Articles

PREPARASI DAN KARAKTERISASI KOMPOSIT KROMIUM OKSIDA-MONTMORILLONIT Sutha Negara, I M.; Wijaya, Karna; Sugiharto, Eko
Journal of Chemistry Vol. 2, No. 2 Juli 2008
Publisher : Journal of Chemistry

Show Abstract | Original Source | Check in Google Scholar

Abstract

The objectives of this research were to prepare montmorillonite and of chromium oxide-montmorillonitecomposite by intercalation of oxide of chrom into the silicates interlayer of montmorillonite, and to characterizesome of their physical and chemical properties. The characterization indicated that the basal spacing d001 wasincreased from 14,11 in montmorillonit to 15,55 in chromium oxide-montmorillonite; specific surface area wasincreased from 69,71 m2/g to 240,40 m2/g; total pore volume was also increased from 0,05 mL/g to 0,128 mL/g; andchrom content also increased from 0,007% (w/w) to 17,16 % (w/w).
STUDI PENDAHULUAN PEMANFAATAN LIMBAH DESALINASI UNTUK PEMBUATAN Mg/Al HYDROTALCITE-LIKE SEBAGAI ADSORBEN METHYL ORANGE Heraldy, Eddy; Prasasti, Dian; Wijaya, Karna; Santosa, Sri Juari; Triyono, Triyono
Bumi Lestari Journal of Environment Vol 12, No 1
Publisher : Udayana University

Show Abstract | Original Source | Check in Google Scholar

Abstract

The utilization of industrial wastewater into a versatile material that has been the focus of research for economics reasons, environmental and technical. One of the proposed industrial wastewater for a new useful material is wastewater from the desalination process which is also known as brine water. The magnesium content in brine water is able to used as a source of magnesium for the synthesis of Mg/Al hydrotalcite-like compound (Mg/Al HTlc). Mg/Al HTlc are widely investigated for their potential applications in research and industrial processes as adsorbents, catalysts and /or catalyst precursors and pharmaceutical industry excipients. As adsorbents, Mg/Al HTlc are receiving greater interests in the environmental community due to their high adsorption capacity. However, before using natural brine water, has conducted a preliminary study the synthesis of Mg/Al HTlc by using artificial brine water as a model of desalination wastewater. The objective of this research is to synthesis of Mg/Al HTlc from artificial brine water and its ability tested as a methyl orange (MO) adsorbents. The research initiated with the synthesis of Mg/Al HTlc from artificial brine water. Characterization of the Mg/Al HTlc synthesized was confirmed through X-ray Diffraction and FT-IR Spectroscopy. The determination of optimum acidity, adsorption rate, and energy and capacity adsorption were studied. The result showed that pH 3 was the optimum acidity for the adsorption of MO on Mg/Al HTlc. MO was adsorbed at first order adsorption rate of 7.30 × 10-4 s-1 on the Mg/Al HTlc, the adsorption capacity and adsorption energy were 4.36 × 10-5 mol g-1 and 27.54 kJ mol-1, respectively. From the preparatory process and the synthesis of Mg/Al HTlc by using artificial brine water to provide the information that the byproduct of desalination processes (brine water) which are believed to be used for the synthesis of Mg / Al HTlc.
HUBUNGAN KUANTITATIF STRUKTUR ELEKTRONIK DAN AKTIVITAS ANTITUMOR SENYAWA TURUNAN AMINO PIRIMIDO ISOKUINOLIN KUINON DENGAN PENDEKATAN REGRESI KOMPONEN UTAMA Saputra, Andrian; Wijaya, Karna; Tahir, Iqmal
CHEMISTRY PROGRESS Vol 6, No 1 (2013)
Publisher : Sam Ratulangi University

Show Abstract | Original Source | Check in Google Scholar | Full PDF (1024.725 KB)

