Articles

Found 13 Documents
Search

PEMBUATAN SISTEM PENGOLAH AIR BERSIH MENGGUNAKAN MATERIAL FOTOKATALIS TITANIA (TiO2) Sutanto, Heri; Hidayanto, Eko; Subagiyo, Agus; Widiyandari, Hendri; Nugroho, Indro Adi; Rahmawati, Zakiyah
Prosiding SNST Fakultas Teknik Vol 1, No 1 (2011): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 2 2011
Publisher : Prosiding SNST Fakultas Teknik

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Abstrak Telah berhasil dibuat sistem pengolah air bersih menggunakan material fotokatalis titania (TiO2). Sistem pengolah air bersih yang terdiri dari 2 pompa yang bertujuan untuk mengalirkan air kotor ke bak penampungan pertama, dan pompa kedua untuk mensirkulasikan air yang telah melewati biofilter untuk diolah melalui reaktor foto katalis TiO2 yang diaktifasi dengan menggunakan lampu UV sebanyak 2 buah masing-masing dengan daya 10 W. Lapisan tipis TiO2 dideposisi di atas substrat gelas dengan metode sol-gel teknik spray coating. Titanium Tetraisopropoxide 0,5 M dilarutkan ke dalam Diethylene Glycol dengan perbandingan mol DEG: (Ti(OC3H7)4 adalah 4:1 lalu diaduk dengan magnetic stirrer pada laju putar sebesar 1500 rpm selama 2 jam. Gel TiO2 hasil sintesis kemudian dimasukan ke dalam tabung spray-coater dan diberi tekanan Sebelum disemprot, substrat gelas dipanaskan pada temperatur 70oC untuk meningkatkan daya ikat antara larutan dengan substrat. Lapisan hasil penyemprotan selanjutnya di oven pada temperatur 200oC selama 30 menit dan sintering pada temperatur 450oC selama 2,5 jam. Hasil pengujian struktur kristal dengan x-ray diffractometer (XRD) menunjukkan bahwa semakin banyak pelapisan yang dilakukan menyebabkan kualitas kristal dari lapisan tipis TiO2 meningkat. Hal ini ditunjukkan dengan semakin menurunnya nilai FWHM. Selain itu, semakin banyaknya pelapisan yang dilakukan menyebabkan ukuran kristalit dari lapisan tipis TiO2 meningkat. Citra SEM lapisan tipis TiO2 menunjukkan bahwa semakin besar molaritas prekursor TiO2 menyebabkan kuantitas keretakan pada permukaan semakin menurun. Hasil pengujian BOD dan COD dari sistem pengolah air bersih menunjukkan bahwa sistem yang dibuat telah mampu mereduksi kandungan BOD hingga 5,76 mg/L dan COD hingga 25,22 mg/L. Kata kunci: Lapisan Tipis TiO2, Spray Coating, Foto Katalis, Substrat Gelas
Pembuatan dan Karakterisasi Komposit CNT/PVA Setyaningsih, Metri; Widiyandari, Hendri; Subagio, Agus
JURNAL SAINS DAN MATEMATIKA Volume 21 Issue 3 Year 2013
Publisher : JURNAL SAINS DAN MATEMATIKA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3648.641 KB)

