PHOTOCATALYTIC ACTIVITY OF TiO2 NANO SUPPORTED ON MEMBRANE CELLULOSE ACETATE/NATA DE COCO (CA/NDC) IN PHOTODEGRADATION OF METHYLENE BLUE

2015 ◽  
Vol 11 (1) ◽  
pp. 90
Author(s):  
Roro Ernia Prawithasari ◽  
Ilma Fadilah ◽  
Mudjijono Mudjijono ◽  
Teguh Endah Saraswati ◽  
Dwidjono Hadi Darwanto
Keyword(s):  
Methylene Blue ◽  
Cellulose Acetate ◽  
Particle Diameter ◽  
Inversion Method ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Batch System ◽  
Absorbance Changes ◽  
Phase Inversion Method

<p>Study of synthesis and effectiveness of membrane catalyst of cellulose acetate/nata de coco-TiO<sub>2 </sub>nano (CA/NDC-TiO<sub>2</sub> nano) in photodegradation of methylene blue in batch system has been investigated. TiO<sub>2</sub>nanoparticles were synthesized by hydrothermal method followed by calcination at 450<sup>o</sup>C. Scanning Electron Microscopy (SEM) images indicate nano TiO<sub>2</sub> has been successfully synthesized with average particle diameter as 88,63±4,37 nm.  X-ray diffraction pattern (XRD) of nano TiO<sub>2</sub>  shows some characteristic peaks of anatase TiO<sub>2</sub> were still existed. Membrane photocatalyst of CA/NDC- nano TiO<sub>2</sub> was prepared via phase inversion method by mixing TiO<sub>2</sub> nanoparticles with CA casting solution. Thermogravimetric analysis shows three decomposition steps of CA/NDC-nano membrane as well as CA/NDC membrane. Photodegradation of methylene blue was conducted with nano-TiO<sub>2</sub>  particles and CA/NDC-TiO<sub>2</sub> membrane for 50 minutes in batch system. The absorbance changes were measured by spectrophotometer at wavelength of 664.6 nm. The result shows the photodegradation rections tended to follow second order reaction. According to the rate constant value, <em>k</em>, the photocatalytic effectivity using CA-NDC/nano TiO<sub>2</sub> membrane and nano TiO<sub>2</sub>photocatalysts in metilen blue photodegradation, statistically were not significantly different.</p>

scholarly journals PHOTOCATALYTIC ACTIVITY OF TiO2 NANO SUPPORTED ON MEMBRANE CELLULOSE ACETATE/NATA DE COCO (CA/NDC) IN PHOTODEGRADATION OF METHYLENE BLUE

2016 ◽  
Vol 11 (1) ◽  
pp. 90
Author(s):  
Roro Ernia Prawithasari ◽  
Ilma Fadilah ◽  
Mudjijono Mudjijono ◽  
Teguh Endah Saraswati ◽  
Dwidjono Hadi Darwanto
Keyword(s):  
Methylene Blue ◽  
Cellulose Acetate ◽  
Particle Diameter ◽  
Inversion Method ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Batch System ◽  
Absorbance Changes ◽  
Phase Inversion Method

<p>Study of synthesis and effectiveness of membrane catalyst of cellulose acetate/nata de coco-TiO<sub>2 </sub>nano (CA/NDC-TiO<sub>2</sub> nano) in photodegradation of methylene blue in batch system has been investigated. TiO<sub>2</sub>nanoparticles were synthesized by hydrothermal method followed by calcination at 450<sup>o</sup>C. Scanning Electron Microscopy (SEM) images indicate nano TiO<sub>2</sub> has been successfully synthesized with average particle diameter as 88,63±4,37 nm.  X-ray diffraction pattern (XRD) of nano TiO<sub>2</sub>  shows some characteristic peaks of anatase TiO<sub>2</sub> were still existed. Membrane photocatalyst of CA/NDC- nano TiO<sub>2</sub> was prepared via phase inversion method by mixing TiO<sub>2</sub> nanoparticles with CA casting solution. Thermogravimetric analysis shows three decomposition steps of CA/NDC-nano membrane as well as CA/NDC membrane. Photodegradation of methylene blue was conducted with nano-TiO<sub>2</sub>  particles and CA/NDC-TiO<sub>2</sub> membrane for 50 minutes in batch system. The absorbance changes were measured by spectrophotometer at wavelength of 664.6 nm. The result shows the photodegradation rections tended to follow second order reaction. According to the rate constant value, <em>k</em>, the photocatalytic effectivity using CA-NDC/nano TiO<sub>2</sub> membrane and nano TiO<sub>2</sub>photocatalysts in metilen blue photodegradation, statistically were not significantly different.</p>