Abstract

Tujuan penelitian ini yaitu menganalisis Hubungan Kuantitatif Struktur Aktivitas (HKSA) turunan amino pirimidoisokuinolin kuinon yang berkhasiat sebagai antitumor telah dilakukan dengan menggunakan pendekatan regresikomponen utama. Data aktivitas biologis yang digunakan pada penelitian ini merupakan aktivitas senyawamelawan sel tumor AGS (Human Gastric Adenocarcinoma Cell Line) dalam ukuran log IC 50 . Sebagai deskriptordigunakan muatan atom bersih bersih (q) pada kerangka struktur senyawa dari hasil optimasi geometrimenggunakan perhitungan mekanika kuantum semiempirik AM1. Analisis komponen utama dilakukan sebelum proses regresi untuk mendapatkan variabel laten yang merupakan hasil transformasi data deskriptor muatanatom bersih (q). Dengan pendekatan regresi komponen utama diperoleh keterkaitan erat antara log IC 50 dan q yang direpresentasikan dengan persamaan HKSA berikut :log IC 50 = 0,671 - 0,041.x 1 + 0,232.x 2 + 0,270.x 3 - 0,087.x 4 + 0,105.x 5dengan, n = 27, r = 0,762, SE = 0,362, F hitung /F tabel = 2,168.Quantitative Structure Activity Relationship (QSAR) analysis of amino-pyrimido-isoquinolin-quinone analoguesas antitumor compound has been done using principal component regression approaches. Biological activitydata that used in this research were the activity against tumor cell AGS (Human Gastric Adenocarcinoma CellLine) as log IC 50 values. Atomic net charges (q) in the skeleton of the compound have been selected asdescriptors and all data were resulted by geometry optimization using AM1 semiempirical quantum mechanicscalculations. Principle component analysis has been performed before regression process to produce latentvariables by transformation of the descriptors. Based on principle component regression approaches, there isa selected quantitative relationship between log IC 50 to the descriptors that was shown by QSAR equation below:log IC 50 = 0.671 – 0.041.x 1 + 0.232.x 2 + 0.270.x 3 – 0.087.x 4 + 0.105.x 5with, n = 27, r = 0.762, SE = 0.362, F calc. /F table = 2.168.
ANALYSIS OF HYDROGEN ADSORPTION AND DIFFUSION ON Mg(0001) SURFACE: AN AB INITIO DFT STUDY Sutapa, I Wayan; Amunanto, Ria; Wijaya, Karna
Jurnal Sains dan Terapan Kimia Vol 4, No 1 (2010)
Publisher : Jurnal Sains dan Terapan Kimia

Show Abstract | Original Source | Check in Google Scholar

Abstract

Ab initio density functional theory (DFT) calculations are performed to study the adsorption ofH2 molecules on a Mg(0001) surface. First, the adsorption energy was investigated. In thecalculation of the adsorption process of molecular hydrogen, observation showed a physicaladsorption of molecular hydrogen rather than chemisorptions.The diffusion process of atomichydrogen on Mg (0001) was also presented. Finally, we are comparing all of our calculationwith results from previous experiments.Keyword: DFT, Adsorption, Diffusion, Mg(0001), H2
Optimisasi Rasio Diazinon/Asam Metakrilat Secara Teoritik Berdasarkan Metoda Semiempirik Am1 Untuk Sintesis Polimer Tercetak Molekul Saputra, Andrian; Wijaya, Karna; Ahmad, Mohd Noor; Tahir, Iqmal
Jurnal Sains dan Terapan Kimia Vol 7, No 2 (2013)
Publisher : Jurnal Sains dan Terapan Kimia

Show Abstract | Original Source | Check in Google Scholar

Abstract

Rasio optimum diazinon/asam metakrilat pada desain polimer tercetak molekul untuk aplikasi sensor diazinon berbasis quartz crystal microbalance telah ditentukan secara teoritik menggunakan perhitungan mekanika kuantum semiempirik AM1. Kajian ditentukan berdasarkan pemodelan molekul yang mempelajari interaksi non kovalen antara diazinon sebagai templat dan asam metakrilat sebagai monomer fungsional. Analisis dilakukan untuk mencari kestabilan komplek yang terbentuk dengan berdasarkan parameter energi interaksi antara diazinon dan asam metakrilat yang dilakukan dengan menggunakan perangkat lunak Hyperchem 7.5.  Hasil penelitian menunjukkan pembentukan komplek stabil terjadi dengan melibatkan  ikatan hidrogen.  Untuk kompleks dengan energi interaksi optimum diperoleh dari komplek diazinon/asam metakrilat dengan rasio 1:3, yang kemudian direkomendasikan sebagai rasio mol optimum pada sintesis polimer tercetak diazinon.   Kata kunci : diazinon, asam metakrilat, semiempirik AM1, polimer tercetak molekul, Quartz Crystal Microbalance
Penggunaan Metode Semiempirik AM1 Untuk Pemilihan Monomer Fungsional Efektif Pada Prasintesis Polimer Tercetak Diazinon Saputra, Andrian; Wijaya, Karna; Ahmad, Mohd Noor; Tahir, Iqmal
VALENSI Vol 3, No 1 (2013): Jurnal Kimia Valensi Volume 3//No.1//Mei 2013
Publisher : Program Studi Kimia, Fakultas Sains dan Teknologi, UIN Syarif Hidayatullah Jakarta

