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SINTESIS SILIKA MCM-41 DAN UJI KAPASITAS ADSORPSI TERHADAP METILEN BIRU Ahda, Mustofa; Kunarti, Eko Sri
PHARMACIANA Vol 3, No 1: Mei 2013
Publisher : PHARMACIANA

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Abstract

Telah disintesis MCM-41 dengan variasi waktu hidrotermal 18, 24, 36, 48 jam menggunakan agen pengarah struktur cetiltrimetilammonium bromida (CTAB). Hasil penelitian menunjukkan bahwa waktu hidrotermal mempengaruhi intensitas dan indeks bidang (ao). Sintesis MCM-41 dengan waktu hidrotermal 24 jam menghasilkan intensitas tertinggi yang menunjukkan bahwa MCM-41 memiliki kristalinitas terbaik.sedangkan uji kapasitas MCM-41 tersebut memiliki kemampuan adsorpsi terhadap metilen biru sebesar 37,037 mg/g.
INKORPORASI TITANIA PADA MATRIKS SILIKA DAN PENGARUHNYA TERHADAP AKTIVITAS FOTOKATALITIK TITANIA PADA DEGRADASI METIL ORANYE Kunarti, Eko Sri; Wahyuni, Endang Tri; Hapsari, Indi Annisa
Jurnal Manusia dan Lingkungan (Journal of People and Environment) Vol 18, No 1 (2011)
Publisher : Pusat Studi Lingkungan Hidup Universitas Gadjah Mada

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Abstract

Telah dilakukan preparasi dan karakterisasi nanokristal titania terinkorporasi silika (nanokomposit titania-silika) disertai dengan pengujian aktivitas fotokatalitiknya untuk degradasi metil oranye. Preparasi dilakukan melalui proses sol-gel pada suhu kamar diikuti dengan perlakuan termal pada temperatur 500 o C. Pengaruh penambahan silika terhadap karakter nanokomposit yang terbentuk telah dikaji dalam penelitian ini. Karakterisasi dilakukan dengan metode difraksi sinar-X, spektrometri inframerah, spektrometri fluoresensi sinar-X serta spektrometri uv-vis difusi reflaktansi. Proses degradasi dilakukan dengan sistem batch di dalam reaktor tertutup yang dilengkapi dengan lampu UV 40 watt. Hasil penelitian menunjukkan bahwa penambahan matriks silika menyebabkan pembentukan ikatan cross-linking Si-O-Ti dan oxygen vacancies dalam titania. Inkorporasi titania pada matriks silika dapat meningkatkan stabilitas dan energi celah pita serta sifat fotokatalisis titania bebas.
KINETICS AND BALANCE ADSORPSI ION KROMIUM (III) IN SOLUTIONS ON SILICA AND COMPOUND MODIFICATION OF SILICA RESULTS SYNTHESIS FROM GREEN RICE DRINKS Sulastri, Siti; Nuryono, Nuryono; Kartini, Indriana; Kunarti, Eko Sri
Jurnal Penelitian Saintek Vol 19, No 2: Oktober 2014
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/jps.v19i2.3501

Abstract

This study will examine the nature of silica and modified silica in the interaction with Cr (III) ion as an adsorbate. Properties that will be studied are kinetics and equilibrium of Cr (III) adsorption in solution. Studies begins with determining the existence of Cr (III) ion in solution at various pH values, the presence of adsorbent at various pH values, and the adsorption of Cr (III) ion in solution by the adsorbent at various pH values. Based on this data set also can determined some values, e.g the maximum adsorption capacity (notated as Qmax), and the equilibrium constant, the RL value that determined the nature of adsorption were favorable or not favorable. Similarly to the Freundlich isotherm. Adsorption kinetic and equilibrium were performed at pH 5. Each adsorbent has a different kinetic model. All of adsorbents has compatibility with Langmuir 2 isotherm model, and on these condition had favorable adsorption of Cr (III) ion. The highest Qmax value is at HSSN. In the Freundlich isotherm model can be stated that all of the adsorbent is favorable for the adsorption process of Cr (III) ion in solution..
ADSORPTION OF CA(II), PB(II) AND AG(I) ON SULFONATO-SILICA HYBRID PREPARED FROM RICE HULL ASH Sulastri, Siti; Nuryono, Nuryono; Kartini, Indriana; Kunarti, Eko Sri
Indonesian Journal of Chemistry Vol 11, No 3 (2011)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.21392