Preparation Of Cellulose Acetate Dialysis Membrane Using D–Glucose Monohydrate As Additive

2012 ◽  
Author(s):  
Ani Idris ◽  
Ka Yee Hew ◽  
Mieow Kee Chan
Keyword(s):  
Formic Acid ◽  
Creatinine Clearance ◽  
Cellulose Acetate ◽  
Rejection Rate ◽  
Dissolution Time ◽  
Inversion Method ◽  
Dialysis Membrane ◽  
Sem Images ◽  
Phase Inversion Method ◽  
Bsa Rejection

Dialisis membran yang mengandungi sellulosa asetat (CA) sebagai polimer, asid formik (FA) sebagai pelarut dan glukosa-D monohidrat sebagai bahan tambah telah disediakan melalui proses fasa balikan. Objektif utama bagi penyelidikan ini adalah untuk menyelidik pengaruh bahan tambah glukosa–D terhadap prestasi membran dialisis dari segi pemisahan urea dan kreatinina. Kepekatan glukosa–D diubah daripada 2 hingga 10 wt%. Pemanasan menggunakan ketuhar mikrogelombang yang dapat memendekkan masa pelarutan digunakan untuk melarutkan CA polimer dalam pelarut asid formik. Keputusan menunjukkan bahawa membran yang dihasilkan daripada 20 wt% selulosa asetat, 70 wt% asid formik dan 10 wt% glukosa–D monohidrat memberi prestasi yang terbaik bagi penyingkiran urea and kreatinina sebanyak masing–masimg 49.77% dan 19.54%. Apabila membran yang sama dikaji bagi penahanan BSA, ia memberikan peratus penyingkiran larutan BSA sebanyak 96.78%. Berbanding dengan membran dialisis selulosa asetat komersial, didapati bahawa keputusan adalah memuaskan. Gambar SEM menunjukkan bahawa penambahan glukosa–D monohidrat dalam larutan memberi pembentukan struktur jejari. Kata kunci: Membran dialisis; selulosa asetat; penyingkiran urea; penyingkiran kreatinina; peratus penahanan BSA Dialysis membrane containing cellulose acetate (CA) as polymer, formic acid (FA) as solvent and D–glucose monohydrate as additive was prepared by phase inversion method. The main objective of this study is to investigate the influence of D–glucose monohydrate as an additive on the performance of dialysis membrane in terms of urea and creatinine clearance. The concentration of D–glucose is varied from 2 to 10 wt%. Microwave heating which is capable of reducing dissolution time was used to dissolve the CA polymer in the formic acid solvent. Results revealed that the membrane produced from the 20 wt% cellulose acetate, 70 wt% formic acid and 10 wt% D–glucose monohydrate gives the best performance with urea and creatinine clearance of 49.77% and 19.54% respectively. When testing the same membranes with BSA solutions, it gives a BSA rejection rate as high as 96.78%, which seems to be comparable with the commercial cellulose acetate dialysis membranes. Membrane morphology was observed by using a scanning electron microscopy (SEM). The SEM images illustrated that the increment of D–glucose monohydrate in casting solution tends to promote macrovoid formation. Key words: Dialysis membrane; cellulose acetate; SEM images; urea clearance; creatine clearance; BSA rejection rate

scholarly journals Synthesis and Characterization of Calcium Oxide Nanoparticles from Duck Eggshells using Ball Milling Methods

2019 ◽  
Vol 5 (2) ◽  
pp. 231-135
Author(s):  
Ade Yeti Nuryantini ◽  
Citra Deliana Dewi Sundari ◽  
Halimahtussa’diah Halimahtussa’diah ◽  
Bebeh Wahid Nuryadin
Keyword(s):  
Ball Milling ◽  
Calcium Oxide ◽  
Particle Diameter ◽  
Average Diameter ◽  
Xrd Analysis ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Milling Method ◽  
The Difference

Calcium oxide (CaO) nanoparticles have been successfully synthesized from duck eggshells using ball milling method followed by simple calcination at 700°C for 7 hours. The observation on the morphology, size and shape of the particles of the eggshells powder was conducted through scanning electron microscope (SEM). The milling time was varied, i.e. 2, 6, 10, and 20 hours to observe the difference on the size of the produced particle. SEM images shows that the smallest average particle diameter was 520 nm, achieved by 20 hours of milling. When the particles were calcined, the average diameter was further reduced to 394 nm. The X-ray diffraction (XRD) analysis shows that the resulting particles contain calcium oxide, calcium hydroxide, and calcium carbonate. 