Show Abstract | Original Source | Check in Google Scholar | Full PDF (555.621 KB)

Abstract

Pemilihan monomer fungsional yang efektif untuk sintesis Molecular Imprinted Polymer (MIP)untuk diazinon dapat dilakukan dengan pendekatan kimia komputasi dengan menerapkan metode semiempirik AM1. Proses seleksi menggunakan parametermomen dipol, energi interaksi, dan ikatan hidrogen yang terbentuk. Energi interaksi yang optimum menunjukkan kompleks yang terbentuk stabildan mengindikasikan MIP akan dapat terbentuk baik.Semua perhitungan pada penelitian ini dilakukan dengan menggunakan software Hyperchem 7.5. Hasil penelitian menunjukkan monomer fungsional efektif untuk prasintesis polimer tercetak diazinon yaitu akrilamida, asam akrilat, asam metakrilat, hidroksi etil metakrilat, asam urokanat, asam itakonat, dan asam urokanat etil ester. Hasil ini secara teoritik  dapat memberikan informasi mengenai monomer fungsional efektif yang dapat digunakan sebagai pertimbangan sintesis MIP untuk diazinon dengan selektivitas relatif baik.
Penggunaan Metode Semiempirik AM1 Untuk Pemilihan Monomer Fungsional Efektif Pada Prasintesis Polimer Tercetak Diazinon Saputra, Andrian; Wijaya, Karna; Ahmad, Mohd Noor; Tahir, Iqmal
VALENSI Vol 3, No 1 (2013): Jurnal Kimia Valensi Volume 3//No.1//Mei 2013
Publisher : Program Studi Kimia, Fakultas Sains dan Teknologi, UIN Syarif Hidayatullah Jakarta

Show Abstract | Original Source | Check in Google Scholar | Full PDF (52.205 KB)

Abstract

Abstrak   Pemilihan monomer fungsional yang efektif untuk sintesis Molecular Imprinted Polymer (MIP) untuk diazinon telah dilakukan dengan pendekatan kimia komputasi dengan menerapkan metode semiempirik AM1 (Austin Model 1). Proses seleksi menggunakan parameter momen dipol, energi interaksi, dan ikatan hidrogen yang terbentuk. Energi interaksi yang optimum menunjukkan kompleks yang terbentuk stabil dan mengindikasikan MIP akan dapat terbentuk baik. Semua perhitungan pada penelitian ini dilakukan dengan menggunakan software Hyperchem 7.5. Hasil penelitian menunjukkan monomer fungsional efektif untuk prasintesis polimer tercetak diazinon yaitu akrilamida, asam akrilat, asam metakrilat, hidroksi etil metakrilat, asam urokanat, asam itakonat, dan asam urokanat etil ester. Hasil ini secara teoritik dapat memberikan informasi mengenai monomer fungsional efektif yang dapat digunakan sebagai pertimbangan sintesis MIP untuk diazinon dengan selektivitas relatif baik. Kata kunci: monomer fungsional, semiempirik AM1, energi interaksi, diazinon, MIP Abstract Selection of the effective functional monomer for MIP synthesis of diazinon has been done using computational chemistry approach applying AM1 (Austin Model 1) semiempirical method. Selection processes have been done based on dipole moment, interaction energy, and hydrogen bonding parameters. An optimum interaction energy shows stability complex and it indicates a good MIP produced by diazinon and the monomers. All calculations on this paper is run using Hyperchem 7.5 software. The result showed that the effective functional monomers for presynthesis of diazinon imprinted polymer are acrylamide, acrylic acid, methacrylic acid, hydroxyethyl methacrylate, urocanic acid, itaconic acid, and urocanic acid ethyl ester. Theoretically this result is expected as an early information to synthesis MIP of diazinon with good selectivity. Keywords: functional monomer, AM1 semiempirical, interaction energy, diazinon, MIP
Pengaruh Pemanasan Terhadap Kristalinitas Dan Parameter Kisi Nanokomposit Silika-Zirkonia Montmorillonit K10 Dan Silika-Besi Oksida Montmorillonit K10 Sekewael, Serly J.; Wijaya, Karna; ., Triyono
Indo. J. Chem. Res. Vol 6 No 1 (2018): Edisi Bulan Juli (Edition For July)
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

Show Abstract | Original Source | Check in Google Scholar | Full PDF (596.015 KB)