Abstract

In this research, adsorption of Ca(II), Pb(II) and Ag(I) in aqueous solution onto sulfonato-silica hybrid (SSH) prepared from rice hull ash (RHA) has been studied. The preparation of SSH adsorbent was carried out by oxidation of mercapto-silica hybrid (MSH) with hydrogen peroxide (H2O2) solution 33%. MSH was prepared, via sol-gel process, by adding 3 M hydrochloric acid solution to mixture of sodium silicate (Na2SiO3) solution and 3(trimethoxysilyl)-1-propanthiol (MPTS) to reach pH of 7.0. Solution of Na2SiO3 was generated from destruction of RHA with sodium hydroxide solution followed with heating at 500 °C for 30 min. The SSH produced was characterized with Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analyzer, energy dispersive X-ray (EDX) spectroscopy and determination of ion-exchange capacity for sodium ion (Na+). The adsorption of Ag(I) and Ca(II) were conducted in a batch system in various concentrations for one hour. The adsorbent ion was calculated based on difference of concentrations before and after adsorption process determined using atomic absorbance spectrophotometric (AAS) method. The adsorption character was evaluated using model of isotherm Langmuir and Freundlich adsorption to calculate the capacity, constants and energy of adsorption. Result of characterization by EDX and FTIR showed qualitatively that SSH has been successfully synthesized which were indicated by appearance of characteristic absorbance of functional group namely silanol (Si-OH), siloxane (Si-O-Si), methylene (-CH2-) and disappearance of mercapto group (SH). The XRD data showed amorphous structure of SSH, similar to silica gel (SG) and MSH. The study of adsorption thermodynamics showed that oxidation of MSH into SSH increases the ion-exchange capacity for Na+ from 0.123 to 0.575 mmol/g. The change in functional group from silanol to mercapto and from mercapto to sulfonato increases the adsorption capacity of Ca(II). However, the capacity order of adsorbents for both ions of Pb(II) and Ag(I) in aqueous solution is MSH > SG > SSH.
SINTESIS DAN KARAKTERISASI SILIKA GEL DARI ABU SEKAM PADI YANG DIIMOBILISASI DENGAN 3-(TRIMETOKSISILIL)-1-PROPANTIOL Mujiyanti, Dwi Rasy; Nuryono, Nuryono; Kunarti, Eko Sri
Jurnal Sains dan Terapan Kimia Vol 4, No 2 (2010)
Publisher : Jurnal Sains dan Terapan Kimia

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Abstract

Telah dilakukan sintesis dan karakterisasi hibrida merkapto silika (HMS) yangdiperoleh dari hasil pengolahan abu sekam padi(ASP) dari daerah Jambidan,Banguntapan, Bantul.HMS dibuat dengan menambahkan HCl 3M pada campuran senyawa 3-(trimetoksilil)-1-propantiol (TMSP) dan larutan Na2SiO3 yang dihasilkan dari peleburanASP dengan NaOH hingga pH 7 (netral). Karakterisasi hasil dilakukan denganspektroskopi inframerah (FTIR) dan difraktometer sinar-X (XRD).Hasil karakterisasi dengan FTIR mengindikasikan keberhasilan pembuatan HMSdengan munculnya serapan dari gugus-gugus fungsional seperti : gugus metilen (-CH2-),silanol (Si-OH) dan siloksan (Si-O-Si). Dari data XRD diketahui bahwa HMS yangterbentuk mempunyai struktur amorf.Kata kunci : Adsorben, hibrida merkapto-silika (HMS), abu sekam padi (ASP)
KARAKTERISTIK PENGIKATAN ION Cd(II) dan Cu(II) DALAM PEMBUATAN HIBRIDA AMINO-SILIKA IMPRINTED IONIK Buhani, Buhani; Narsito, Narsito; Nuryono, Nuryono; Kunarti, Eko Sri
Jurnal Sains dan Terapan Kimia Vol 5, No 2 (2011)
Publisher : Jurnal Sains dan Terapan Kimia

