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Coal Ash Characteristic from Bukit Asam as Raw Material for Ceramics Production Karo-Karo, Pulung; Sembiring, Simon
Jurnal ILMU DASAR Vol 9, No 2 (2008)
Publisher : Fakultas MIPA Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1323.743 KB)

Abstract

This study was carried out to characterize coal ash obtained from Bukit Asam, Tarahan Lampung, after the samples were sintered at various temperatures ranging from 900C - 1300C. The characteristics of the investigated samples included density, porosity, hardness, structure and microstructure. The results indicated that porosity decreased with increasing sintering temperature, while density and hardness increased with increasing temperature. The x-ray diffraction (XRD) study revealed that the main crystalline phase was silicon dioxide (SiO2), with the minor constituents of CaSiO2, MgSiO3, FeSiO4 and Ca12Al14O33. SEM investigations clearly demonstrated the presence of a fine crystallised phase dispersed in the microstructure.Keywords: Coal ash, sintering, microstructure, XRD
Pembuatan dan Karakterisasi Komposit Batako Ringan dengan Campuran Sekam Padi Sebagai Bahan Pengisi untuk Kontruksi Bangunan Redam Suara Pratama, Aris; Karo Karo, Pulung; Sembiring, Simon
Jurnal Teori dan Aplikasi Fisika Vol 2, No 1 (2014): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (810.593 KB) | DOI: 10.23960/jtaf.v2i1.1257

Abstract

Telah dilakukan penelitian dengan tujuan untuk mengetahui pengaruh sekam padi terhadap kuat tekan dan penyerapan redam suara pada batako sekam padi tersebut. Metode penelitian yang digunakan adalah metode padatan. Sampel sebanyak 21 batako berbentuk silinder dengan diameter 5cm dan tinggi 4cm. Variasi Semen 10%, 20% dan 30% dengan persentase volume. Bahan pengisinya berupa pasir 80-10% dan sekam 10-80% dengan jumlah total 100%. Karakterisasi yang dilakukan berupa uji fisis yaitu densitas, porositas dan uji mekanis yaitu uji kuat tekan, uji redam. Hasil uji karakterisasi densitassebesar 1.13-1.77 gr/cm3. Densitas yang paling besar adalah sampel S30SP10 yaitu 1.77 gr/cm3. Nilai porositas antara 6.39-46.55%. Uji kuat tekan antara 0.43-12.84Mpa. Kuat tekan yang paling besar adalah sampel S30SP10 karena kandungan semen yang besar sehingga memperkuat beton ringan tersebut. Uji redam suara tertinggi pada sampel S30SP60 dengan penyerapan sebesar 0.44. Selanjutnya uji konduktivitas termal dilakukan pada sampel S10SP80, S30SP40, S30SP50 dengan data hasil yaitu 0.81, 0.89, 1.09 W/moK.
Struktur Mikro dan Konduktivitas Listrik Keramik Cordierite dengan Penambahan Magnesium Oksida (0, 10, 15 wt %) Berbasis Silika Sekam Padi Tristiana, Ade Lia; Sembiring, Simon; Simanjuntak, Wasinton
Jurnal Teori dan Aplikasi Fisika Vol 5, No 1 (2017): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (469.223 KB) | DOI: 10.23960/jtaf.v5i1.1352

Abstract

Research was conducted to determine the effect of magnesium oxide 0, 10, and 15wt% to the microstructure and electrical conductivity of cordierite. Cordierite was made by commercial MgO and alumina and silica from rice husk which is extracted by sol-gel method. Synthesis of cordierite was done with solid state reaction method and sintering at 1250ºC for 3 hours. Microstructure cordierite analyzed by SEM/EDS, while the electrical conductivity was analyzed using LCR meter, as well as physical test include its density, porosity and shrinkage. The results showed that the addition of MgO has reduced density, and shrinkage of cordierite and increase porosity. Microstructure cordierite with the addition of MgO indicated that sample with a lot of pores and their agglomeration. Conductivity values decreased with the addition of 10% MgO and increased at 15% MgO.
Pengaruh Suhu Tinggi terhadap Karakteristik Keramik Cordierite Berbasis Silika Sekam Padi Sembiring, Simon; Manurung, Posman; Karo-Karo, Pulung
Jurnal Fisika dan Aplikasinya Vol 5, No 1 (2009)
Publisher : Jurnal Fisika dan Aplikasinya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (95.746 KB) | DOI: 10.12962/j24604682.v5i1.933

