scholarly journals Hydrophobically modified cotton fabric assisted separation of oil-water mixture

2021 ◽  
Author(s):  
Neha Bhatt ◽  
Abhilasha Mishra ◽  
Rekha Goswami
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Contact Angle ◽  
Particle Size ◽  
Free Energy ◽  
Cotton Fabric ◽  
Water Mixture ◽  
Mixture Separation ◽  
Oil Water ◽  
Scanning Electron

Abstract Superhydrophobic-superoleophilic fabrics were prepared and evaluated for oil-water mixture separation efficiencies. The nano-TiO2 and nano- SiO2 based coatings were done on the surface of the cotton fabric to create nanoscale roughness over the surface which was further modified by low energy material 1, 1, 3, 3- Hexamethyldisilazane (HMDS) and, polydimethylsiloxane (PDMS). Particle size and stability of prepared sol were characterized by particle size analysis and zeta potential. Coated cotton fabric samples were characterized by contact angle, contact angle hesteresis and surface free energy for its hydrophobic nature. Surface morphology was studied by scanning electron microscopy (SEM). The coated fabrics were found hydrophobic with low surface free energy values. The maximum contact angle was found 133° and lowest contact angle hysteresis was 5°. Scanning electron microscopy (SEM) confirmed the appearance of nanoscale surface roughness after coating of sols on cotton fabric. The average particle size and zeta potential values of silica sol was 61 nm and 137 mv whereas for titania sol it was found 344 nm and 200 mv respectively. The oil/water separation efficiency of coated fabric was also observed by different oil-water mixture. The coatings were found hydrophobic in nature and seem to be very useful for water/oil mixture separation.

Isolasi Dan Karakterisasi Bentonit Alam Menjadi Nanopartikel Monmorillonit

2018 ◽  
Vol 3 (1) ◽  
pp. 12 ◽  
Author(s):  
Zaimahwati Zaimahwati ◽  
Yuniati Yuniati ◽  
Ramzi Jalal ◽  
Syahman Zhafiri ◽  
Yuli Yetri
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Surface Morphology ◽  
Average Diameter ◽  
Particle Size Analyzer ◽  
Ft Ir ◽  
Scanning Electron ◽  
Sedimentation Processes

<p>Pada penelitian ini telah dilakukan isolasi dan karakterisasi bentonit alam menjadi nanopartikel montmorillonit. Bentonit alam yang digunakan diambil dari desa Blangdalam, Kecamatan Nisam Kabupaten Aceh Utara.  Proses isolasi meliputi proses pelarutan dengan aquades, ultrasonic dan proses sedimentasi. Untuk mengetahui karakterisasi montmorillonit dilakukan uji FT-IR, X-RD dan uji morfologi permukaan dengan Scanning Electron Microscopy (SEM). Partikel size analyzer untuk menganalisis dan menentukan ukuran nanopartikel dari isolasi bentonit alam. Dari hasil penelitian didapat ukuran nanopartikel montmorillonit hasil isolasi dari bentonit alam diperoleh berdiameter rata-rata 82,15 nm.</p><p><em>In this research we have isolated and characterized natural bentonite into montmorillonite nanoparticles. Natural bentonite used was taken from Blangdalam village, Nisam sub-district, North Aceh district. The isolation process includes dissolving process with aquades, ultrasonic and sedimentation processes.  The characterization of montmorillonite, FT-IR, X-RD and surface morphology test by Scanning Electron Microscopy (SEM). Particle size analyzer to analyze and determine the size of nanoparticles from natural bentonite insulation. From the research results obtained the size of montmorillonite nanoparticles isolated from natural bentonite obtained an average diameter of 82.15 nm.</em></p>

Microstructure Investigations of Streak Formation in 6063 Aluminum Extrusions by Optical Metallographic Techniques

2013 ◽  
Vol 19 (2) ◽  
pp. 276-284 ◽  
Author(s):  
George Vander Voort ◽  
Beatriz Suárez-Peña ◽  
Juan Asensio-Lozano
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Hot Extrusion ◽  
Magnesium Silicide ◽  
Precipitation Strengthening ◽  
Surface Appearance ◽  
Aluminum Extrusions ◽  
Extruded Products ◽  
Scanning Electron

AbstractThe present study investigates the effect of the solidification strategy for AA 6063 alloy on the surface appearance of anodized extrusions. The microstructure of the samples was analyzed using both light optical microscopy and scanning electron microscopy. Results show that if heavy segregation occurs from rapid solidification, coarse Mg2Si particles form, thus reducing the potential for precipitation strengthening by the finer β-Mg2Si developed in the solid state. Differentially-strained regions formed during hot extrusion induce differences in particle size for magnesium silicide (Mg2Si) precipitates. Anodizing generates surface roughness due to Mg2Si particle dissolution and AlFeSi decohesion, which is related to both particle size and deformation. During anodizing, an oxide layer forms on the surface of the extruded products, which can lead to streak formation, usually a subject of rejection due to unacceptable heterogeneous reflectivity.