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Abstract

Karakteristik pengikatan ion Cd(II) dan Cu(II) pada polimer imprinted ionik (PII)dari hibrida amino-silika (HAS) yang disintesis menggunakan senyawa 3-aminopropiltrimetoksisilan (3-APTMS) dengan tetraetil ortosilkat (TEOS)sebagai prekursor telah dipelajari. Kontribusi pengikatan ion Cd(II) dan Cu(II)pada sintesis material HAS imprinted ionik Cd(II) dan Cu(II) didominasi olehinteraksi kimia melalui interaksi elekstrotatik sebesar 43,06 ± 0,42 % untukCd-HAS dan 40,96 ± 0,21% untuk Cu-HAS, sedangkan pembentukan ikatankovalen sebesar 50,91 ± 0,25 % untuk Cd-HAS dan 54,87 ± 0,20 % untuk Cu-HAS.Kata kunci : Imprinted ionik, hibrida amino-silika, 3-aminopropiltrimetoksisilan
STUDI KINETIKA ADSORPSI AL-MCM 41 TERHADAP METILEN BIRU Ahda, Mustofa; Sutarno, Sutarno; Kunarti, Eko Sri
Pharmaciana Vol 6, No 1 (2016): Pharmaciana
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/pharmaciana.v6i1.3290

Abstract

The synthesis and kinetics studies of Al-MCM 41 of the methylene blue adsorption have been done. The observations of the adsorption kinetics are very important parameter in the adsorption process. This is the higher of adsorption kinetics tend to faster adsorption process. The results of characterization of Al-MCM 41 have a wall thickness is 15.173 Å, Pore Volume Pore is 0.584 cm3/g, Pore Diameter is 30.446 Å, Surface Area is 995.513 m2/g. The results of the adsorption kinetics of Al-MCM 41 to  methylene blue adsorption follows pseudo second order with coefficient of determination (r2) value of 0.999 and the value of adsorption rate constant of Al-MCM 41 is 10-2 g.mg-1.min-1.
PENGARUH PEMANASAN TERHADAP KEMAMPUAN TANAH DIATOMIT SEBAGAI ADSORBEN LOGAM KROM (III) DAN KADMIUM (II) Nuryono, Nuryono; Kunarti, Eko Sri; Narsito, Narsito
Jurnal Kimia Sains dan Aplikasi Vol 3, No 2 (2000): Volume 3 Issue 2 Year 2000
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2838.951 KB) | DOI: 10.14710/jksa.3.2.41-51

Abstract

Telah dilakukan penelitian untuk mengkaji pengaruh pemanasan terhadap kemampuan tanah diatomit Sangiran, Sragen, Jawa Tengah terhadap kemampuannya mengadsorbsi logam Cr(III) dan Cd(II) dalam larutan. Sebelum proses adsorpsi dilakukan tanah diatomit dikarakterisasi keberadaan situs aktifnya dengan menggunakan spektrofotometri infra merah (IR) dan analisis termogravimetri (TGA). Adsorpsi dilakukan melalui sistem bath dengan mencampurkan sejumlah sampel tanah dengan larutan logam pada temperatur kamar, 30°C, pH 4,0- 6,0 (tanpa pengaturan) untuk Cr(lll), dan 5.0 - 7,0 untuk Cd(II). Proses serupa dilakukan terhadap tanah diatomit yang telah dipanaskan pada temperatur yang berbeda (300°C, 500°C dan 900°C). Pengaruh lama kontak dan konsentrasi awal logam terhadap adsorpsi dievaluasi untuk menentukan kapasitas, tetapan adsorpsi, dan energi adorpsi. Hasil penelitian menunjukkan bahwa tanah diatomit melepaskan semua molekul air pada pemanasan 580°C, dan kondensasi gugus silanol menjadi siloksan terjadi pada pemanasan 700°C. Pemanasan tanah diatomit sampai 500°C dapat meningkatkan kemampuan mengadsorpsi ion Cr(III), sedangkan untuk adsorpsi ion Cd(ll) tidak berubah secara signifikan. Sebaliknya, pemanasan sampai 900°C mengakibatkan penurunan yang tajam terhadap kemampuannya mengadsorpsi baik ion Cr(III) maupun Cd(II). Kapasitas adsorpsi tertinggi untuk Cr(III), 205,3 mg/g, terjadi pada tanah setelah pemanasan 500°C, sedangkan untuk Cd(II), 14.93 mg/g, terjadi pada tanah setelah pemanasan 300°C. Tetapan adsorpsi berkisar 6.93 - 11,51 x 103 untuk Cd(II) dan 0,94- 1,58 x 103 untuk Cr(III), sedangkan energi adsorpsi berkisar 17,30- 18,55 kJ/mol untuk Cr(III) dan 21,49- 23,56 kJ/mol untuk Cd(ll).
SILVER NANOPARTICLES CAPPED WITH P-HYDROXYBENZOIC ACID AS A COLORIMETRIC SENSOR FOR THE DETERMINATION OF PARAQUAT Gusrizal, Gusrizal; Santosa, Sri Juari; Kunarti, Eko Sri; Rusdiarso, Bambang
Indonesian Journal of Chemistry ARTICLE IN PRESS
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.48806

