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Indonesian Journal of Chemistry

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Published by Universitas Gadjah Mada

ISSN : 14119420 EISSN : 24601578 DOI : -

Core Subject : Science, Engineering,

Chemical Engineering, Chemistry & Bioengineering Chemistry

Indonesian Journal of Chemistry is an International, peer-reviewed, open access journal that publishes original research articles, review articles, as well as short communication in all areas of chemistry including applied chemistry. The journal is accredited by The Ministry of Research, Technology and Higher Education (RISTEKDIKTI) No : 21/E/KPT/2018 (in First Rank) and indexed in Scopus since 2012. Since 2018 (Volume 18), Indonesian Journal of Chemistry publish four issues (numbers) annually (February, May, August and November).

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Articles 1,981 Documents

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USE OF NANOSIZED CHROMIUM DOPED TiO2 SUPPORTED ON ZEOLITE FOR METHYLENE BLUE DEGRADATION Aarti Ameta; Indu Bhati; Rakshit Ameta; Suresh C. Ameta
Indonesian Journal of Chemistry Vol 10, No 1 (2010)
Publisher : Universitas Gadjah Mada

The photocatalytic degradation of methylene blue dye under visible light has been investigated using chromium modified titanium dioxide supported on zeolite (Cr-TiO2/zeolite). The photocatalyst was prepared by sol-gel method and characterized by X-ray diffraction and SEM. The rate of photodegradation of dye was monitored spectrophotometrically. The effect of pH, dye concentration, amount of photocatalyst and intensity of light on the rate of photocatalytic reaction was observed. The results showed that the use of Cr-doped TiO2 increased the rate of photocatalytic degradation of methylene blue as compared to untreated TiO2. The photocatalytic mechanism of Cr-TiO2 catalyst has been tentatively discussed.

EXTRACTION AND SPECIATION OF CHROMIUM(VI) AND CHROMIUM(III) AS ION-ASSOCIATION COMPLEXES OF TETRAMETHYLAMMONIUM-CHROMATE Valencia Widiyaningrum Wandoyo; Mudasir Mudasir; Roto Roto
Indonesian Journal of Chemistry Vol 6, No 2 (2006)
Publisher : Universitas Gadjah Mada

A specific, selective and simple method for speciation of chromium(VI) and chromium(III) has been developed. This method is based on the quantitative extraction of chromium(VI) and chromium(III) as an ion association of tetramethylammonium-chromate in methyl isobutyl ketone (MIBK), followed by back extraction and preconcentration with an acidic diphenylcarbazide (DPC) solution. Back extraction was applied to achieve further preconcentration by a final factor of 20. The chromium(VI)-DPC complex was determined by a UV-Visible spectrophotometer. The optimum conditions of this method are as follows, optimum wavelength at 545 nm, MIBK as organic solvent, 7.5 mL of nitric acid (65%) for each 100 mL sample, mole ratio of TMAC to Cr(VI) of 2x104:1, 5 min shaking time, mole ratio of DPC to chromium(VI) of 8:1, and immediate UV-Vis measurement after obtaining of back-extract. The calibration curve was linear in the concentration range 0.00-0.40 µg.mL-1 of chromium(VI) with a regression equation of Abs=0.0038+1.7427x, in which x was the chromium species concentration ( µg.mL-1). The correlation coefficient (r) for the curve was 0.9991 and the detection limit was found to be 0.946 µg.mL-1. The result of analysis and speciation of chromium in water samples from a river near a leather processing plant in Yogyakarta area showed that the total content of chromium was in the range of 0.04 - 0.05 µg.mL-1 consisting of 0.03 - 0.04 µg.mL-1 of chromium(VI) and 0.002 - 0.01 µg.mL-1 of chromium(III). This result indicates that the concentration of chromium in the river is still below the safety limit.

SYNTHESIS OF SOME CINNAMIC ACID DERIVATIVES: EFFECT OF GROUPS ATTACHED ON AROMATIC RING TO THE REACTIVITY OF BENZALDEHYDE Marcellino Rudyanto; Lanny Hartanti
Indonesian Journal of Chemistry Vol 8, No 2 (2008)
Publisher : Universitas Gadjah Mada

Synthesis of cinnamic acid and its six derivatives has been done by employing Knoevenagel reaction. Benzaldehyde, 4-butylbenzaldehyde, 4-t-butylbenzaldehyde, 4-butoxybenzaldehyde, 4-phenylbenzaldehyde, 5-bromo-2,4-dimethoxybenzaldehyde, and 5-bromo-2,3-dimethoxybenzaldehyde were reacted with malonic acid in pyridine – piperidine to give cinnamic acid (85,3%), 4-butylcinnamic acid (69,3%), 4-t-butylcinnamic acid (77,7%), 4-butoxycinnamic acid (64,5%), 4-phenylcinnamic acid (65,5%), 5-bromo-2,4-dimethoxycinnamic acid (53,2%) and 5-bromo-2,4-dimethoxycinnamic acid (57,2%), respectively. It was disclosed that 4-alkyl, 4-alkoxy, 4-aryl, dan 2-alkoxy groups decrease the reactivity of carbonyl carbon of benzaldehyde.