Abstract

Komposit CNT/PVA telah dibuat dengan metode solution processing. Polyvinyl alcohol (PVA) dilarutkan dalam akuades bertemperatur 80°C, dan kemudian carbon nanotubes (CNT) ditambahkan ke dalam larutan tersebut dengan berbagai variasi rasio fraksi massa CNT/PVA sebesar 10, 20 dan 30%. Komposit CNT/PVA terbentuk setelah dikeringkan dalam oven bertemperatur 90°C. Sifat mekanik komposit CNT/PVA dikarakterisasi dengan uji tarik. Komposit CNT/PVA yang memberikan sifat mekanik terbaik selanjutnya digunakan sebagai acuan dalam pembuatan komposit dengan variasi ketebalan. Komposit dengan variasi ketebalan dibuat dengan 3 metode yaitu cetak tebal, cetak lapis tebal dan cetak lapis tipis. Analisis dari uji tarik menunjukkan bahwa komposit CNT/PVA dengan fraksi massa 20% CNT/PVA  menghasilkan modulus Young yang paling besar yaitu 137,710348 MPa. Metode cetak lapis tipis menunjukkan peningkatan yang lebih besar dibandingkan dengan metode cetak tebal, dan cetak lapis tebal. Komposit dengan 3 lapis dan ketebalan 0,94 mm menghasilkan modulus Young sebesar 212,825166 MPa dan peningkatan  modulus Young komposit CNT/PVA terhadap modulus Young dari PVA sampai 107,30%.
Deposisi Nanopartikel Titanium Dioksida (Tio2) di atas Gelas Transparan Konduktif dan Aplikasinya sebagai Elektroda Kerja pada Sel Surya Berbasis Dye (DSSC) Wahyudi, Bayu; Widiyandari, Hendri
JURNAL SAINS DAN MATEMATIKA Volume 19 Issue 4 Year 2011
Publisher : JURNAL SAINS DAN MATEMATIKA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2913.348 KB)

Abstract

Untuk mengantisipasi krisis energi beberapa dekade ke depan ini, sel surya tersensitasi zat pewarna (dye) telah dipertimbangkan sebagai salah satu sumber energi terbarukan yang sangat potensial. Dalam penelitian ini, telah berhasil dibuat elektroda aktif dari nanopartikel TiO2 yang dideposisikan diatas gelas transparan konduktif TCO dengan metode Doctor blade. Nanopartikel TiO2 yang telah dideposisikan kemudian dikarakterisasi menggunakan SEM (scanning electron microscopy) untuk mengetahui sruktur morfologi permukaan. Performa fotovoltaik dari sel surya DSSC telah diukur berdasarkan nilai voltase sirkuit terbuka (Voc) dan dikorelasikan terhadap rapat arus sirkuit pendek (Jsc) . Dari hasil pengujian terhadap performa DSSC diperoleh efisiensi maksimum dengan Voc = 0.68 V dan Jsc= 4.34 mA/cm2. Kata kunci: DSSC, nanopartikel TiO2, metode Doctor blade, fotovoltaik, efisiensi konversi
PEMBUATAN KOMPOSIT CARBON NANOTUBE-POLYVINYL ALCOHOL (CNT-PVA) SERTA EVALUASI SIFAT MEKANIKNYA Wahyudi, Tatang; Setyaningsih, Metri; Subagio, Agus; Widiyandari, Hendri; Pardoyo, Pardoyo; Ahyani, Musni
Arena Tekstil Vol 27, No 1 (2012)
Publisher : Arena Tekstil

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1329.846 KB)

Abstract

Perkembangan teknologi nanomaterial mendukung teknologi komposit. Komposit yang menggunakannanomaterial menghasilkan sifat mekanik yang lebih baik daripada komposit biasa. Komposit carbon nanotubes(CNT) berpotensi memiliki kekuatan tarik yang tinggi oleh adanya struktur tabung nanonya yang baik sebagaimatrik. Komposit CNT-PVA telah dibuat dengan metode pelarutan. Polyvinyl alcohol (PVA) dilarutkan dalam airbertemperatur 80°C, selanjutnya material CNT ditambahkan ke dalam larutan tersebut dengan variasi fraksi massaCNT terhadap PVA sebesar 10%, 20% dan 30%. Komposit CNT-PVA terbentuk setelah dikeringkan padatemperatur 80°C. Selanjutnya sifat mekanik komposit dikarakterisasi dengan uji kekuatan tarik. Hasil ujimenunjukkan bahwa komposit CNT-PVA dengan fraksi massa 20% CNT terhadap PVA menghasilkan modulusYoung yang paling besar yaitu 137,71MPa. Ketebalan komposit 0,94 mm yang dibangun oleh tiga lapis tipiskomposit CNT-PVA menghasilkan peningkatan modulus Young hingga 107,30%.
Degradasi Pewarna Methylene Blue (MB) Menggunakan Fotokatalis WO3/Fe2O3 dengan Perbantuan Cahaya Matahari Widiyandari, Hendri; Syam, Burhanudin
JURNAL SAINS DAN MATEMATIKA Volume 20 Issue 2 Year 2012
Publisher : JURNAL SAINS DAN MATEMATIKA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2830.296 KB)