Abstract

This study was carried out to investigate the effect of high temperature on the functional groups, microstructure and physical characteristics of cordierite ceramics obtained from an aqueous solution of magnesium nitrate hydrate ((Mg(NO3)2.6.12H2O)), aluminium nitrate hydrate (Al(NO3)2.9.15H2O) and silica sols extracted from rice husk. The samples were sintered at temperature of 1000◦C, 1200◦C and 1400◦C. Functional groups and microstructural characteristics of cordierite ceramics were examined by FTIR and SEM, respectivelly. FTIR study shows that the absence of the vibration bands of Na-OH, Si-OH, C-O, Si-O-Si on the samples. However, the formation of cordierite structure was dominated on this high temperature. Microstructure results confirmed the presence of irregular morphology of the solid and compact phases. In addition, the densities, shrinkage andhardness of cordierite increase significantly with increasing temperature, but porosity decreases with increasingtemperature.
Coal Ash Characteristic from Bukit Asam as Raw Material for Ceramics Production Karo-Karo, Pulung; Sembiring, Simon
Jurnal ILMU DASAR Vol 9 No 2 (2008)
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1323.743 KB)

Abstract

This study was carried out to characterize coal ash obtained from Bukit Asam, Tarahan Lampung, after the samples were sintered at various temperatures ranging from 900C - 1300C. The characteristics of the investigated samples included density, porosity, hardness, structure and microstructure. The results indicated that porosity decreased with increasing sintering temperature, while density and hardness increased with increasing temperature. The x-ray diffraction (XRD) study revealed that the main crystalline phase was silicon dioxide (SiO2), with the minor constituents of CaSiO2, MgSiO3, FeSiO4 and Ca12Al14O33. SEM investigations clearly demonstrated the presence of a fine crystallised phase dispersed in the microstructure.
Pengaruh Suhu Kalsinasi Terhadap Karakteristik Komposit MgO-SiO2 Berbasis Silika Sekam Padi Kusuma, Vinindia; Sembiring, Simon; Pandiangan, Kamisah D
Jurnal Teori dan Aplikasi Fisika Vol 2, No 1 (2014): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (5265.66 KB) | DOI: 10.23960/jtaf.v2i1.1252

Abstract

Komposit MgO-SiO2 disintesis dari larutan MgNO3 dan silika sekam padi. Pada penelitian ini digunakan metode sol-gel pada proses pencampuran MgNO3 dengan sol silika sekam padi dengan komposisi magnesium oksida dan silika 1:1, 1:2 dan 1:3 serta suhu kalsinasi 700oC, 800oC, 900oC. Penelitian ini bertujuan untuk mengetahui pengaruh komposisi dan suhu kalsinasi terhadap uji aktivitas, struktur dan mikrostruktur komposit MgO-SiO2. Berdasarkan hasil uji aktivitas yang meliputi konversi sampel dengan perbandingan 1:1 dan suhu kalsinasi 800oC memiliki nilai tertinggi yaitu 90,7% dan viskositas terendah yaitu 11,7672 mm2/s disebabkan karena perubahan fasa dari MgO dan SiO2 dari amorf menjadi kristal. Berdasarkan hasil SEM pada suhu kalsinasi 700oC komposit MgO-SiO2 permukaan masih rata belum terlihat kristal. Sedangkan pada suhu kalsinasi 800oC kristla MgO sudah terbentuk dan menutupi permukaan silika ketika suhu kalsinasi 900oC silika tidak semua permukaan silika tertutupi MgO dan terdapat retakan. Hasil EDS memperlihatkan senyawa oksigen, potasium, sulfur, karbon, silikon dan magnesium.
Karakteristik Kekerasan dan Struktur Kristal Cordierite Berbasis Silika Sekam Padi dengan Penambahan Alumina (0, 20, 25, dan 30 wt%) Mawarty, Nindy Elyta; Sembiring, Simon; Situmeang, Rudy T.M.
Jurnal Teori dan Aplikasi Fisika Vol 6, No 1 (2018): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (230.638 KB) | DOI: 10.23960/jtaf.v6i1.1829

Abstract

The synthesis, phase structure and hardness analysis of cordierite ceramic has been done with addition of alumina 0, 20, 25, and 30wt%. Magnesium and alumina from Sigma-Aldrich has been used as raw materials while the silica was obtained from extraction of rice husk used 5% KOH and 10% HCl with sol gel method. This cordierite synthesis used solid state method and sintered at 1200oC for 3 hours. Hardness analysis was determined by Microhardness Tester while the phase structure was determined by X-Ray Diffraction (XRD). Hardness value that obtained for C0, C20, C25, and C30 were 50,03 : 52,44 : 35,69 : and 50,46 kgf/mm2 repeatedly. It was proved that excess alumina will increase hardness value. The XRD patterns revealed that cordierite, corundum, spinel, cristoballite, and periclase were formed in the samplesKarakteristik Kekerasan dan Struktur Kristal Cordierite Berbasis Silika Sekam Padi dengan Penambahan Alumina (0, 20, 25, dan 30 wt%)
Characteristics of Nanosize Spinel NixFe3-xO4 Prepared by Sol-Gel Method Using Egg White as Emulsifying Agent Situmeang, Rudy; Wibowo, Sukma; Simanjuntak, Wasinton; Supryanto, R.; Amalia, Rizki; Septanto, Mitra; Manurung, Posman; Sembiring, Simon
Indonesian Journal of Chemistry Vol 15, No 2 (2015)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (438.236 KB) | DOI: 10.22146/ijc.21204