Abstract

Highly stable silver nanoparticles capped with p-hydroxybenzoic acid were synthesized by reducing silver ion with p-hydroxybenzoic acid and used for the detection of paraquat. The synthesized silver nanoparticles, which are yellow, exhibited an absorption peak at 420 nm when measured with a UV-visible spectrophotometer due to the surface plasmon resonance. In the presence of paraquat, the color of silver nanoparticles changed from yellow to purple accompanied by the appearance of a new peak at 580 nm in addition to the peak at 420 nm. In order to obtain optimum experimental conditions, temperature, and time of reaction were optimized, and the ratio of absorbance obtained at 580 nm and 420 nm (A580/A420) were monitored. The A580/A420 is proportional to the concentration of paraquat. Under the most favorable condition, the calibration curve showed a high level of linearity ranging from 6.0 × 10?4 to 1.0 × 10?3 M, and the detection limit was found to be 8.30 × 10?6 M. Silver nanoparticles capped with p-hydroxybenzoic acid was found to be useful for the colorimetric determination of paraquat in the aqueous medium.
KAJIAN ADSORPSI Ag(S2O3)23- DALAM LIMBAH FOTOGRAFI PADA ADSORBEN KITIN DAN ASAM HUMAT TERIMOBILISASI PADA KITIN Khoerunnisa, Fitri; Santosa, Sri Juari; Kunarti, Eko Sri
Jurnal Pengajaran Matematika dan Ilmu Pengetahuan Alam Vol 9, No 2 (2007): Jurnal Pengajaran MIPA
Publisher : Faculty of Mathematics and Science Education, Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18269/jpmipa.v9i2.327

Abstract

This work was started with isolation of humic acid from peat soil and chitin from crab shell, immobilization of humic acid on chitin, and characterization of adsorbents of C and HAC. Optimum condition was studied by interacting the adsorbents with Ag(S2O3)23- in a synthetic solution on various  of pH from 2 to 10. Adsorption rate was studied by interacting the adsorbent with Ag(S2O3)23- in the synthetic solution on various time from 2 to 120 minutes. The determination of the energy and the capacity of adsorption were studied by interacting the adsorbent with Ag(S2O3)23- on various initial concentration from 2 to 75 ppm. Moreover, the mechanism of adsorption was studied by applying a sequential desorption using H2O, Na2EDTA 0.1 M, KSCN 0.5 M, and KOH 1 M. The adsorption of Ag(S2O3)23- in photography wastewater on C and on HAC were studied at the same condition as obtained for the synthetic solution. The result showed that pH 2 was the optimum adsorption condition for Ag(S2O3)23- in the synthetic solution on both C and HAC adsorbents. Ag(S2O3)23- in the synthetic solution was chemically adsorbed on C and on HAC, involving energy adsorption of 22.74–23.30 kJ/mole, respectively. Adsorption of Ag(S2O3)23- on C was faster than that on HAC with the rate constants for adsorbent C and HAC were 73 x 10-4 and 46 x 10-4 minute-1, respectively. Adsorption capacity of Ag(S2O3)23- on C and on HAC were 2.107 x 10-4 and 1.818 x 10-4 mole/g, respectively. The amount of Ag(S2O3)23- in photography wastewater that was adsorbed on C and on HAC were 13.52 and 12.47 mg/L, respectively. The hydrogen bonding and ion exchange were the dominant mechanism of adsorption.Key words: Ag(S2O3)23-, adsorption, chitin, immobilization, humic acid.