Abstract

The thermal treatment of the silica-zirconia montmorillonite K10 and silica-ferri oxide montmorillonite K10 nanocomposites at 300 and 500 °C has been carried out, respectively as part of a study of their function as the catalyst. The heating effect on the crystallinity and the lattice parameter calculation of both nanocomposites was studied using XRD and FTIR instruments. The results showed that the nanocomposite silica-zirconia montmorillonite K10 has a thermal resistance and the crystallinity better than the silica-ferri oxide montmorillonite K10, and both have values varying lattice parameters.
Karakterisasi dan Aplikasi Katalis Nikel-Molibdenum Teremban pada Zeolit Alam Aktif untuk Hidrorengkah Tir Batubara Sugianto, Dwi Julian; Wijaya, Karna; Tahir, Iqmal
Jurnal Natur Indonesia Vol 16, No 1 (2014)
Publisher : Jurnal Natur Indonesia

Show Abstract | Original Source | Check in Google Scholar | Full PDF (743.026 KB)

Abstract

Preparation and characterization of nickel-molybdenum catalysts supported on activated natural zeolite over hydrorackingof coal tar have been done. Modification of catalyst was included activation of zeolite by HCl 6N, wet impregnation of Ni-Mo metal and leaching the Ni-Mo from zeolite surfaces with EDTA solution.The parameters of catalyst have been determinedi.e acid site number, the ratio of Si/Al, crystallinity, content of Ni-Mo metal, specific surface area, total pore volume, and poreaverage diameter. The hydrocracking of coal tar was carried out at the optimum temperature (450°C) by flowing H2 gas (flowrate of 20 mL/min) on the coal tar with ratio of feed:catalyst was 10:1. The resulting liquid product was analyzed by GC/GCMS.The result showed that catalytic hydrocracking with ZAA catalyst had the highest conversion of liquid products,which were 40.51% (w/w) compared to Ni-Mo/ZAA catalyst gave 28.61% and Ni-Mo/ZAA(E) gaves 28.06% (w/w). Thehighest light fractions (67.63% (w/w)) produced by using Ni-Mo/ZAA catalyst and the highest medium fractions wereproduced over ZAA catalyst which was 36.61% (w/w) and the highest total conversion on the product with Ni-Mo/ZAA(E)catalyst produced was 50.05% (w/w). The product analyzed with GC-MS result on the 9th highest peak showed that thehydrocracking products resulted over Ni-Mo/ZAA mostly were phenol and its derivatives.Keywords: catalyst, coal tar, hydrocracking, natural zeolite, nickel-molybdenum
SYNTHESIS OF Zn(II)/SILICA BY SOL-GEL METHOD AS AN ANTIBACTERIAL MATERIAL AGAINST Escherichia coli AND Staphylococcus aureus Anggraini, Dian; Wijaya, Karna
Berkala Ilmiah MIPA Vol 23, No 2 (2013)
Publisher : FMIPA UGM

Show Abstract | Original Source | Check in Google Scholar

Abstract

Synthesis of Zn(II)/silica by sol-gel method as antibacterial material against Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus) has been done. Sol-gel process was carried out by reacting tetraethoxysilane, H2O, HCl, ethylene glycol and ZnCl2. The ZnCl2 concentrations varied 0.25, 0.5; 0.75, 1, and 1.25 M. Heat treatment were done by combination of microwave and oven, while the process of aging gel Zn(II)/silica carried out for 24 h and or without going through the process of aging. The Zn(II)/silica was then characterized by Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction method (XRD), and Transmission Electron Microscopy (TEM). The Zn(II) ions concentration that released from Zn(II)/silica was determined by AAS. Zn content in Zn(II)/silica was determined by X-Ray Fluoresence (XRF). Porosity of materials were determine by monolayer adsorption of N2 gas. Antibacterial test was done by calculate the number of bacteria surviving after contact with Zn(II)/silica by plate count method and compared to silica.The XRD results showed that Zn(II)/silica phase composed of amorphous SiO2 and y-ZnCl2. The  porosity test results showed that Zn(II)/silica has surface area of 517.698 m2/g. The XRF analysis results showed that ZnCl2 0.25 M produced the optimum Zn content 35,60% in Zn(II)/silica. Zn(II)/silica synthesized by heating in the oven at 150oC for 3 h after dried by microwave and aged resulted in the optimum Zn(II)/silica due to the least release of Zn(II) ions from Zn(II)/silica when analyzed by AAS (5.51%). Zn(II)/silica with concentration of 163 ppm could kill E.coli from concentration of 1.5 x106 CFU/mL to 0 CFU/mL in 2,5 h contact time, and reduces S.aureus concentration 1,2 x 106 CFU/mL with a contact time of 24 h. While the silica with the same concentration to that of the Zn(II)/silica showed no antibacterial effect against E.coli and S.aureus.