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Indonesian Journal of Chemistry

ijc
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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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Vulcanization Kinetics of Natural Rubber Based On Free Sulfur Determination Abu Hasan; Rochmadi Rochmadi; Hary Sulistyo; Suharto Honggokusumo
Indonesian Journal of Chemistry Vol 13, No 1 (2013)
Publisher : Universitas Gadjah Mada

The determination of free sulfur in the rubber vulcanizates provided significant representation of vulcanization reaction. In this research, the effects of vulcanization temperature, the mixing method of carbon black into rubber, the ingredients mixing sequence and the type of carbon black were studied on masticated and milled natural rubber in which the reaction was observed by un-reacted sulfur determination. The results showed that higher vulcanization temperature provided faster vulcanization reaction and greater reaction rate constant. Similarly, the mixing sequence of ingredient and carbon black into rubber influenced the rate of vulcanization reaction. The subsequent ingredients mixing sequence, in this case, resulted in higher vulcanization rate compared to that of the simultaneous one. However, the mixing method of carbon black into rubber brought small effect on the rate of vulcanization reaction. The type of carbon black applied was observed to influence the reaction rate of vulcanization. Smaller particle sizes of carbon black gave larger reaction rate constant. In this case, the type of carbon black N 330 gave faster vulcanization rate than that of N 660.

MATARANINE A AND B: A NEW DIASTOMERIC INDOLE ALKALOID FROM Alstonia scholaris R.Br. OF LOMBOK ISLAND Surya Hadi
Indonesian Journal of Chemistry Vol 9, No 3 (2009)
Publisher : Universitas Gadjah Mada

Alstonia scholaris R. Br., (Apocynaceae) is widely distributed in Indonesia and in Lombok Island, the plant locally known as ";lolon nita"; has been used to treat malaria. To locate potential bioactive compounds, acid-base extraction was carried out. From the base fraction, two new indole alkaloids with diastomeric structure, named Mataranine A and B, were isolated. The structures of the two alkaloids were elucidated on the basis of UV, NMR and mass spectral data.

IMPREGNATION OF 2-MERCAPTOBENZOTHIAZOLE ON DIATOMACEOUS EARTH AND ITS APPLICATION AS MERCURY(II) ADSORBEN IN AQUEOUS MEDIUM Agung Purwanto; Narsito Narsito
Indonesian Journal of Chemistry Vol 1, No 3 (2001)
Publisher : Universitas Gadjah Mada

An adsorbent was prepared by impregnating 2-mercaptobenzo-thiazole onto polystirene treated diatomaceous earth support. This adsorbent was then applied to adsorb mercury(II) in aqueous medium. The mercury(II) adsorption characteristics of the adsorbent was studied by the use of the original diatomaceous earth as reference. Interaction of mercury(II) and both of diatomaceous earth as well as MBT-diatomaceous were performed in a aqueous batch system to include the following parameters: (a) medium acidity and (b) mercury(II) adsorption characteristic on MBT-diatomaceous with and without the present of other metal ions. In the present work quantification of mercury(II) adsorption was done by determining the mercury concentration left in the solution after adsorption. A cold vapour-generation atomic absorption spectroscopy technic was used in this determination.The experiment results show, that the adsorption affinity of MBT-diatomaceous is higher than the original diatomaceous earth. The total adsorption energy of mercury(II) for diatomaceous earth (24.702 kJ/mol) and MBT-diatomaceous (46.942 kJ/mol) suggest that the interaction is chemisorption. The mercury(II) maximum adsorption on diatomaceous earth is obtained at pH 6, while similar adsorption on MBT-diatomaceous practically was not influenced by pH changes. The present of other metals, i.e. Fe(III), Co(II), Ni(II), Cu(II), Cd(II) and Zn(II) in solution does not give any appreciable influence to the adsorption affinity of MBT-diatomaceous to mercury(II); the total sum of the mercury(II) adsorbed is constantly high, almost 100 %.

DIPRENYLATED XANTHONE FROM THE STEM BARK OF KANDIS GAJAH (Garcinia griffithii) Elfita Elfita; Supriyatna Supriyatna; Husen H. Bahti; Dachriyanus Dachriyanus
Indonesian Journal of Chemistry Vol 8, No 1 (2008)
Publisher : Universitas Gadjah Mada

A diprenylated xanthone, 1,5-dihydroxy-3-methoxy-4,7-diprenylxanthone (1) had been isolated the first time from the dichloromethane extract of the stem bark of Garcinia griffithii, together with 1,7-dihydroxyxanthone (2) and polyisoprenylated benzophenone, guttiferone I (3). The structure of these compounds were determined on the basis of spectroscopic data including UV, IR, 1H NMR, 13C NMR, HMQC, HMBC and COSY.

