5 jam dengan berat katalis 1 gram untuk setiap perlakuan.Untuk memperoleh pengaruh laju alir hidrogen terhadap aktivitas katalis, laju alir gas hidrogen divariasikan pada 5, 10, 20 dan 40 mL.menit-1 . Sedangkan untuk mengetahui pengaruh waktu reaksi, maka pada setiap variasi laju alir tersebut, produk yang telah terkondensasi diambil setiap 15 menit. Produk yang terbentuk kemudian dianalisis dengan Kromatografi Gas (GC) dan Kromatografi Gas-Spektrometer Massa (GC-MS).Hasil analisis terhadap produk reaksi dengan menggunakan GC-MS  menunjukkan bahwa THF terdeoksigenasi menjadi senyawa C3 (propena) dan C4 (butena dan butadiena). Produk C3 terbentuk melalui dua jalur rekasi, pemutusan ikatan CO langsung dan melalui tahap internediet butanal. Penambahn laju alir hidrogen menyebabkan laju reaksi semakin bertambah dan reaksi menjadi selektif terhadap pembentukan produk C4 maupun selektif terhadap jalur reaksi pembentukan produk C3. Penambahan laju alir hidrogen juga efektif mengurangi laju deaktivasi katalis dalam reaksi HDO THF. Jumlah konversi total maksimum diperoleh pada laju alir hidrogen 10 mL.menit-1 .
HDO REACTION OF THF USING Pt/-AL2O3 CATALYST ENRICHED BY ALUMINA : EFFECT OF TEMPERATURE TO PRODUCT DISTRIBUTION, RATE OF REACTION AND DEACTIVATON OF CATALYST Hidayat, Yuniawan; Nurcahyo, IF.; Sofiana, Ana; Saputro, Arifin Dwi
Alchemy Jurnal Penelitian Kimia Vol 10, No 1 (2014)
Publisher : Alchemy Jurnal Penelitian Kimia

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Abstract

Effect of temperature variation to product distribution, rate and deactivation of catalyst of tetrahydrifuran hydrodeoxygenation have been conducted using Pt/-Al2O3 with aluminum enrichmen. Reaction was conducted by flow system. Product of reaction were analyzed as propane (C3) and buthene derivate (C4). At 350 oC, reaction product and rate constant were optimum. At higher temperature, product distribution was shift from C4 to C3. Lowering pore size catalyst, surface area and acidity of catalyst were responsible to catalyst deactivation. Deactivation process was follow exponential regression.
KAJIAN KESAHIHAN PERSAMAAN ESPENSON (1995) UNTUK REAKSI ENZIMATIS DAN YANG MIRIP Patiha, Patiha; Mudjijono, Mudjijono; Hidayat, Yuniawan; Pramono, Edy
Indonesian Journal of Chemical Science Vol 3 No 2 (2014)
Publisher : Indonesian Journal of Chemical Science

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Telah dilakukan kajian tentang kesahihan persamaan Espenson (1995). Pertama secara teoritis atas paradigma yang digunakan dan kemudian dari hasilpenerapannya pada penentuan tetapan Michaelis-Menten dari reaksi brominasi aseton.  Dikatakan sahih jika, secara teoritis konsisten dengan konsep dasar kinetika kimia dan reaksi enzimatisdan memberikan harga tetapan Michaelis-Menten yang pasti. Ditemukan bahwa persamaan tersebut tidak/kurang sahih.
STUDI KINETIKA REAKSI HIDROGEN PEROKSIDA DENGAN IODIDA PADA SUASANA ASAM R. Hakim, Arif; Patiha, Patiha; Hidayat, Yuniawan
Indonesian Journal of Chemical Science Vol 3 No 2 (2014)
Publisher : Indonesian Journal of Chemical Science

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Studi kinetika reaksi hidrogen peroksida dengan iodida pada suasana asam telah dilakukan. Tujuan penelitian ini adalah membuktikan apakah hukum laju reaksi merupakan penjumlahan, pecahan ataugabungan keduanya. Desain percobaan yang digunakanadalah metode isolasi dengan H+ dan I- dibuat berlebih terhadap H2O2.Hasil percobaan variasi konsentrasi H+menunjukan reaksi dapat memenuhi hukum laju dalam bentuk penjumlahan. Pada percobaan variasi konsentrasi H2O2, H2O2 teramati dapat berorder 0 atau 1 bergantung pada konsentrasinya sesuai dengan yang diperkirakan dari hukum laju pecahannya. Berdasarkan hasil percobaan, reaksi disimpulkan memiliki hukum laju gabungan keduanya yang lebih lanjut terbukti berdasarkan nilai konstanta laju perhitungan.
HDO Reaction of THF Using Pt/γ-Al2O3 Catalyst Enriched by Alumina: Effect of Temperature to Product Distribution, Rate of Reaction and Deactivation of Catalyst Hidayat, Yuniawan; Nurcahyo, Idul Fitri; Sofiana, Ana; Saputro, Arifin Dwi
ALCHEMY Jurnal Penelitian Kimia Vol 10, No 1 (2014): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.10.1.5.94-104

