Serly Jolanda Sekewael
Chemistry Department, Faculty Of Mathematics And Natural Sciences Pattimura University, Kampus Poka, Jl. Ir. M. Putuhena, Ambon 97134, Indonesia

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Karakterisasi Sifat Fisikokimia Komposit Besi Oksida-Montmorilonit Hasil Interkalasi Silikat Lempung Montmorilonit Serly Jolanda Sekewael
Jurnal Akta Kimia Indonesia (Indonesia Chimica Acta) Volume 1 No 1 - December 2008
Publisher : Hasanuddin University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20956/ica.v1i1.2450

Abstract

The preparation of iron oxide-montmorillonite composite has been done by intercalation of iron oxide into the silicates interlayer of montmorillonite. Montmorillonite and iron oxide-montmorillonite composite were characterized to observe some physical and chemical properties. The observed properties were basal spacing d001, determined by X-Rays Difractometer (XRD); surface morphology, analyzed by SEM/EDAX; specific surface area, distribution of pore radius and total pore volume, analyzed by Gas Sorption Analyzer; functional groups, analyzed by FTIR Spectrophotometer; and iron content, determined by X-Ray Fluorescent Analyzer (XRF). The characterization of montmorillonite and iron oxide-montmorillonite composite showed that the basal spacing d001, increased from 14.11 Å in montmorillonite to 16.85 Å in iron oxide-montmorillonite. Surface morphology of montmorillonite showed the laminated structure, while that of iron oxide-montmorillonite indicated a delaminated structure with the external oxides layered. Specific surface area increased from 69.71 m2/g to 126. 49 m2/g; total pore volume also increased from 50.70 x10-3 mL/g to 107.89 x10-3 mL/g. Generally, spectrum adsorption of montmorillonite and iron oxide-montmorillonite composite not different so far, stretching vibration O-H with Fe3+ does not exist on iron oxide-montmorillonite composite. The iron content also increased from 4.57 %(w/w) to 23.61 %(w/w).Keywords : montmorillonite clay, intercalation, iron oxide-montmorillonit composite.
Kinetic Study And Isoterm Adsorption Of Pb Metal In Ouw Village Clay Activated Ammonium Nitrate Salt Serly J. Sekewael; Hellna Tehubijuluw; Delvika R. Reawaruw
Indonesian Journal of Chemical Research Vol 1 No 1 (2013): Edisi Pertama (First Edition)
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

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Abstract

Kinetics studies and adsorption isotherms of Pb metal have been conducted on activated clay salts of ammonium nitrate (NH4NO3). Clays used are taken from Ouw village, Central Maluku. Clay activated by soaking in a solution of NH4NO3 700 ppm for 5 hours, then filtering and heating in a furnace at 550 oC for 4 hours. The optimum adsorption of metal ions Pb (II) by activated clay ammonium nitrate occurs at pH 4 with a contact time of 4 hours and followed the Freundlich adsorption isotherm pattern with a Kf value of 1.6193 x 10-8 mg/g and n value of 0.2059. Pb adsorption kinetics followed the pseudo-second-order Lagergren equation with the value of the adsorption rate constant (k2, ads) of 0.1248 g mg-1 min-1 and Xe value of 4.4783 mg/g.
Base Activated Clay And Its Application As Cation Exchanger To Reduce The Mg2+ AND Ca2+ Ions Concentration In The Well Catherina M. Bijang; Serly J. Sekewael; J. A. Koritelu
Indonesian Journal of Chemical Research Vol 1 No 2 (2014): Edisi Bulan Januari (Edition For January)
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

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Abstract

The research about base activated clay and its application as cation exchanger to reducing the concentration of ions Mg2+ and Ca2+ in the well water has been caried out. Base solution used for clay activation was NaOH with variation of concentration at, 0.5 M, 1 M, and 1.5 M. Particle size of clay also have been variated at 40 mesh, 60 mesh, and 80 mesh. The result of this research shown that the best cation exchanging for Mg2+ was found in clay with 60 mesh particle sizes and concentration of NaOH 0.5 M, whereas for Ca2+ was found in clay with 80 mesh particle sizes and concentration of NaOH was 1.5 M.
Synthesis Of 1-phenyl-4-(3’, 4’-dimethoxy phenyl)-1-Buten-3-on From Eugenol Candra Y. Tahya; Hanoch J. Sohilait; Serly J. Sekewael
Indonesian Journal of Chemical Research Vol 2 No 1 (2014): Edisi Bulan Juli (Edition For July)
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

