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All Journal CAKRA KIMIA (Indonesian E-Journal of Applied Chemistry) INDONESIAN JOURNAL OF LEGAL AND FORENSIC SCIENCES Jurnal Kimia (Journal of Chemistry)

I Wayan Suarsa

Program Studi Kimia FMIPA Universitas Udayana, Bukit Jimbaran, Bali-Indonesia

Author-ID : 386671

Chemical Engineering, Chemistry & Bioengineering Chemistry Dentistry Electrical & Electronics Engineering Law, Crime, Criminology & Criminal Justice Medicine & Pharmacology

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SINTESIS DAN KARAKTERISASI KATALIS CaO-BENTONIT UNTUK REAKSI TRANSESTERIFIKASI MINYAK JELANTAH MENJADI BIODIESEL James Sibarani; Martha Zulfihardini; I Wayan Suarsa
CAKRA KIMIA (Indonesian E-Journal of Applied Chemistry) Vol 8 No 1 (2020): Volume 8, Nomor 1, 2020
Publisher : Magister Program of Applied Chemistry, Udayana University, Bali-INDONESIA

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ABSTRAK: Katalis basa heterogen paling banyak digunakan dalam produksi biodiesel. Tujuan penelitian ini untuk mendapatkan konsentrasi Ca(NO3)2 dan suhu optimum dalam sintesis katalis basa CaO-Bentonit sebagai katalis heterogen dalam proses reaksi transesterifikasi minyak jelantah menjadi biodesel. Bentonit terlebih dahulu diaktivasi dengan larutan NaOH 5% (b/v) kemudian dipanaskan pada suhu 500oC. Pembuatan CaO-Bentonit dilakukan dengan proses impregnasi larutan Ca(NO3)2 dengan konsentrasi 0,10M; 0,25M; dan 0,50M pada bentonit teraktivasi tersebut dan dikalsinasi pada suhu 500oC sampai 700oC selama 5 jam. Karakterisasi CaO-Bentonit dilakukan dengan FTIR, XRD dan BET. Hasil karakterisasi CaO-Bentonit menunjukkan bahwa konsentrasi Ca(NO3)2 dan suhu kalsinasi optimum berturut-turut adalah 0,10 M dan 700oC. Aplikasi dari katalis CaO-Bentonit tersebut pada proses transesterifikasi minyak jelantah menghasilkan biodiesel dengan rendemen sebesar 66,74% dan telah memenuhi standar baku mutu nasional Indonesia SNI. ABSTRACT: Heteregeneous base catalysts are commonly used in biodiesel production. The purpose of this study is to obtain the optimum concentration of aqueous solution of Ca(NO3)2 and the optimum temperature in the synthesis of CaO-Bentonite catalysts for transesterification reaction of waste cooking oil to produce biodiesel. Firstly, the bentonite was activated with NaOH 5% (w/v) following by calcination at 500oC. Secondly, the activated bentonite was impregnated with Ca(NO3)2 solution with various concentration of 0.10M, 0.25M, and 0.50M and calcinated at temperature of 500oC, 600oC, and 700oC. The characterizations of the CaO-bentonite were conducted by FTIR, RXD, and BET. The results revealed that the optimum concentration of Ca(NO3)2 and the optimum calcination temperature were 0.1 M and 700oC, respectively. Application of the CaO-bentonite catalyst on transesterification reaction of waste cooking oil to biodiesel yielded 66.74% of biodiesel fulfilling the Indonesian Standard Qualities.

PEMANFAATAN ARANG AKTIF DARI BATANG TANAMAN GUMITIR (Tagetes erecta) SEBAGAI ADSORBEN LOGAM BERAT Pb(II) DAN Cd(II) DENGAN AKTIVATOR NaOH I Made Siaka; Putu Dona Oka Putri; I Wayan Suarsa
CAKRA KIMIA (Indonesian E-Journal of Applied Chemistry) Vol 5 No 2 (2017)
Publisher : Magister Program of Applied Chemistry, Udayana University, Bali-INDONESIA

