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 Biofilm Inhibition and Antimicrobial Properties of Silver-Ion-Exchanged Zeolite A against Vibrio spp Marine Pathogens

2021 ◽  
Vol 11 (12) ◽  
pp. 5496
Author(s):  
Zarina Amin ◽  
Nur Ariffah Waly ◽  
Sazmal Effendi Arshad
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Antimicrobial Properties ◽  
Immune Defense ◽  
Silver Ion ◽  
Bacterial Disease ◽  
Zeolite A ◽  
Biofilm Inhibition ◽  
Volcanic Origin ◽  
Scanning Electron

A challenging problem in the aquaculture industry is bacterial disease outbreaks, which result in the global reduction in fish supply and foodborne outbreaks. Biofilms in marine pathogens protect against antimicrobial treatment and host immune defense. Zeolites are minerals of volcanic origin made from crystalline aluminosilicates, which are useful in agriculture and in environmental management. In this study, silver-ion-exchanged zeolite A of four concentrations; 0.25 M (AgZ1), 0.50 M (AgZ2), 1.00 M (AgZ3) and 1.50 M (AgZ4) were investigated for biofilm inhibition and antimicrobial properties against two predominant marine pathogens, V. campbelli and V. parahemolyticus, by employing the minimum inhibitory concentration (MIC) and crystal violet biofilm quantification assays as well as scanning electron microscopy. In the first instance, all zeolite samples AgZ1–AgZ4 showed antimicrobial activity for both pathogens. For V. campbellii, AgZ4 exhibited the highest MIC at 125.00 µg/mL, while for V. parahaemolyticus, the highest MIC was observed for AgZ3 at 62.50 µg/mL. At sublethal concentration, biofilm inhibition of V. campbelli and V. parahemolyticus by AgZ4 was observed at 60.2 and 77.3% inhibition, respectively. Scanning electron microscopy exhibited profound structural alteration of the biofilm matrix by AgZ4. This is the first known study that highlights the potential application of ion-exchanged zeolite A against marine pathogens and their biofilms.

Toughened Chitosan Composite Nanofiltration Membrane by Introduction of Acrylic Acid

2019 ◽  
Vol 815 ◽  
pp. 139-144
Author(s):  
Tao Mu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Tensile Strength ◽  
Acrylic Acid ◽  
Nanofiltration Membrane ◽  
Modified Chitosan ◽  
Atomic Force ◽  
Infrared Spectrophotometer ◽  
Chitosan Composite ◽  
Scanning Electron

In this paper, acrylic acid was grafted to chitosan in order to change the structure; polymer was obtained from modified chitosan. A series of novel toughened composite NF memebranes were prepared by over-coating the polysulfone ultrafiltration membrane with the polymer of modified chitosan. The chitosan derivatives and the polymer were characterised by infrared spectrophotometer (IR); the structure of the membrane was characrerised by scanning electron microscopy (SEM) and atomic force microscope (AFM). The composite NF membrane’s performances were strictly related to the structure of polymer. The rejection of the membrane was 96.3% with flux as high as 386.46 L m-2 h-1 with the 1000 mg/L of NaCl. Tensile strength of membrane increased 46%. The HCl (5%) resistance increased from 20.3 to 36.8h. The NaOH (5%) resistance increased from 18.3 to 31.6h. These results indicated the prepared toughened composite NF memebrane was excellent NF membrane, which had a wide application prospect.

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.

scholarly journals Synthesis of Zeolite A employing Amazon kaolin waste

Cerâmica ◽  
2015 ◽  
Vol 61 (360) ◽  
pp. 409-413 ◽  
Author(s):  
S. H. da Silva Filho ◽  
L. Bieseki ◽  
A. R. da Silva ◽  
A. A. B. Maia ◽  
R. A. S. San Gil ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Amorphous Materials ◽  
Mas Nmr ◽  
The Other ◽  
Zeolite A ◽  
X Ray Diffraction ◽  
X Ray ◽  
27Al Mas Nmr ◽  
Scanning Electron

Abstract The synthesis of zeolite A employing kaolin waste from paper coating was studied. The kaolin waste was pre-treated at 550 to 800 ºC. For comparison purposes, a sample of zeolite A was also prepared using the IZA procedure. The materials were characterized by 27Al MAS NMR, X-ray diffraction and scanning electron microscopy using a microprobe. Pretreatment was necessary, and the best temperatures were between 600 and 700 ºC. The zeolite A formation was observed in all the prepared materials, reaching 52% crystallinity. On the other hand, the sodalite phase and amorphous materials were also formed.

scholarly journals Biofilm Inhibition and Antimicrobial Properties of Silver Ion-Exchanged Zeolite a against Vibrio spp Marine Pathogens

2021 ◽  
Author(s):  
Zarina Amin ◽  
SAZMAL EFFENDI ARSHAD ◽  
NUR ARIFAH WALY
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Antimicrobial Properties ◽  
Antimicrobial Treatment ◽  
Silver Ion ◽  
Bacterial Disease ◽  
Zeolite A ◽  
Biofilm Inhibition ◽  
Volcanic Origin ◽  
Scanning Electron