Abstract

Effect of temperature variation to product distribution, rate and deactivation of catalyst of tetrahydrifuran hydrodeoxygenation have been conducted using Pt/gAl2O3 with aluminum enrichmen. Reaction was conducted by flow system. Product of reaction were analyzed as propane (C3) and buthene derivate (C4). At 350ºC, reaction product and rate constant were optimum. At higher temperature, product distribution was shift from C4 to C3. Lowering pore size catalyst, surface area and acidity of catalyst were responsible to catalyst deactivation. Deactivation process was follow exponential regression.
Effect Of Concentration Metal Precursor Co And Mo On Character Of CoMo / USY Catalyst Nugrahaningtyas, Khoirina Dwi; Hidayat, Yuniawan; Saputri, Tiara Diah
ALCHEMY Jurnal Penelitian Kimia Vol 10, No 1 (2014): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.10.1.9.40-48

Abstract

The preparation and characterization of bimetallic catalysts using impregnation method with a variation of concentration of precursor sequence Co and Mo metal  obtained  catalyst K 1 [Co (0.018 M) - Mo (0.037 M)/USY]. K 2 [Co (0.026 M) - Mo (0.055 M)/USY], K 3 [Co (0.035 M) - Mo (0.074 M)/USY], K 4 [Co (0.05 M) - Mo (0.11 M )/USY] and K 5 [Co (0.107 M) - Mo (0.22 M)/USY].Character of the catalyst in terms  of crystallinity was analyzed by XRD. The result shows that there is no cristalinity damage of USY after impregnation but the amorphous cristalin structure was obtained.  Amount of metal content was analyzed by XRF and the catalyst morphology by SEM-EDS. The result shows that the higher the concentration of Co and Mo so that find the higher content of metal in catalyst of the prepared catalyst increase. K 4 shows the best characteristic of catalysts prepared in this research. Analysis of K 4 is proving that Co and Mo are presented in catalyst
Activated Carbon Addition Methods on the Pre-impregnation Process of Co-Mo in Y-Zeolite Ultra Stable: A Properties Exploration and Enhancement of Metals Loaded Hidayat, Yuniawan; Nugrahaningtyas, Khoirina Dwi; Hendrastuti, Priska Julia
Jurnal Riset Kimia Vol 12, No 2 (2021): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i2.384

Abstract

The amount of loaded Co-Mo metal on the Y-Zeolite Ultra Stable (USY) was increased by the addition of activated carbon in the pre-impregnation process. USY modification was done by adding activated carbon to USY as much as 10 wt%. The process of adding activated carbon is carried out by three methods, i.e., grinding with sucrose binder (ACU1), without sucrose (ACU2), and conducting by ball milling (ACU3). Wet impregnation method was employed to disperse the Co and Mo, sequentially. Composites were characterized using Fourier Transform Infrared (FTIR), X-ray diffraction (XRD), and surface area analyzer (SAA). Metal dispersions were observed by X-ray fluorescence (XRF). The FTIR suggests an interaction between USY and activated car-bon, while the XRD result indicated the none structural transformation of USY zeolite. The SAA analysis showed an increased total pore radius with the activated carbon addition. The XRF confirmed the increasing of total metals dispersion of 6.25% (ACU1); 5.48%(ACU2); 5.18% (ACU3); compare to USY origin with 3.28% metals loaded.
The Role of The Ni/HZSM-5 Ratio on The Anisole Hydrodeoxygenation Reaction Nugrahaningtyas, Khoirina Dwi; Nurcahyo, I F; Hidayat, Yuniawan; Rahmawati, Fitria; Fadlulloh, Zaki; Heraldy, Eddy; Qurrotul'aini, Nisriina 'Abidah
Molekul Vol 19 No 2 (2024)
Publisher : Universitas Jenderal Soedirman

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20884/1.jm.2024.19.2.11105

Abstract

ABSTRACT. Bio-oil is a renewable energy source with high oxygen levels, and anisole is a chemical widely employed in research to represent it. Catalytic hydrodeoxygenation (HDO) reduces the oxygen content. A catalyst known as nickel-modified HZSM-5 has shown promising results for HDO. Meanwhile, catalyst efficiency depends on the Ni/HZSM-5 ratio. So, this study aims to determine how the Ni/HZSM-5 ratio influences the catalyst's properties, activity, and selectivity in anisole HDO. The Ni/HZSM-5 catalyst was made using the wet impregnation method with various ratios of Ni/HZSM-5. The catalysts were analyzed for their morphology using scanning electron microscopy-energy-dispersive X-ray (SEM-EDX). The diffraction patterns were studied using X-ray diffraction (XRD). Surface area and porosity were determined through gas sorption analysis (GSA). Then, the acidity strength was evaluated via temperature-programmed ammonia desorption (NH3-TPD). The characterization results show Ni was successfully impregnated and distributed evenly in HZSM-5 without changing the primary structure. Adding Ni metal to HZSM-5 increases the surface area of the catalyst but reduces its acid strength. The catalytic performance of the catalysts was then evaluated in a flow reactor at 400 °C, using 15 mL/min H2 gas. The liquid products of the reaction were analyzed using gas chromatography-mass spectroscopy (GC-MS). The results of the catalytic performance show that Ni4.5/HZSM-5 has the highest catalytic activity in anisole conversion. At the same time, Ni6.4/HZSM-5 shows the highest selectivity towards benzene-toluene-xylene (BTX). Keywords: Hydrodeoxygenation, nickel, anisole, heterogeneous catalyst, acidity.