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ABSTRAK : Limbah batang gumitir mengandung selulosa cukup tinggi, sehingga dapat dimanfaatkan sebagai bahan dasar pembuatan arang. Arang yang dihasilkan tersebut dapat digunakan sebagai adsorben. Kualitas adsorben dapat ditingkatkan melalui proses aktivasi. Penelitian ini bertujuan untuk mengetahui perbedaan karakteristik antara arang tanpa pemanasan dengan yang dipanaskan sebelum diaktivasi dengan NaOH dan menentukan gugus fungsi, situs aktif, serta mengetahui waktu kontak dan pH optimum dalam adsorpsi Pb(II) dan Cd(II). Metode metilen biru digunakan untuk analisis luas permukaan, spektroskopi FTIR dan AAS digunakan untuk analisis gugus fungsi dan konsentrasi logam berat. Arang tanpa pemanasan sebelum aktivasi (KA1) memiliki karakteristik (kadar air, zat mudah menguap, abu total, dan karbon terikat) terbaik dan memenuhi baku mutu sesuai dengan standar SNI 06-3730-1995. Arang aktif KA1 juga memiliki luas permukaan dan bilangan iodin paling tinggi yaitu 1816,16 m2/g dan 1227,21 mg/g. Hasil identifikasi FTIR menunjukkan bahwa arang aktif KA1 mengandung gugus fungsi OH, COOH, C=O, dan CH3 dengan jumlah situs aktifnya sebesar 17,14x1020 molekul/g. Waktu dan pH optimum adsorpsi terhadap logam berat adalah 120 menit pada pH 5 untuk Pb(II) dan 60 menit pada pH 7 untuk Cd(II). Kata kunci :Gumitir, arang aktif, adsorben, logam berat ABSTRACT : Marigold stem wastes contain high enough cellulose, so it can be utilized as the basic material of making active carbon. The carbon produced can be used as an adsorbent. The quality of the adsorbent can be improved through the activation process. The aim of this study was to determine the characteristic differences between carbon without heating and heated before being activated with NaOH, as well as, to determine functional group, active site, and the optimum of contact time and pH in adsorption of Pb and Cd. The methylene blue method was used for analysing surface area, spectroscopy of FTIR and AAS was used for analysing functional groups and heavy metal concentrations. The carbon without preheating of activation (KA1) had the best characteristics (including, moisture content, volatile matter, total ash, and carbon bonded) and meets the quality standard in accordance with SNI 06-3730-1995 standard. The active carbon of KA1 also had the highest surface area and iodine number of 1816,16 m2/g and 1227,21 mg/g, respectively. Spectra of FTIR indicated that the active carbon of KA1 contained functional groups of OH, COOH, C=O, and CH3 with the number of active sites of 17.14x1020 molecules/g. The optimum time and pH of adsorption to the heavy metals was 120 minutes at pH 5 for Pb(II) and 60 minutes at pH 7 for Cd(II).

ADSORPSI KATION Pb(II) DAN Cr(III) OLEH BATU PADAS JENIS LADGESTONE TERAKTIVASI H2SO4 DAN NaOH Novita Rambu Atandawu; Ida Ayu Gede Widihati; I Wayan Suarsa
Jurnal Kimia (Journal of Chemistry) Vol. 7, No. 2 Juli 2013
Publisher : Program Studi Kimia, FMIPA, Universitas Udayana (Program of Study in Chemistry, Faculty of Mathematics and Natural Sciences, Udayana University), Bali, Indonesia

Adsorption of Pb (II) and Cr (III) cations by ladgestone activated with 2 N sulfuric acid, and 4 N sodium hydroxide have been studied. The activation aims to increase the adsorption capacity of the ladgestone which was characterized by measuring its specific surface area and the acidity of the ladgestone surface. In addition, equilibrium adsorption time, isotherm adsorption, and the adsorption capacity were also determined using atomic absorption spectrophotometry (AAS). The results showed that activation with 2 N sulfuric acid increased the acidity of ladgestone surface but it decreased the specific surface area, while activation with 4 N sodium hydroxide increased both the acidity and the specific surface area of the ladgestone. Hence, ladgestone activated with 4 N sodium hydroxide gave the highest adsorption capacity both for Pb (II) and Cr (III) which were 12.4976 mg/g and 12.4945 mg/g respectively.