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Abstract

The synthesis of 1-phenyl-4-(3’, 4’-dimethoxy phenyl)-1-buten-3-one from eugenol has been done through four reaction steps. The metilation of eugenol with dimethyl sulphate yields 81.81% of methyl eugenol. Oxymercuration-demercuration of methyl eugenol with mercury acetate yields 67.27% of methyl eugenyl alcohol. Oxidation of methyl eugenyl alcohol with pyridinium chloro chromate (PCC) yields 45.31% of methyl eugenyl ketone. Aldol condensation reaction of methyl eugenyl ketone with benzaldehide catalyzed by potasium hydroxyde yields 7.38% of 1-phenyl4-(3’,4’-dimethoxyphenyl)-1-buten-3-one. The purity of compounds was tested by GC and LC. The Elucidation of structure was analyzed by FTIR, GC-MS, LC-ESI-MS, and H-NMR.
Adsorption of Cd Metal Using Active Carbon From Cacao Shell (Theobroma cacao) Serly J. Sekewael; Jolantje Latupeirissa; Rosalina Johannes
Indonesian Journal of Chemical Research Vol 2 No 2 (2015): Edisi Bulan Januari (Edition For January)
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

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Abstract

The study on production of activated carbon from cacao shell (Theobroma cacao) was conducted by added 4 M HCl as activating agent. The results show that acidity of solid carbon active before activated with adsorption weight is 3.2865x10-3 mol.g-1 and after activated is 3.5052x10-3 mol.g-1. Active carbon result is used for the application at adsorption Cd with some variantion, that are optimum concentration 20 ppm and optimum time 80 min. Cd adsorption from active carbon was analyzed by AAS. The results are coeficient correlation (r2) 100 % followed Freundlich isotherm with KF value was 9.994 and n was -0.982.
Intercalation Of Clay By Surfactant And Its Application As Adsorbent Of Lead Ion Serly J. Sekewael; Hellna Tehubijuluw; Isabella C. Lefmanut
Indonesian Journal of Chemical Research Vol 3 No 1 (2015): Edisi Bulan Juli (Edition For July)
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

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Abstract

Research on natural clay intercalation with a surfactant has been done. The surfactant used is a quaternary ammonium salt type is cetil trimethyl ammonium bromide (CTAB). Intercalation process is carried out by stirring a suspension of clay and quaternary ammonium salt for 24 hours. After the intercalation process, palmitic acid are added, then the intercalated clay is used as an adsorbent ion Pb2+ distance between layers of clay after intercalated can be analyzed using X-ray diffraction. The distance between the layers increases from 15.99 to 19.45Ã…. Intercalated surfactant used to adsorb metals Pb2+ ions in solution with a variety of conditions such as contact time and concentration. The results of the analysis indicated using AAS then used to determine the adsorption capacity based on the optimum contact time optimum concentration and absorption. Adsorption capacity is equal to 8.092 mg/g.
Ekstraksi Dan Karakterisasi Kitosan Dari Kulit Udang Windu (Penaeus monodon) Serta Proses Depolimerisasi Kitosan Dengan Hidrogen Peroksida Berdasarkan Variasi Suhu Pemanasan Matheis F.J.D.P. Tanasale; Ivonne Telussa; Serly J. Sekewael
Indonesian Journal of Chemical Research Vol 3 No 2 (2016): Edisi Bulan Januari (Edition For January)
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