Abstract

Degradation of dangerous pollutant with photocatalyst under solar or visible light radiation was a smart solution for environment pollution complication specifically for wastewater. an efficient photocatalyst which works at under wide spectrum from solar radiation. We reported the of tungsten oxide/ferric oxide (WO3/Fe2O3) composite with 6 variant weight ratio Fe additve (0%, 2%, 4%, and 6%).. Methylene blue photodegradation result showed, the decrease intensity of C/C0 concentration  more faster and constant especially for 6% additive co-catalyst Fe. Then, the photodegradation sample has result more pure than 5 sample others.   Keywords: WO3/Fe2O3, Photodegradation, photodeposition method, composite material, co-catalyst
Pengaruh Penggunaan Binder terhadap Densitas dan Kalor Pembakaran Briket dari Limbah Sagu Widiyandari, Hendri; Setiabudi, Wahyu; Subagio, Agus; Haryanti, Sri; Siahaan, Parsaoran; Tjahjana, Heru
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 3, No 02 (2013): IJAP VOLUME 03 ISSUE 02 YEAR 2013
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v3i02.1270

Abstract

Biomass fuel such as briquette is one of an alternative energy regarded to the shortage of the fosil fuel and rising its prices. The byproduct of sago starch industry is the waste that remain the environmental problem because of the odor. However this agricultur waste such as trunk cortex and fibre has a potential application as a raw material for briquette.The fibre and trunk cortex act as matrix material of briquette. The utilizing of sago waste as a biomass briquette and the effect of ratio of matrix/binder to the density, time of compustion and gross heat of the briquette have been elucidated sistematically. The analyzing of gross heat using adiabatic calorimetry indicated that the briquette prepared with the ratio of binder/matrix of 3:4 (mass ratio) had the maximum value of 3929.5 kal/g. The duration of combusion was proposional with density of the briquette.
STUDI PENGARUH UKURAN PIXEL IMAGING PLATE TERHADAP KUALITAS CITRA RADIOGRAF Sudin, Ahmas; Muhlisin, Zaenul; Widiyandari, Hendri
BERKALA FISIKA 2015: Berkala Fisika Vol. 18 No. 3 Tahun 2015
Publisher : BERKALA FISIKA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (408.382 KB)

Abstract

This study aims is to determine the image on imaging plate which has a different pixel sizes. In this research, the X-ray apparatus and Computed Radiography (CR) which is used in the diagnostic field was used. The three imaging plate each having size of 0.097 mm, 0.115 mm and 0.168 mm with stepwedge objects on it was used. The exposure factor was adjusted at 64.5 kV and 16 mAs. The each of imaging plate were exposure three times. The results of each radiograph imaging plate were measured by using a densitometer. By measuring the Stepwedge radiograph, it was obtained the density and contrast value of each imaging plate. Contrast value for each imaging plate were compared to obtain the imaging plate that have a higher contrast value. This research resulted that each different pixel sizes on the imaging plate would generate a different image quality. Keywords: pixel, imaging plate, image quality, contras, density
Synthesis of Titanium Dioxide (TiO2) Fine particle by Flame Spray Pyrolysis (FSP) Method using Liquid Petroleum Gas (LPG) as Fuel Widiyandari, Hendri; Purwanto, Agus; Gunawan, Vincensius; Widyanto, Susilo Adi
Reaktor Volume 17 No. 4 Desember 2017
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (518.824 KB) | DOI: 10.14710/reaktor.17.4.226-230