A challenging problem in the aquaculture industry is bacterial disease outbreaks which results in the global reduction of fish supply and foodborne outbreaks. Biofilms in marine pathogens protect against antimicrobial treatment and host immune defence. Zeolites are minerals of volcanic origin made from crystalline aluminosilicates which are useful in agriculture and in environmental management. In this study, silver ion-exchanged zeolite A of four concentrations; 0.25M (AgZ1), 0.50M (AgZ2), 1.00M (AgZ3)and 1.50M (AgZ4) were investigated for biofilm inhibition and antimicrobial properties against two predominant marine pathogens V. campbelli and V. parahemolyticus by employing the Minimum Inhibitory Concentration(MIC), Crystal Violet Biofilm Quantification assays as well as Scanning Electron Microscopy. In the first instance, all zeolite samples AgZ1-AgZ4 showed antimicrobial activity for both pathogens. For V. campbellii AgZ4 exhibited the highest MIC at 125.00 µg/ml while for V. parahaemolyticus the highest MIC was observed for AgZ3 at 62.50 µg/ml. At sublethal concentration, biofilm inhibition of V. campbelli and V. parahemolyticus by AgZ4 were observed at 60.2% and 77.3% inhibition respectively. Scanning electron microscopy exhibited profound structural alteration of the biofilm matrix by AgZ4. This is the first known study that highlights the potential application of ion-exchanged Zeolite A against marine pathogens and their biofilms.

Organophilic Modification and Application of Nano-Fumed Silica in Pervaporation of Ethanol / Water Mixture

2011 ◽  
Vol 117-119 ◽  
pp. 679-682
Author(s):  
Bing Bing Li ◽  
Liang Wang ◽  
De Sun
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fourier Transform ◽  
Fumed Silica ◽  
Water Mixture ◽  
Transmission Electron ◽  
Ft Ir ◽  
Scanning Electron ◽  
Better Than

Fumed Silica was modified with hexamethyldisiazane (HMDZ, modifier) and dimethyldiethoxysilane (DMDEOS, co-modifier) by grafting method. The structure of organo-functionnalized nanoparticles was characterized by fourier transform infrared spectrum (FT-IR) and transmission electron microscopy (TEM). Functional nanosilica-filled polydimethylsiloxane(PDMS) composites membrane were prepared. Scanning electron microscopy (SEM) observations of composites revealed good dispersion of the silica nanoparticles and the pervaporation performance of the filled PDMS membranes is better than that of the unfilled PDMS membranes.

Hydrothermal Synthesis of Zeolite a Using Non-Calcined Diatomite

2018 ◽  
Vol 930 ◽  
pp. 3-7 ◽  
Author(s):  
Alexandre Fontes Melo de Carvalho ◽  
Tiago Roberto da Costa ◽  
Gilvan Pereira de Figueredo ◽  
José Antônio Barros Leal Reis Alves ◽  
Rodrigo César Santiago ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Hydrothermal Synthesis ◽  
Crystallite Size ◽  
Powder Diffraction ◽  
Average Crystallite Size ◽  
Zeolite A ◽  
X Ray ◽  
Prepared Sample ◽  
Scanning Electron

Optimization and reduction of zeolite A synthesis costs are the focus of several studies. Attention has been given to the use of residues and natural materials rich in Si and Al, such as diatomite. Diatomite needs to be calcined above 500°C to be used, which increases processing costs. This study aimed at evaluating the use of diatomite without calcination in preparing zeolite A. Alkaline hydrothermal synthesis melting and 24 h of crystallization were carried out. The materials were characterized by XRD (X-ray powder diffraction), XRF (X-ray fluorescence), BET (N2physisorption) and SEM (Scanning Electron Microscopy). XRD data and refinement show that the obtained material presents 99.84% crystallinity, average crystallite size of 54.92 nm, and a semi-quantitative percentage of 79% zeolite A. SiO2and Al2O3contents in the prepared sample proved the ratio SiO2/Al2O3= 2. The micrographies show cubic particles and agglomerated sodalite.

scholarly journals Membran nonofiltrasi untuk penghilangan ion valensi tinggi dan senyawa organik dari sumber air salinitas tinggi

2018 ◽  
Vol 5 (3) ◽  
pp. 478 ◽  
Author(s):  
Iman Ciptaraharja ◽  
Veronica S. Praptowidodo
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cellulose Acetate ◽  
Reverse Osmosis ◽  
Cellulose Acetate Membrane ◽  
Operating Pressure ◽  
Nanofiltration Membrane ◽  
Feed Concentration ◽  
Porous Support ◽  
Scanning Electron