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Abstract

An extraction of chitin from shell of the tiger shrimp (Penaeus monodon), a convertion chitin into chitosan and depolymerization chitosan into oligochitosan using hydrogen peroxide based on variations in heating temperature have been done. Chitosan had depolymerized and it’s molecular weight had tested by end group analysis method and it’s degree of deacetylation had tested by UV-Vis spectrophotometry method. Oligochitosan had obtained from the conversion of chitin is isolated from the shell of tiger shrimp and from commercial chitin. The content of chitin obtained in tiger shrimp shells was 35.90% while the result of the conversion of commercial chitin into chitosan amounted to 62.33%. Characterization of functional groups using FTIR spectrophotometry showed that the conversion of chitosan from chitin commercial have absorption bands of 3617.56 (OH), 3050.47 - 3127.63 (-NH stretching), 2894.24 (-CH methylene), 1679.06 (-C = O), 1564.30 (-NH bending), and 1076.30 cm-1 (-CO-). The commercial chitosan which is characterized by FTIR spectrophotometric method also supports the results of the conversion of chitosan from chitin commercial. In the process of depolymerization of chitosan by hydrogen peroxide was found that the greater heating temperature was used, the smaller the percent yield and molecular weight of oligochitosan were at 40 oC, 50 oC, 60 oC and 70 oC gained weight average molecular oligochitosan were 1030.12 g/mol, 1019, 28 g/mol, 978.12 g/mol, and 908.82 g/mol, respectively
Pengaruh Pemanasan Terhadap Kristalinitas Dan Parameter Kisi Nanokomposit Silika-Zirkonia Montmorillonit K10 Dan Silika-Besi Oksida Montmorillonit K10 Serly J. Sekewael; Karna Wijaya; Triyono .
Indonesian Journal of Chemical Research Vol 6 No 1 (2018): Edisi Bulan Juli (Edition For July)
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30598//ijcr.2018.6-sjs

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.
Determination of Surface Acidity on The Natural and Synthetic Montmorillonite Clays by Titration Method Serly J. Sekewael
Indonesian Journal of Chemical Research Vol 9 No 2 (2021): Edition for September 2021
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30598//ijcr.2020.9-ser

Abstract

Determination of surface acidity on the natural and synthetic montmorillonite clays has been carried out using the acid-base titration method to count the number of bound acid sites per gram of clay. The total acidity of natural and synthetic montmorillonite surfaces obtained was 4.67 and 5.33 mmol/g, respectively. FTIR analysis results indicate the presence of functional groups from the tetrahedral and octahedral constituents. Both samples have similar absorption patterns. The similarity of absorption patterns was followed by a decrease in intensity and shift in some absorption bands, and the appearance of new absorption bands.
Kinetics and Isotherm Study of Ion Phosphate Adsorption by Lontor Natural Clay Nurul Ikhsan; Serly J Sekewael; Nurani Hasanela
Indonesian Journal of Chemical Research Vol 9 No 3 (2022): Edition for January 2022
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30598//ijcr.2022.9-ikh

Abstract

The clay used taken from Lontor Village, Central Maluku Regency, Banda Besar Island. The clay was activated at 350 °C for 3 hours using a furnace. This study aims to determine the effectiveness of physically activated Lontor natural clay in reducing levels of phosphate ions using the adsorption method. The adsorption capacity of clay is determined based on two parameters. The parameters are the optimum contact time used are 2, 3, 4, 5, and 6 hours and variations of the concentration are 10, 20, 30, 40, and 50 mg/L of phosphate. The concentration of phosphate adsorbed on the clay was measured by a UV-Vis spectrophotometer at a wavelength of 665 nm. The results showed that the optimum conditions for the adsorption of phosphate ions by Lontor natural clay were obtained at the contact time of 5 hours and the concentration of 40 mg/L. The adsorption of phosphate ions by Lontor activated natural clay followed the pseudo-second-order Lagergren adsorption kinetics model with a rate constant value (k2) of 3.39 x 10-1 g mg-1 min-1, and following the Freundlich adsorption isotherm models with a correlation coefficient (R2), Freundlich constant (Kf), and n values, respectively are 0.9513; 0.57 mg1-1/n L1/n/g, and 0.40 g/L.