Abstract

This study aims to obtain titanium dioxide (TiO2) fine particle with a narrow size distribution by one step production via flame spray pyrolysis (FSP) using LPG (liquid petroleum gas) as a fuel source. The TiO2 particles were synthesized from the aqueous based precursor from dissolving of titanium (IV) isopropoxide to the acidic distilled water solvent. The effect of precursor concentration to the crystalline structure, morphology and size distribution of the TiO2 particles were systematically investigated. There were observed that the TiO2 has a uniform spherical shape with particle size around 200 – 500 nm. Increasing the precursor concentration resulted the size distribution shifted toward the bigger size. The crystalline structure of produced TiO2 showed the mixed phase of anatase and rutile and has a large specific surface area ~ 850,343 m²/g.
Studying Impact of Different Precipitating Agents on Crystal Structure, Morphology and Photocatalytic Activity of Bismuth Oxide Astuti, Yayuk; Arnelli, Arnelli; Pardoyo, Pardoyo; Fauziyah, Amilia; Nurhayati, Siti; Wulansari, Arum Dista; Andianingrum, Rizka; Widiyandari, Hendri; Bhaduri, Gaurav A.
Bulletin of Chemical Reaction Engineering & Catalysis 2017: BCREC Volume 12 Issue 3 Year 2017 (SCOPUS and Web of Science Indexed, December 2017)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (480.945 KB) | DOI: 10.9767/bcrec.12.3.1144.478-484

Abstract

Bismuth oxide (Bi2O3) is a well-studied photocatalyst for degradation of various environmental contaminants. In this research Bi2O3 has been synthesized by precipitation method using two different bases (NH4OH and NaOH). The samples thus obtained were then analyzed using FTIR, XRD, and SEM for surface functionalization, crystal structures and morphological differences, respectively. The Bi2O3 precipitated using NH4OH showed a flower like structure made up of individual plates having α-Bi2O3 crystal structure. The precipitate obtained using NaOH showed a honeycomb like flower structure with a mixture of both α-Bi2O3 and γ-Bi2O3 crystal structure. Degradation of methyl orange (MO) was used as a model system to test the photocatalytic activity of the bismuth oxide. The Bi2O3 synthesized using NH4OH showed superior photocatalytic degradation of methyl orange than the one synthesized using NaOH. Copyright © 2017 BCREC Group. All rights reservedReceived: 12nd April 2017; Revised: 24th June 2017; Accepted: 12nd July 2017; Available online: 27th October 2017; Published regularly: December 2017How to Cite: Astuti, Y., Arnelli, Pardoyo, Fauziyah, A., Nurhayati, S., Wulansari, A.D., Andianingrum, R., Widiyandari, H., Bhaduri, G.A. (2017). Studying Impact of Different Precipitating Agents on Crystal Structure, Morphology and Photocatalytic Activity of Bismuth Oxide. Bulletin of Chemical Reaction Engineering & Catalysis, 12 (3): 478-484 (doi:10.9767/bcrec.12.3.1144.478-484) 
Hydrazine and Urea Fueled-Solution Combustion Method for Bi2O3 Synthesis: Characterization of Physicochemical Properties and Photocatalytic Activity Astuti, Yayuk; Elesta, Prisca Putri; Widodo, Didik Setyo; Widiyandari, Hendri; Balgis, Ratna
Bulletin of Chemical Reaction Engineering & Catalysis 2020: BCREC Volume 15 Issue 1 Year 2020 (SCOPUS and Web of Science Indexed, April 2020)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (932.521 KB) | DOI: 10.9767/bcrec.15.1.5483.104-111

Abstract

Bismuth oxide synthesis using solution combustion method fuelled by hydrazine and urea has been conducted. This study aims to examine the effect of the applied fuels, urea and hydrazine, on product characteristics and photocatalytic activity in degrading rhodamine B dye. Bismuth oxide synthesis was initiated by dissolving bismuth nitrate pentahydrate (Bi(NO3)3.5H2O) in a nitric acid solvent. Fuel was added and then stirred. The solution formed was heated at 300 ºC for 8 hours. The product obtained was then calcined at 700 ºC for 4 hours. Bismuth oxide synthesized with urea (BO1) and hydrazine (BO2) as fuels both obtained form of yellow powder. The formation of bismuth oxide is indicated by the vibrations of the Bi–O–Bi and Bi–O groups and the crystal structure of a-Bi2O3 in both products. Photocatalytic activity test showed that BO1 has a photocatalyst activity in degrading rhodamine B higher than that of BO2 with constant values of  3.83×10-5 s-1 and 3.43×10-5 s-1, respectively. The high photocatalytic activity can be examined through several factors, such as: band gap values, crystal structure, morphology, and surface area, acquired as a result of the use of different fuels in the synthesis process. Copyright © 2020 BCREC Group. All rights reserved