SYNTHESIS OF 4-ALLYL-2-METHOXY-6-AMINOPHENOL FROM NATURAL EUGENOL I Made Sudarma; Maria Ulfa; Sarkono Sarkono
Indonesian Journal of Chemistry Vol 9, No 1 (2009)
Publisher : Universitas Gadjah Mada

The aim of this preliminary research was to synthesize derivatives of eugenol such as 4-allyl-2-methoxy-6-nitrophenol (2) and 4-allyl-2-methoxy-6-aminophenol (3). The result could be used as a reference on the transformation of eugenol to its derivatives. Theoriticaly nitration of eugenol (1) by nitric acid could produced 4-allyl-2-methoxy-6-nitrophenol (2) and followed by reduction could achieved 4-allyl-2-mehtoxy-6-aminophenol (3). The formation of this product was analyzed by analytical thin layer chromatography (TLC) and GC-MS. These analysis showed the formation of product (2) and (3) were visible. TLC showed product (1) less polar than eugenol and gave orange colour, and supported by GC-MS which showed molecular ion at m/z 209 due to the presence of -NO2 by replacing one H at 6 position of eugenol. Product (3) was afforded by reduction of (2) with Sn/HCl and tlc analysis showed compound (3) more polar than eugenol (1) and (2) and supported by GC-MS which showed molecular ion at m/z 179 due to the presence of -NH2.

CORRELATION BETWEEN PREEXPONENTIAL FACTOR AND ACTIVATION ENERGY OF ISOAMYLALCOHOL HYDROGENOLYSIS ON PLATINUM CATALYSTS Triyono Triyono
Indonesian Journal of Chemistry Vol 4, No 1 (2004)
Publisher : Universitas Gadjah Mada

Arrhenius equation stated that reaction will proceed faster at higher temperature and with lower activation energy (Ea). Many literatures reported that preexponential factor (A) is constant for certain reaction and there is no relation between A and Ea. Experiment on the reaction of isoamylalcohol hydrogenolysis showed that logarithm of A increased linearly with Ea. The result of this investigation suggests that the rate of a process is affected by the number of active centers on the surface of a catalysts, which influences the value of the pre-exponential term in the expression for the rate constant of a reaction. An increase in the number of active centers corresponds to a higher value of A, the active centers would be less effective and is attended by a growth in the value of Ea. Therefore, reaction with lower activation energy will not always has higher reaction rate due to decreasing of Ea.

BIOACCUMULATION DYNAMICS OF HEAVY METALS IN Oreochromis nilotycus: PREDICTED THROUGH A BIOACCUMULATION MODEL CONSTRUCTED BASED ON BIOTIC LIGAND MODEL (BLM) Sri Noegrohati
Indonesian Journal of Chemistry Vol 6, No 1 (2006)
Publisher : Universitas Gadjah Mada

In estuarine ecosystem, sediments are not only functioning as heavy metal scavenger, but also as one of potential sources for heavy metals to the ecosystem. Due the capability of aquatic organisms to accumulate heavy metals, there is possibility of heavy metals to exert their toxic effect towards the organisms and other organisms positioned in higher trophic level, such as fish, and further to human beings. To understand the different processes of heavy metal bioaccumulation in a dynamic manner, a bioaccumulation model is required. Since bioaccumulation starts with the uptake of chemical across a biological membrane, the bioaccumulation model was constructed based on Biotic Ligand Model (BLM). The input for the model was determined from laboratory scale simulated estuarine ecosystem of sediment-brackish water (seawater:Aquaâ 1:1) for determining the heavy metal fractions in sediments; simulated Oreochromis nilotycus - brackish water (fish-water) ecosystem for determining the rate constants; simulated fish-water-sediment ecosystem for evaluating the closeness between model-predicted and measured concentration, routes and distribution within specific internal organs. From these bioaccumulation studies, it was confirmed that the internalization of metals into the cells of gills and internal epithelias follows similar mechanisms, and governed mostly by the waterborne or hydrophilic heavy metals. The level of hydrophilic heavy metals are determined by desorption equilibrium coefficients, 1/KD, and influenced by salinity. Physiologically, the essential Cu and Zn body burden in O. nilotycus are tightly homeostasis regulated, shown as decreasing uptake efficiency factor, EW, at higher exposure concentrations, while non essential Cd and Hg were less or not regulated. From the distribution within specific internal organs, it was revealed that carcass was more relevant in describing the bioaccumulation condition than liver. It is clear that every heavy metal has its own bioaccumulation dynamics, depend to the metal studied and environmental conditions, however the obtained parameters are applicable to bioaccumulation of Cd and Hg in natural estuarine ecosystem of Segara Anakan, Central Java.