PREPARASI KATALIS NIKEL-ARANG AKTIF UNTUK REAKSI HIDROGENASI ASAM LEMAK TIDAK JENUH DALAM MINYAK KELAPA Imam Rasidi; Anak Agung Bawa Putra; I Wayan Suarsa
Jurnal Kimia (Journal of Chemistry) Vol. 9, no. 1 Januari 2015
Publisher : Program Studi Kimia, FMIPA, Universitas Udayana (Program of Study in Chemistry, Faculty of Mathematics and Natural Sciences, Udayana University), Bali, Indonesia

This study aims to determine the optimum concentration of nickel nitrate in the formation of a nickel catalyst embedded on activated charcoal by impregnation method, the chemical and physical properties of nickel- coconut shell charcoal in partidular acidity and surface area, as well as the ability of nickel-charcoal catalyst activity in the hydrogenation of linoleic methyl ester in coconut oil. The study begins with a preparation of a mixture of activated charcoal with NaOH activation and preparation of nickel-activated charcoal catalyst with a wet impregnation method. At this stage FT-IR and UV-Vis were used to characterize the products. The resulting catalytic activity was tested with the hydrogenation reaction. Esterification was then performed and the result was determined with GC-MS. The optimum concentration of the catalyst was found to be 0,3M. The catalyst acidity was indicated by the presence of oxide groups including carboxyl, phenols, aldehydes and carbonyl groups, whereas the average surface area was about 21.8753 m2/g. The catalytic activity of nickel-activated carbon in the hydrogenation reaction of methyl ester was optimum at a pressure of 2 atmospheres.

AKTIVITAS ANTIOKSIDAN ANTOSIANIN DALAM EKSTRAK ETANOL KULIT BUAH NAGA SUPER MERAH (Hylocereus costaricensis) DAN ANALISIS KADAR TOTALNYA Ni Ketut Meidayanti Putri; I Wayan Gede Gunawan; I Wayan Suarsa
Jurnal Kimia (Journal of Chemistry) Vol. 9, No. 2 Juli 2015
Publisher : Program Studi Kimia, FMIPA, Universitas Udayana (Program of Study in Chemistry, Faculty of Mathematics and Natural Sciences, Udayana University), Bali, Indonesia

Dragon fruit is a plant that comes from dry tropical climate zones. Besides the flesh of the dragon fruits,,its skin can be used in food production as a natural food coloring and as the raw materials in cosmetics manufacturing. This is because of that the skin of the dragon fruit contains some compounds such as anthocyanin that can be used as an antioxidant. This study were aimed to determine the antioxidant activity, total anthocyanin content and the type of anthocyanins in the ethanol extract of super red dragon fruit skin. The determination of antioxidant activity of anthocyanin was carried out by the use of DPPH method, whereas the determination of the total content of anthocyanin was performed with a pH difference method using UV-Visibel spectrophotometer. The results showed that the optimum scavenger percentage of the extract was of 97.84% with IC50 value of 73.2772 mg / L, whereas the average levels of total anthocyanins obtained was of 58.0720 ± 0,0001mg / L. The type of anthocyanins contained in the ethanol extract of the skin of super red dragon fruit was sianidin showing a maximum peak at a wavelength of 547 nm.

TRANSESTERIFIKASI MINYAK BIJI KARET (Hevea brasiliensis) MENGGUNAKAN KATALIS HETEROGEN CANGKANG KEPITING LIMBAH SEAFOOD TERMODIFIKASI K2O N. K. D. Astuti; I N. Simpen; I W. Suarsa
Jurnal Kimia (Journal of Chemistry) Vol.13 No.1 Januari 2019
Publisher : Program Studi Kimia, FMIPA, Universitas Udayana (Program of Study in Chemistry, Faculty of Mathematics and Natural Sciences, Udayana University), Bali, Indonesia

The CaO heterogeneous catalysts can be prepared by CaCO3 calcination process, with one source of CaCO3 being a crab shell from seafood waste. The preparation of the heterogeneous catalyst was successfully carried out by modification with KOH using a wet impregnation method at 800oC for 5 hours. The purpose of this research is to determine the physical and chemical characteristics of heterogeneous catalyst of K2O-modified crab shell and to examine the heterogeneous catalyst of K2O-modified shells in converting rubber seed oil into biodiesel. The results showed that the lowest basic alkalinity possessed without modified catalyst (1.0428 mmol g-1) and the highest alkali possessed potassium-modified catalyst (1.8314 mmol g-1). Characterization of specific surface area of ??crab shells without and with modified K2O were relatively the same. The surface morphology of the catalyst without and K2O modified was uniform. The catalyst examination results for conversion of rubber seed oil (Hevea brasiliensis) to biodiesel, the optimum catalyst concentration of 3% and the molar ratio of oil:methanol of 1:9 capable converting to biodiesel with the yield of 91.05%. The content of biodiesel were stearic methyl ester, linoleic methyl ester, linolenic methyl ester, and palmitic methyl ester.