Pervaporation Dehydration of Isopropanol–Water Mixtures Using Chitosan Zeolite–A Membranes

2012 ◽  
Author(s):  
Mohd. Ghazali Mohd. Nawawi ◽  
Le T. Ngoc Tram
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Glass Plate ◽  
Homogeneous Solution ◽  
Water Mixture ◽  
Zeolite A ◽  
Feed Concentration ◽  
Modified Chitosan ◽  
Chitosan Membranes ◽  
Scanning Electron

Kajian pervaporasi (PV) penyahidratan isopropanol (IPA) menggunakan membran kitosan terubahsuai telah dijalankan. Membran disediakan daripada kitosan dan diubahsuai menggunakan zeolite–A. Zeolit–A yang diketahui beratnya ditambahkan ke dalam pelarut berasid dan diaduk untuk menghasilkan larutan homogen. Kepingan kitosan kemudian ditambahkan ke dalam larutan tersebut dan diaduk semalaman. Pelbagai nisbah zeolit–A dan kitosan daripada 1:20 hingga 1:2 digunakan untuk menghasilkan membran kitosan terubahsuai. Larutan kitosan–zeolit–A dituangkan ke atas plat kaca dan dikeringkan pada suhu bilik. Membran yang dikeringkan kemudian dirawat dengan larutan alkali dan dibasuh di dalam air ternyahion. Sifat hidrofilik membran dikaji melalui ujian pengembungan. Ujian dijalankan dalam campuran 90 wt.% IPA–air. Keputusan menunjukkan bahawa darjah pengembungan berkurangan dengan penambahan zeolit–A. Sifat mekanikal membran dikaji untuk kekuatan tegangan dan pemanjangan pada takat putus. Kemudian, membran tersebut dikaji untuk pemisahan campuran IPA–air pada tekanan 720 mmHg di bawah vakum. Kepekatan suapan diubah daripada 0 hinga 95 wt.% IPA dan suhu suapan diubah daripada 30 hingga 70°C. Keputusan menunjukkan bahawa nisbah 1:8 antara zeolit dan kitosan menghasilkan kombinasi terbaik untuk mengubahsuai membran bagi pemisahan campuran IPA–air. Struktur morfologi membran kitosan–zeolit–A dengan nisbah 1:8 dan 1:2 berat zeolit–A/berat kiotsan dikaji menggunakan Scanning Electron Microscopy (SEM). Keputusan menunjukkan bahawa membran yang dihasilkan adalah padat dan tiada liang dapat diperhatikan. Penambahan zeolit tidak mengubah struktur membran. Kata kunci: Pervaporasi, penyahidratan, membrane, kitosan, zeolite-A, isopropanol Pervaporation (PV) dehydration of isopropanol (IPA) using modified chitosan membranes was studied. The membranes were prepared from chitosan and modified by using zeolite–A. Pre–weighed amount of zeolite–A was added into acidic solvent and stirred to produce homogeneous solution. Chitosan flakes were then added into the solution and stirred overnight. Various ratios of zeolite–A and chitosan from 1:20 to 1:2 were used to produce the modified chitosan membranes. The chitosan–zeolite A solution was casted on a glass plate and dried at room temperature. The dried membranes were treated with alkaline solution and thoroughly washed in deionized water. The hydrophilicity of the membranes was studied through the swelling test. The test was carried out in a 90 wt% IPA–water mixture. The result showed that the degree of swelling decreased with the increase of the amount of zeolite–A. The mechanical properties of membranes were also tested for the tensile strength and elongation at break. Then, the membranes were investigated for the PV separation of IPA–water mixtures at the permeate pressure of 720 mmHg under vacuum. The feed concentration was varied from 0 to 95 wt% IPA, and the feed temperature was varied from 30 to 70°C. The results showed that the ratio 1:8 of zeolite–A and chitosan produced the best combination to modify the membrane for the separation of water–IPA mixtures. The structural morphologies of the chitosan filled zeolite–A membranes with ratio 1:8 and 1:2 wt zeolite–A/wt chitosan was studied under Scanning Electron Microscopy (SEM). The results showed that the membranes were dense, and no pores were visible. The addition of the zeolite did not alter the structure of the membranes. Key words: Pervaporation, dehydration, membrane, chitosan, zeolite-A, isopropanol

scholarly journals PEMBUATAN DAN KARAKTERISASI NANOPARTIKEL EKSTRAK ETANOL TEMU KUNCI (Boesenbergia pandurata) PADA BERBAGAI VARIASI KOMPOSISI KITOSAN