Abstract

In this study, sol-gel method using egg white as emulsifying agent was applied to prepare nano size spinel NixFe3-xO4 (with x = 0.2–1). Sample preparation was carried out by mixing the solution of Fe(NO3)3.9 H2O and Ni(NO3)3.6 H2O with egg white, and then the sample was stirred thoroughly using magnetic stirrer. After freeze–drying process, the sample was subjected to calcination treatment and subsequently characterized. The phase composition was evaluated using the X-ray diffraction (XRD) technique, followed by quantitative analysis using Rietveld and Debye-Scherrer Methods. The functionality of the sample was identified using Fourier Transform Infrared (FTIR) spectroscopy, and surface morphology and elemental composition were analyzed using scanning electron microscopycoupled with electron dispersive spectroscopy (SEM/EDS). The results of XRD characterization indicated that materials consist of various crystalline phases, with NiFe2O4 as a major phase. FTIR Analysis revealed the existence of both Lewis and Brønsted–Lowry acid sites, with Lewis acid as the prominent site. The sample was found to display relatively homogeneous surface morphology, having the crystallite size in the range of 33 to 61 nm according to the Debye-Scherrer equation. The EDS data indicated that the ratio of Fe/Ni is in agreement with the composition of the raw materials used.
EFFECT OF PYROLYSIS TEMPERATURES ON COMPOSITION AND ELECTRICAL CONDUCTIVITY OF CARBOSIL PREPARED FROM RICE HUSK Simanjuntak, Wasinton; Sembiring, Simon; Sebayang, Kerista
Indonesian Journal of Chemistry Vol 12, No 2 (2012)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (480.238 KB) | DOI: 10.22146/ijc.21350

Abstract

The objective of this study was to evaluate the effect of pyrolysis temperatures on composition and electrical conductivity of carbosil produced from rice husk, by conducting pyrolysis experiments at three different temperatures of 200; 400; and 700 °C. The structure of the samples was characterized using Fourier Transform Infrared (FTIR) Spectroscopy and X-Ray Diffraction (XRD). The microstructure and elemental composition were characterized using Scanning Electron Microscopy/Energy Dispersive Spectroscopy (SEM/EDS), and the electrical conductivity was measured using four probe method. The FTIR analyses revealed the existence of Si-O-Si and Si-OH functional groups, but no functional groups associated with carbon, confirming the formation of carbosil. This formation of carbosil is also supported by the results of EDS analyses which show the presence of only three elements of C, O, and Si, respectively. The XRD results indicate that the carbosils are amorphous, suggesting that no transformation of carbon and silica into crystalline phase to the limit of the temperatures applied. The carbosil formation decreased with increasing of pyrolysis temperature. The microstructure of the carbosils indicates that the higher the temperature, the smaller the grain size of the samples. The values of electrical conductivity of the samples are in the range of 1.13 x 10-3 to 6.81 x 10-3/(Ω.m) with the application of 10 tones compression pressure, but the conductivities of the sample prepared at 200 °C were found to increase with increased compression pressure to six fold from 6.81 x 10-3 to 41.94 x 10-3/(Ω.m) by increasing compression pressure to 80 tones. Based on these conductivity values, the samples are considered as semiconductor, suggesting the potential use of the carbosil in semiconductor devices.
SYNTHESIS AND CHARATERISATION OF RICE HUSK SILICA BASED BOROSILICATE (B2SiO5) CERAMIC BY SOL-GEL ROUTES Sembiring, Simon
Indonesian Journal of Chemistry Vol 11, No 1 (2011)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (579.057 KB) | DOI: 10.22146/ijc.21425

Abstract

In this research, borosilicate ceramics were produced from rice husk silica. Preparation of borosilicate ceramics was conducted by mixing boron oxide sol from borax with silica sol extracted from rice husk. The boron oxide was produced by hydrolysis of borax using H2SO4 5%. The samples were synthesized with different compositions, with the ratios of silica to boron oxide are 8:1, 8:2, 8:3 and 8:4. The samples were sintered at 900 °C. Functional groups were examined using FTIR spectroscopic technique. Structural and microstructural characteristics were examined by XRD and SEM, respectively. The chemical resistance of borosilicate is evaluated by gravimetric method using H2SO4, HCl, NaOH and KOH. The FTIR study revealed that the main functional groups are Si-O-Si, B-O-B, and B-O-Si. The x-ray diffraction (XRD) study revealed that the main crystalline phases are borosilicate (B2SiO5) and boron oxide (B2O3). SEM investigations clearly demonstrated that the smaller particle size was found with increasing in boron oxide concentration. From the chemical resistance test carried out, it was obtained that the produced borosilicate possessed high resistance to acids and alkalis.