SYNTHESIS OF C-METHYL-4,10,16,22-TETRAMETHOXYCALIX[4]ARENE FROM PHENOL USING BF3-METHANOL AS THE CATALYST Jumina Jumina; Evi Triwulandari; Chairil Anwar
Indonesian Journal of Chemistry Vol 5, No 1 (2005)
Publisher : Universitas Gadjah Mada

C-Methyl 4,10,16,22-tetramethoxycalix[4]arene has been synthesized from phenol. The reaction performed consisted of methylation of phenol, acetylation of methyl phenyl ether, reduction of p-methoxyacetophenone, and cyclization of p-methoxy-(1-hydroxyethyl)benzene to form C-methyl-4,10,16,22-tetramethoxycalix[4]-arene using BF3-methanol as the acid catalyst. Methylation of phenol was done by reacting phenol with solution of NaOH to generate sodium phenoxide salt. This mixture was strirred at reflux for 0.5 hours. Dimethyl sulphate was added and the reflux was continued for 2,5 hours. The product obtained was methyl phenyl ether, which was found as a colorless liquid in 99.0% yield. Acetylation of methyl phenyl ether was carried out in chloroform using acetic anhydride as the acetylating agent and anhydrous aluminium chloride as the catalyst. The addition of acetic anhydride and anhydrous aluminium chloride was done in two portions. The first portion was 0.967 g of acetic anhydride and 1.4 g of anhydrous aluminium chloride. The second portion was 0.54 g of acetic anhydride and 0.6 g of anhydrous aluminium chloride. The product obtained was found as a reddish yellow liquid in 69.6% yield. Reduction of p-methoxyacetophenone as the acetylation product was done using NaBH4 in ethanol at reflux for 2.5 hours. From this reaction, p-methoxy-(1-hydroxyethyl)benzene was obtained as a brown viscous liquid in 44.9% yield. Cyclization of p-methoxy(1-hydroxyethyl)benzene was done using BF3-methanol as the acid catalyst for two days at room temperature. The product obtained from this cyclization was found as a brown very viscous liquid in 87.3% yield. Identification of reaction products were carried out using Infra Red (IR) Spectrophotometer, Proton Nuclear Magnetic Resonance (1H NMR) spectrometer and Gas Chromatography-Mass spectroscopy (GC-MS).

ADSORPTION MODEL OF Mn2+, Cd2+ and Hg2+ IN THE WATER - SEDIMENT SYSTEMS ALONG CODE RIVER, YOGYAKARTA Muzakky Muzakky
Indonesian Journal of Chemistry Vol 8, No 3 (2008)
Publisher : Universitas Gadjah Mada

Prediction of adsorption model of Mn2+, Cd2+ and Hg2+ in water-sediment systems along Code River, Yogyakarta has been experimentally investigated. The aim of this investigation is to predict the transfer models based on isotherm adsorption of Mn2+, Cd2+ and Hg2+ metal ions from water into sediment. In addition, this investigation is expected to be able to inform the initial condition of Code River, dynamics, and the fate of Mn2+, Cd2+ and Hg2+ ions from upstream to downstream. Based on the investigation the transfer of Mn2+, and Cd2+ ions into sediment follows Langmuir adsorption model, with the coefficient determination (R2) of 0,9916 and 0,9799, while the value of the adsorption energy are 20,95 kJ/mol and 16,85 kJ/mol. The transfer of Hg2+ ion tend to follow Freundlich adsorption model. From the adsorption energies, it is proven that Mn2+ ion was chemically sorpted into the sediment, while Cd2+ ion will tend to be physically sorpted into the sediment. The binding strength of which ise in the order of Mn2+> Cd2+ and the adsorption energy of Hg2+ion couldnot be determined.

The Effect of Salinity on the Release of Copper (Cu), Lead (Pb) And Zinc (Zn) from Tailing Apriani Sulu Parubak; Eko Sugiharto; Mudjiran Mudjiran
Indonesian Journal of Chemistry Vol 1, No 1 (2001)
Publisher : Universitas Gadjah Mada

The effects of salinity on the release of copper (Cu), lead (Pb) and zinc (Zn) in tailing sediment have been studied by stripping voltammetry. The purpose of the research is to know the effect of salinity on the release of metals with certain pH, conductivity and variety of metals. Simultaneous determination of copper, lead and zinc in tailing was done by Differential Pulse Anodic Stripping Voltammetry (DPASV) onto hanging mercury drop electrode (HMDE) and nitric acid 65% as support electrolyte. The limit of detection for this method 0.60 µg/L, 0.150 µg/L and 0.238 µg/L for copper, lead and iMc respectively. The stripping solution of 300/00 salinity with pH= 7.85, conductivity= 46.62 mS/cm gives the amounts of released metals as follows :14.867 µg/L Cu, 0.976 µg/L Pb and 6.224 µg/L Zn. These results are higher as compared with the results from 15 0/00 salinity with pH= 7.66, conductivity= 23.22 mS/cm that give released metals of Cu= 7.988 µg/L, Pb= 0.311 µg/L and Zn= 4.699 µg/L. the results from ANOVA suggest that this is due to different in salinity of the solution. It also found that the conductivity does not give any effect. It can be concluded that the higher salinity will that give higher concentration or released metals.