MINIMIZE THE HYDROGENATION OF UNSATURATED FATTY ACID IN RUMEN WITH FORMALDEHYDE Nafly C. Tiven; Lies Mira Yusiati; Rusman Rusman; Umar Santoso
Indonesian Journal of Chemistry Vol 11, No 1 (2011)
Publisher : Universitas Gadjah Mada

This research aimed to know the ability of formaldehyde to protect unsaturated fatty acid of CPO on the hydrogenation process by rumen microbes. In this experiment, the in vitro fermentation of rumen fluid was carrying out. It was taken from the rumen-trocar of female sheep. The unsaturated fatty acid source was from CPO (Crude Palm Oil) which encapsulated by formaldehyde 37% within 0%, 1%, 2% and 3%. The data was analyzed by Completely Random Design with Duncan's New Multiple Range Test. The difference of means the treatments were tested by Duncan's New Multiple Range Test. Result showed that oleic and linoleic resulting from fermenting CPO protected by formaldehyde was increase if it was compared with the unprotected CPO. It can be concluded that encapsulated CPO with formaldehyde was able to prevent hydrogenating of unsaturated fatty acid, mainly oleic and linoleic.

PREPARATION AND CHARACTERIZATION THE NON-SULFIDED METAL CATALYST: Ni/USY and NiMo/USY Khoirina Dwi Nugrahaningtyas; Wega Trisunaryanti; Triyono Triyono; Nuryono Nuryono; Dian Maruto Widjonarko; Ari Yusnani; Mulyani Mulyani
Indonesian Journal of Chemistry Vol 9, No 2 (2009)
Publisher : Universitas Gadjah Mada

The two-new catalysts had been prepared by using the impregnation method according to Nugrahaningtyas [6] and Li [4]. One catalyst is of Nickel (Ni), supported on Ultra Stable Zeolite Y (USY), whereas the other one is NiMo supported on same supporting agent. These new catalysts are expected to be more effective when applied on the hydrotreatment reaction in standpoint of its capabilities on removing the unwanted-heteroatom. Characterization those two types of catalysts then carried out by using the criteria of acidity, porosity and, metal content. The result shows that these non-sulfide catalysts have several good characters that supporting their usefulness in hydrotreatment-catalytic reaction. In addition, catalyst NiMo/USY - 1 performs many ideal criteria as the best functional catalyst.

PRODUCTION OF 11 C-METHIONINE BY CYCLOTRON AVF JAERI Sri Hastini
Indonesian Journal of Chemistry Vol 2, No 1 (2002)
Publisher : Universitas Gadjah Mada

At the Takasaki-site of JAERI, an AVF cyclotron has been constructed for advanced radiation technology research. The cyclotron produces extracted beams particularly light and heavy ions of proton as well as deutron. Target chamber is available for production of 11CO2 a positron emitter radioisotope, by bombardment of proton from nitrogen gas as a target, by 14 N (p,a) 11C reaction. The use of incident energy on target was estimated to be 11 MeV for primary proton energy of 20 MeV and the beam current was 0,1 m A and the irradiation time was 10 minutes for production of 11CO2 and the yield was about 30 MBq (EOB)and for irradiation time 15 minutes and the beam current was 1 mA for production of 11C-Methionine, the yield was about 70 MBq (EOB). Remotely operated automatic and semiautomatic processing systems are used for the production of the 11 C-Methionine agent and the radiochemical purity of the product obtained was determined by High Performance Liquid Chromatography (HPLC) with cation exchange column was LC 10 AD MERCK LICHROSPHER 100 RP-18 and the mobile phase was 10 mM ammonium phormmate, the mean of retention time was 1,815 minutes and the radiochemical purity to be more than 90 %. The product was used for plant studies and visualized by PETIS (Positron Emission Tracer Imaging System)

TRANSPORT OF Cr(III), Cd(II), Pb(II), AND Ag(I) IONS THROUGH BULK LIQUID MEMBRANE CONTAINING p-tert-BUTYLCALIX[4]ARENE –TETRAETHYLESTER AS ION CARRIER Maming Maming; Jumina Jumina; Dwi Siswanta; Firdaus Firdaus; Hardjono Sastrohamidjojo
Indonesian Journal of Chemistry Vol 8, No 1 (2008)
Publisher : Universitas Gadjah Mada

The study on transport of Cr(III), Cd(II), Pb(II), and Ag(I) through bulk liquid membrane using p-tert-butylcalix[4]arene-tetraethylester as ions carrier has been conducted. The aims of this work are to determine the optimum condition, efficiency, and selectivity of transport of the carriers for those ions. Both optimum condition and efficiency of transport were obtained by determination of the concentration of transported ions with variation of source phase pH, ion carrier concentration, the nature of stripping agent in the target phase, and transport time. The ion transport selectivity of ion carrier was obtained from the ions transport competition experiments using equimolar mixtures. The amount of Cr(III), Pb(II), Cd(II), and Ag(I that was transported across liquid membrane was about 0, 10, 10 and 50 % respectively after 24 hours, except for Pb(II) (32 hours). The ion carrier is selective for Ag(I) where separation factor to Cd(II) was 16.0, that to Pb(II)was 42.8, and that to Cr(III) was infinite.

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