2017 ◽  
Vol 6 (1) ◽  
pp. 31 ◽  
Author(s):  
Dessy Kurniasari ◽  
Sri Atun
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Particle Size Analyzer ◽  
Scanning Electron

Tujuan penelitian ini adalah untuk membuat dan mengetahui karakteristik nanopartikel dari ekstrak etanol temu kunci (Boesenbergia pandurata) dan rasio optimal variasi konsentrasi kitosan dan NaTPP dalam pembuatan nanopartikel temu kunci.            Pembuatan ekstrak temu kunci (Boesenbergia pandurata) menggunakan metode maserasi menggunakan etanol teknis 96% dilanjutkan evaporasi hingga terbentuk ekstrak kental temu kunci. Koloid nanopartikel dibuat dengan mencampurkan ekstrak temu kunci dalam etanol p.a, akuades, larutan kitosan dalam asam asetat glasial, dan larutan NaTPP. Ada 9 variasi komposisi antara larutan kitosan dan  NaTPP yakni rasio (5:1); (10:1); (15:1); (20:1); (3,33:1); (8:1); (9:1); (11:1); dan (12:1). Padatan dalam koloid nanopartikel dipisahkan dengan cara sentrifugasi. Endapan yang didapatkan disimpan dalam freezer. Koloid nanopartikel yang terbentuk dikarakterisasi menggunakan Particle Size Analyzer (PSA) dan Zeta Sizeruntuk mengetahui ukuran partikel dan nilai zeta potensial. Padatan yang didapatkan dari proses sentrifugasi selanjutnya dikarakterisasi menggunakan Scanning Electron Microscopy (SEM) untuk mengetahui kondisi morfologi padatan tersebut. Karakterisasi dengan KLT pada padatan yang didapatkan bertujuan untuk mengetahui kesamaan kandungan senyawa antara ekstrak etanol temu kunci dan ekstrak etanol temu kunci dalam sediaan berukuran nano.            Koloid nanopartikel yang telah dibuat berwarna kuning dan setelah di sentrifugasi terbentuk padatan berwarna kuning kecokelatan. Karakterisasi menggunakan PSA menunjukkan ukuran partikel pada rentang 389-877 nm sebanyak 98,1% pada rasio konsentrasi kitosan dan NaTPP = (8:1). Nilai rerata zeta potensial adalah 41,87 mV. Hasil foto SEM menunjukkan morfologi partikel yang memiliki permukaan yang tidak rata. Rf keenam sampel menunjukkan hasil bahwa senyawa yang terkandung dalam ekstrak etanol temu kunci maupun ekstrak etanol temu kunci dalam sediaan nanopartikel adalah sama. Kata Kunci : kitosan, NaTPP, ekstrak etanol temu kunci, KLT, SEM, PSA, zeta sizer

Novel Methods for Preparation and Surface Treatment of Nano-CaCO3

2013 ◽  
Vol 750-752 ◽  
pp. 336-339
Author(s):  
Fa Chao Wu ◽  
Teng Fei Shen
Keyword(s):  
Electron Microscopy ◽  
Heat Treatment ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Particle Size ◽  
Fourier Transform ◽  
Room Temperature ◽  
Transmission Electron ◽  
Reduce Energy Consumption ◽  
Scanning Electron

In this work, CaCO3 nanoparticles have been synthesized via heat-treatment of a new precursor. Effect of calcinations temperature on particle size has been investigated. The products were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). nanoCaCO3 was modified using chloroform as solvent and fatty acid as modifier atroom temperature. The advantage of this modification is that it can be proceed at room temperature and it can reduce energy consumption.

Influence of the Treatment with Sulfuric Acid on Adhesion of Natural Rubber and Cast Polyurethane Elastomers

2012 ◽  
Vol 452-453 ◽  
pp. 86-90 ◽  
Author(s):  
Zhi Yi Zhang ◽  
Hui Jun Niu ◽  
Jia Jia Zhang ◽  
Yan Yun Cui
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Contact Angle ◽  
Sulfuric Acid ◽  
Natural Rubber ◽  
Angle Measurement ◽  
Polyurethane Elastomers ◽  
Adhesion Properties ◽  
Rubber Surface ◽  
Scanning Electron