PEMBUATAN DAN KARAKTERISASI ARANG AKTIF DARI BATANG LIMBAH TANAMAN GUMITIR DENGAN AKTIVATOR ZnCl2 E. Sahara; D. E. Permatasaari; I W. Suarsa
Jurnal Kimia (Journal of Chemistry) Vol.13 No.1 Januari 2019
Publisher : Program Studi Kimia, FMIPA, Universitas Udayana (Program of Study in Chemistry, Faculty of Mathematics and Natural Sciences, Udayana University), Bali, Indonesia

The agricultural waste of gumitir plants stem can be used as an ingredient in producing an activated carbon. Some researchers have reported that the additions of phosphoric acid and NaOH as chemical activators have resulted in an activated carbon that met the SNI (Indonesian National Standard) 06-3730-1995 about technical activated carbon. The purpose of this study was to produce and characterize the activated carbon from the stem of gumitir plants carbonized at 300oC for 90 minutes with the use of ZnCl2 as the activator. The activation was carried out by adding ZnCl2 to an amount of carbon in various mole ratios. The characteristics of the activated carbon obtained were compared to the SNI. It was evident that the addition of 0.1 mole of ZnCl2 to 1 gram of the carbon produced an activated carbon that met the SNI standard, namely, water content of 5.00%, as content of 8.33%, volatile content of 950oC of heating of 7.36%, carbon content of 79,30%, iodine absorption capacity of 788.1271 mg/g, and methylene blue absorption capacity of 260.7917 mg/g. The surface area and surfae acidity of this carbon was of 677,6270 mg2/g and 0.3396 mmol/g, respectively. The functional group analysis of this activated carbon showed the presence of O-H, COOH, C-O aldehyde, alkaline C-C and C-H groups.

OPTIMASI JENIS PELARUT DALAM EKSTRAKSI ZAT WARNA ALAM DARI BATANG PISANG KEPOK (Musa paradiasiaca L. cv kepok) DAN BATANG PISANG SUSU (Musa paradiasiaca L. cv susu) I Wayan Suarsa; Putu Suarya; Ika Kurniawati
Jurnal Kimia (Journal of Chemistry) Vol. 5, No. 1 Januari 2011
Publisher : Program Studi Kimia, FMIPA, Universitas Udayana (Program of Study in Chemistry, Faculty of Mathematics and Natural Sciences, Udayana University), Bali, Indonesia

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Research on optimation of the type of solvent in natural dye found in extracs of kepok banana’s stem (Musa paradiasiaca L. cv kepok) and susu banana’s stem (Musa paradiasiaca L. cv susu) has been carried out. The obtained natural dye was determined for its rendement, natural dye groups, and the maximum absorption at 400 – 700 nm. Maseration of 100 g of dry powder of kepok banana and susu banana stems were conducted using four kinds of solvent namely, ethanol, acetone, and n-hexane. From kepok banana’s stem thick extracts 9.21 grams water; 3.19 grams ethanol; 1.23 grams acetone; and 0.21 grams n-hexane were obtained, whereas from susu banana’s stem were 12.13 grams water, 3.31 grams ethanol, 1.42 grams acetone, and 0.17 grams n-hexane thick extracts.Extracts obtained were concentrated, and then the rendements were determined. The redements from the kepok banana’s stem, were : water (36.84%), ethanol (12.67 %), acetone (4.92 %), and n-hexane (0.84%), whereas from susu banana’s stem, were : water (28.52%), ethanol (13.24%), acetone (5.68 %). and n-hexane (0.68%),The result of the fitochemical test showed that the natural dye on kepok and susu banana’s stem using four solvents was flavonoid. whereas tannin on both types of banana’s stem was only found in ethanol, acetone, and n-hexane extracts.Analysis using spectrophotometry UV-vis showed that n-hexane extracts gave the maximum absorption greater than the other solvents. The absorbance of kepok banana’s was 0.992 at 607.0 nm and of susu banana’s was 0.905 at 669.5 nm.