Utilization of nanofiltration membrane for high valence ion and organic compound removing from high salinized water source.The influence of solvent selection to membrane morphology for cellulose acetate nanofiltration membrane preparation in mass transfer of a multistage reverse osmosis process is studied. Membrane is prepared via precipitation immersion technique. The polymer used in this study is cellulose acetate (CA) with a concentration of 25 %-w. The feed concentration of univalent ion solution (NaCl) is varied between 2000-16.000 mg/L. The operating pressure is adjusted such that the operating pressure is three times of the osmotic pressure of NaCl solution. The concentration of bivalent ion (CaCl2), trivalent ion (FeCl3), and organic substance (glucose) are 200 mg/L, 50 mg/L, and 100 mg/L, respectively. The morphology of the membrane is characterized using Scanning Electron Microscopy (SEM). Membrane CA-01 (CA/DMF/Water) is a nanofiltration membrane with a thinner active layer and a more porous support layer than membrane CA-02 (CA/Aceton/Watter) which is categorized as a reverse osmosis membrane. A reduced feed concentration (at a fixed operating pressure) gives an elevated flux however the rejection is decreased. Meanwhile, an elevated operating pressure (at a fixed feed concentration) gives an elevated flux and rejection. Membrane CA-01 has met the requirement as a nanofiltration membrane since it gives 66 % rejection for NaCl at 20 Bar. At the same operating pressure, membrane CA-01 gives rejection for CaCl2, FeCl3, and glucose of 80.45%, 82.14%, and 83.42%, respectively.Keywords: Cellulose Acetate, Membrane, Multistage, Nanotiltration, Reverse Osmosis, Saline WaterAbstrakPenelitian ini dilakukan untuk mempelajari pengaruh jenis pelarut dalam pembuatan membran nanofiltrasi dari polimer selulosa asetat terhadap struktur morfologi membran dalam peristiwa perpindahan massa pada proses pemisalan osmosis balik multitahap. Teknik pembuatan membran yang digunakan adalah presipitasi imersi. Polimer membran yang digunakan adalah seulosa asetat (CA) pada konsentrasi 25 %-berat. Umpan yang digunakan adalah larutan ion valensi satu (NaCl) dengan variasi konsentrasi antara 2000 hingga 16.000 mg/L. Tekanan operasi diatur sedemikian rupa sehingga nilai rekanan operasi adalah sekitar tiga kali tekanan osmotik larutan NaCl. Percobaan juga dilakukan untuk umpan larutan ion valensi dua (CaCl2), ion valensi tiga (FeCl3), dan senyawa organik (glukosa) dengan konsentrasi, berturut-turut, adalah 200 mg/L, 50 mg/L,  dan 100 mg/L. Struktur morfologi membran diuji menggunakan metoda Scanning Electron Microscopy (SEM). Membran CA-01 (CA/DMF/Air) merupakan membran nanofiltrasi dengan lapisan aktif yang lebih tipis dan ukuran pori lapisan penyangga yang lebih besar daripada membran CA-02 (CA/Aseton/Air), yang termasuk ke dalam membran osmosis balik. Penurunan konsentrasi umpan pada tekanan operasi yang tetap memberikan nilai fluks yang meningkat, namun memberikan nilai rejeksi yang menurun. Sementara itu, peningkatan tekanan operasi pada konsentrasi umpan yang tetap akan memberikan nilai fluks dan rejeksi yang meningkat. Membran CA-01 telah memenuhi persyaratan sebagai membran nanofiltrasi dengan rejeksi NaCl mencapai 66 % pada tekanan 20 Bar. Pada tekanan yang sama membran CA-01 memberikan nilai rejeksi untuk CaCl2, FeCl3, dan glukosa berturut-turut sebesar 80,45%, 82,14%, dan 83,42 %.Kata Kunci: Air Salinitas Tinggi, Membran, Multitahap, Nanofiltrasi, Osmosis Balik, Selulosa Asetat.

Multi-Cycle Photodegradation of Anionic and Cationic Dyes by New TiO2/DSAT Immobilization System

2016 ◽  
Vol 835 ◽  
pp. 353-358 ◽  
Author(s):  
Wan Izhan Nawawi ◽  
S.K. Ain ◽  
R. Zaharudin ◽  
Sudirman Sahid
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Methylene Blue ◽  
Photocatalytic Performance ◽  
Glass Plate ◽  
Sem Analysis ◽  
Adhesive Tape ◽  
Support Material ◽  
Reactive Red 4 ◽  
Scanning Electron

In this work, titanium dioxide (TiO2) photocatalyst was generally immobilized onto glass plate support material by employing double sided adhesive tape (DSAT) as a thin layer binder. The photocatalytic performance of this new non-additive immobilization system was observed under the degradation of two different charges of dyes namely anionic reactive red 4 (RR4) and cationic methylene blue (MB) dyes. Photocatalytic degradation of RR4 and MB dyes under immobilized TiO2/DSAT were compared with TiO2 in suspension mode respectively. Immobilized TiO2/DSAT was observed to have up to 30 cycles of reusability thanks to DSAT that is able to provide a very strong intact between the glass plate and TiO2 layers. In fact, a better photodegradation activity was observed by number of photocatalysis cycles due to increasing pores formation on TiO2 surface as observed by Scanning Electron Microscopy (SEM) analysis.

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