In this study, natural rubber (NR) was treated with sulfuric acid to improve its adhesion properties to polar polymer. T-peel strength tests, scanning electron microscopy, contact-angle measurement (water), Energy Dispersive X-ray Detector were used to analyze the nature of the NR surface modifications which were carried out with sulfuric acid. A noticeable decrease in contact angle was observed on the rubber surface by contact-angle measurements which can be ascribed to the increase of oxidized moieties on the rubber surface. EDX revealed that oxidized moieties were created through treatment with sulfuric acid. The surface modification and mode of bond failure were studied by scanning electron microscopy (SEM). Immersion in sulfuric acid for 15min produced the maximum adhesion strength (10kN/m) and produced a mixed failure mode (interface & rubber failure in the rubber). Treatment with sulfuric acid produced improved wettability as well as chemical (surface oxidation) and morphological modifications (roughness) of the rubber surface.

scholarly journals Preparation and Characterization of K-Carrageenan/Nanosilica Biocomposite Film

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Lokesh R. Rane ◽  
Niranjan R. Savadekar ◽  
Pravin G. Kadam ◽  
Shashank T. Mhaske
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Contact Angle ◽  
Tensile Strength ◽  
Water Vapour ◽  
Transmission Rate ◽  
Composite Films ◽  
Tensile Modulus ◽  
Water Vapour Transmission Rate ◽  
Scanning Electron

The purpose of this study is to improve the performance properties of K-carrageenan (K-CRG) by utilizing nanosilica (NSI) as the reinforcing agent. The composite films were prepared by solution casting method. NSI was added up to 1.5% in the K-CRG matrix. The prepared films were characterized for mechanical (tensile strength, tensile modulus, and elongation at break), thermal (differential scanning calorimetry, thermogravimetric analysis), barrier (water vapour transmission rate), morphological (scanning electron microscopy), contact angle, and crystallinity properties. Tensile strength, tensile modulus, and crystallinity were found to have increased by 13.8, 15, and 48% whereas water vapour transmission rate was found to have decreased by 48% for 0.5% NSI loaded K-CRG composite films. NSI was found to have formed aggregates for concentrations above 0.5% as confirmed by scanning electron microscopy. Melting temperature, enthalpy of melting, and degradation temperature of K-CRG increased with increase in concentration of NSI in K-CRG. Contact angle also increased with increase in concentration of NSI in K-CRG, indicating the decrease in hydrophilicity of the films improving its water resistance properties. This knowledge of the composite film could make beneficial contributions to the food and pharmaceutical packaging applications.

The Study of Contamination and Coarsening in Sintering Silicon Powder

2012 ◽  
Vol 557-559 ◽  
pp. 1197-1200
Author(s):  
Jung Ting Tsai ◽  
Cheng Yu Han ◽  
Shung Tian Lin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Vapor Pressure ◽  
Crystalline Structure ◽  
Sintering Temperature ◽  
Silicon Powder ◽  
High Density ◽  
Heat Treated ◽  
Scanning Electron

The goal of this study was to investigate the sintering mechanism of Si powder, with the particle size of Si, sintering temperature, and sintering environment as the variables. The use of a crucible, by controlling the vapor atmosphere at certain temperatures, coarsened the silicon powder. Experiment of data show that by avoiding the vapor pressure of crucible a sintering at 1380°C causes the silicon powder easily to sinter to high density, without the use of any doping addition. Therefore it is to our advantage to discover the microstructure phenomenon of silicon powder and reveal its nature. The crystalline structure of the heat-treated samples was studied with Scanning electron microscopy (SEM) to explain the resultant of contamination that causes the densification.

Super-Hydrophobic Surfaces Improve Corrosion Resistance of Fe3Al-Type Intermetallic in Seawater

2008 ◽  
Vol 47-50 ◽  
pp. 173-176 ◽  
Author(s):  
Tao Liu ◽  
Kin Tak Lau ◽  
Shou Gang Chen ◽  
Sha Cheng ◽  
Yan Sheng Yin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Contact Angle ◽  
Corrosion Resistance ◽  
Electrochemical Impedance ◽  
Hydrophobic Surface ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Atomic Force ◽  
Scanning Electron

A novel super-hydrophobic film was prepared by myristic acid (CH3(CH2)12COOH) chemically adsorbed onto the polyethyleneimine (PEI) coated Fe3Al-type intermetallic wafer. The film character and structure were probed with contact angle measurement, scanning electron microscopy (SEM) and atomic force microscope (AFM). The results suggest that the structure of the film is similar to lotus and the seawater contact angle is larger than 150◦. Moreover, the corrosion resistances of untreated and modified samples in seawater were investigated by electrochemical impedance spectroscopy (EIS). Experimental results show that the corrosion rate of Fe3Al-type intermetallic with super-hydrophobic surface decreases dramatically because of its special microstructure.

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