BERBAGAI WAKTU PENYIMPANAN SECARA SPEKTROFOTOMETRI UV-VIS Dewa Ayu Ika Pramitha; Ni Made Suaniti; I Wayan Suarsa
Jurnal Kimia (Journal of Chemistry) Vol. 8, No. 1 Januari 2014
Publisher : Program Studi Kimia, FMIPA, Universitas Udayana (Program of Study in Chemistry, Faculty of Mathematics and Natural Sciences, Udayana University), Bali, Indonesia

This paper describes the determination of lamivudine content in pulveres by UV-Vis spectrophotometry. The purpose of this study was to determine the stability of lamivudine in various storage times. In this study, the validation of the method of the determination of lamivudine standard was also investigated with the following results: the linear regression equation y = 0.045x - 0.005 with correlation coefficient (r2) of 0.9998. Furthermore the detection limits obtained was of 0.46 µg/mL, quantitation limit of 1.53 µg/mL, the coefficient of variation of 0.23%, accuracy of 3.59%, and the recovery was of 96.41%. The stability of lamivudine in the samples decreased during the observation period i.e. 0, 7, 14, 21, and 28 days, during which the contents of lamivudine obtained were 87.46%, 86.22%, 84.44%; 76, 87%, 79.38%, respectively.

SYNTHESIS AND CHARACTERIZATION OF PHOTOCATALYS Fe2O3 PILLARED MONTMORILLONITE DOPED TiO2 AND ITS APPLICATION FOR RHODAMINE B PHODODEGRADATION USING VISIBLE LIGHT IRRADIATION D. A. D. N. Dewi; I N. Simpen; I W. Suarsa
Jurnal Kimia (Journal of Chemistry) Vol.14 No.1 Januari 2020
Publisher : Program Studi Kimia, FMIPA, Universitas Udayana (Program of Study in Chemistry, Faculty of Mathematics and Natural Sciences, Udayana University), Bali, Indonesia

A montmorillonite clay modified with semiconductor metal can act as a photocatalyst material. Montmorillonite clays were chosen because of their natural characteristics which are easily to be modified and have high specific surface area. This research aims to modify montmorillonite clay into photocatalyst material. The montmorillonite clay was intercalated using Fe2O3 to produce Fe2O3-pillared montmorillonite clay, then doped with TiO2 to form a photocatalyst material Fe2O3-PILC / TiO2. Modifications were intended to increase the specific surface area and number of active photocatalyst sites and thus increase the ability of photodegradation. The characterization carried out included characterizing the pillar formation using X-ray Diffraction (XRD), specific surface area by the BET method (Bruneau, Emmet, and Teller), a the number of surface acid-base sites by the titration method. Photocatalyst with the best character was Fe2O3-PILC / TiO2 1: 3 with specific surface area, number of acid and base sites respectively 45,947 m2/g, 20,1736 x 1023 sites/gram and 19,0044 x 1023 sites/gram. The result of photodegradation at optimum condition with visible light at pH 3 using 400 mg photocatalyst was 99.84%. Keywords: photocatalyst, Fe2O3, montmorillonite clay, TiO2, rhodamine B

Co-Authors A. A. Bawa Putra D. A. D. N. Dewi D. E. Permatasaari Dewa Ayu Ika Pramitha Dwi Kurnia Putra R Emmy Sahara G. S. U. Mahaputra I Made Siaka I Nengah Simpen I Nengah Wirajana I Wayan Gede Gunawan I. A. Gede Widihati Ika Kurniawati Imam Rasidi Iryanti Eka Suprihatin James Sibarani M. W. Prayani Martha Zulfihardini N. D. Murdani N. K. D. Astuti N. W. S. P. Dewi Ni Desak Komang Ayu Hartani Ni G. A. M. Dwi Adhi Suastuti Ni Ketut Meidayanti Putri Ni Made Suaniti Ni Putu Widya Tironika Dewi Novita Rambu Atandawu Putu Dona Oka Putri Putu Suarya Satriya Putra Prakoso

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