THE COMPOSITION AND THE CONTENT OF PIGMENTS FROM SOME DYEING PLANT FOR IKAT WEAVING IN TIMORRESE REGENCY, EAST NUSA TENGGARA Neltji Herlina Ati; Puji Rahayu; Soenarto Notosoedarmo; Leenawaty Limantara
Indonesian Journal of Chemistry Vol 6, No 3 (2006)
Publisher : Universitas Gadjah Mada

Ikat weaving is one of traditional-home industry using plant pigments as a dye which have not been known for their pigments composition. So, the research was carried out to know the composition and the content of pigments in young leaf teak, noni root, turmeric tuber, casuarine bark and betel-nut root. The result showed that pigment composition in young leaf teak consisted of β-carotene, pheophytine, phelargonydine 3-glucosyde, phelargonydine 3,7-diglucosyde, chlorophyllide and two other pigments that have not been identified. Most of the pigments composition in betel-nut root have not been identified, but one of them was condensed tanin. Noni root had pigment composition which consisted of hydrolised tanin, flavonoid and morindon. Pigment composition in turmeric tuber were curcumin, demethoxy curcumin and bis-demethoxy curcumin. Whereas casuarine bark had pigment composition which consisted of delphynidine, cyanydine and phelargonydine. The highest pigment concentration in young leaf teak, betel-nut root, noni root, tumeric tuber and casuarine bark was pheophytine, tanin condensation, morindon, curcumin and cyanidine, respectively.

CHROMIUM (III) ADSORPTION FROM AQUEOUS SOLUTION BY Rhizophora apiculata TANNINS C. W. Oo; K. Jain
Indonesian Journal of Chemistry Vol 7, No 2 (2007)
Publisher : Universitas Gadjah Mada

Adsorption of Cr3+ from aqueous solution by Rhizophora apiculata tannins was investigated in batch shaking experiments. Tannins extracted from R. apiculata mangrove barks was chemically modified with formaldehyde in the basic solution of sodium hydroxide. The performance of the produced adsorbent on the adsorption of Cr3+ was evaluated based on the effect of several parameters like initial pH, adsorbent dosage, initial Cr3+ concentration and contact time. Equilibrium adsorption data was analyzed by Langmuir, Freundlich, Sips and Dubinin-Raduskhevich (D-R) isotherms. The fitness of the isotherms to the experimental data was determined by non-linear regression analysis. Adsorption capacity calculated from Langmuir isotherm was found to be 10.14 mg Cr3+/g of adsorbent at optimum adsorption pH of 4.5. Mean energy of adsorption with the value of 10.35 kJ/mol indicated that adsorption Cr3+ on Rhizophora apiculata tannins followed ion-exchange reaction. Kinetic study showed that the adsorption process followed the pseudo second-order kinetic model.

ISOTOPIC CHARACTERIZATION OF ORGANIC MATERIALS LEACHED FROM LEAVES IN WATER OF MUNDARING WEIR DAM Markus Heryanto Langsa
Indonesian Journal of Chemistry Vol 10, No 1 (2010)
Publisher : Universitas Gadjah Mada

This study examined the organic constituents aquatically leached from leaf components of two tree species (wandoo eucalyptus and pinus radiate). In particular this study aimed to assess the stable isotope composition behaviour of dissolved organic carbon (DOC) from the residue leaves after leaching over five months. The changes in the stable carbon and nitrogen isotope compositions of the leached leaves materials were investigated using an elemental analyzer-isotope ratio mass spectrometry (EA-irMS). The stable isotope compositions were found to vary according to microbially-mediated alteration and decomposition. The average d13C content of the raw plant elements was consistent with the d13C values of terrestrial plants using a C3 photosynthetic pathway. The isotope compositions of leached materials of wandoo eucalyptus fresh leaf were continually depleted in d13C over the leaching period of three months. These variations correlated well with its DOC profile. Changes in d13C values may also relate to the differential leaching of the macromolecular precursors of the original material. Lignin, for example, has a typically low d13C and probably contributed to the decrease of d13C in residue of the plant materials.

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