scholarly journals Influence of pretreatment on the properties of α-Fe2O3 and the effect on photocatalytic degradation of methylene blue under visible light

2020 ◽  
Vol 82 (11) ◽  
pp. 2415-2424
Author(s):  
S. Mokhtari ◽  
N. Dokhan ◽  
S. Omeiri ◽  
B. Berkane ◽  
M. Trari
Keyword(s):  
Methylene Blue ◽  
Average Crystallite Size ◽  
Sample Surface ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Lattice Constants ◽  
Electrochemical Pretreatment ◽  
Crystal Properties ◽  
Rhombohedral Symmetry

Abstract The hematite (α-Fe2O3) nanostructures were synthesized by thermal oxidation of metal at 500 °C under atmospheric pressure. We studied the effect of the electrochemical pretreatment of the substrate before calcinations and its impact on the morphology, crystalline structure, lattice microstructural, and optical properties of α-Fe2O3. Uniform nanosheets were observed on the sample surface after calcination; their dimension and morphology were accentuated by the pretreatment, as confirmed by the SEM images. The characteristics of the nanostructures, analyzed by X-ray diffraction (XRD), revealed a rhombohedral symmetry with the space group R-3c and lattice constants: a = 0.5034 nm and c = 1.375 nm. The average crystallite size and strain, determined from the Williamson-Hall (W-H) plot, showed substantial variations after the substrate pretreatment. The Raman spectroscopy confirmed the changes in the crystal properties of the hematite submitted to pretreatment. The diffuse reflectance allowed to evaluate the optical gap which lies between 1.2 and 1.97 eV, induced by the electrochemical processing. The photocatalytic activity of α-Fe2O3 films was assessed by the degradation of methylene blue (MB) under LED light; 15% enhancement of the degradation for the pretreated specimens was noticed.

scholarly journals Comparative Study of Cellulose Hydrogel Films Prepared from Various Biomass Wastes

2021 ◽  
Author(s):  
Cho Cho ◽  
Thinzar Aye ◽  
Aung Khaing ◽  
Takaomi Kobayashi
Keyword(s):  
Biomedical Application ◽  
Cellulose Fibers ◽  
Inversion Method ◽  
X Ray Diffraction ◽  
Biomass Waste ◽  
Waste Products ◽  
Cellulose Hydrogel ◽  
Biomass Materials ◽  
Phase Inversion Method ◽  
Hydrogel Films

The conversion of biomass waste products to valuable products like cellulose hydrogel films is important in cell regeneration. In this study, the various biomass wastes: thanaka heartwood (TH), sugarcane bagasse (SB) and rice straw (RS) were used as cellulose resources. They were chemically treated using acid and alkali to obtain cellulose fibers. The yield percent of cellulose fibers depends on the nature of biomass materials. Scanning Electron Microscope (SEM), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) analyses showed that the amount of lignin and hemicellulose from these samples were successfully reduced by chemical treatment. Cellulose fibers were treated using the dimethylacetamide/lithium chloride (DMAc/LiCl) system to obtain cellulose hydrogel solutions. Following this, the cellulose hydrogel films were prepared employing the phase inversion method without cross-linker. These films were transparent and flexible. In the present study, water retainable property and viscoelasticity of cellulose hydrogel films were measured. Antimicrobial activity tests of cellulose solutions have been carried out to be utilized to hydrogel films for biomedical application.

scholarly journals Removal of hexavalent chromium from graphene oxide supported on a cellulose acetate and polyacrylic acid membrane

2021 ◽  
pp. 1-8
Author(s):  
Juan SÁNCHEZ-MÁRQUEZ ◽  
Rosalba FUENTES-RAMÍREZ ◽  
Zeferino GAMIÑO-ARROYO
Keyword(s):  
Graphene Oxide ◽  
Cellulose Acetate ◽  
Hexavalent Chromium ◽  
Polyacrylic Acid ◽  
Contact Time ◽  
Polymeric Membrane ◽  
Point Of Zero Charge ◽  
Inversion Method ◽  
Initial Concentration ◽  
Phase Inversion Method

This work focused on the study of the hexavalent chromium removal process from graphene oxide supported on a cross-linked cellulose acetate and polyacrylic acid polymeric membrane. The membranes were synthesized by the phase inversion method and Graphene oxide was added in proportions of 1% by weight to the polymeric material. Graphene oxide was obtained from crystalline graphite (Electron Microscope Science, No. 70230). The graphite was oxidized using the improved method of Hummers. The characterization of polymer and graphene oxide was made by Raman spectroscopy. The surface charge and point of zero charge of the materials were evaluated using a potentiometric titration method proposed by Loskutov and Kuzin. The removal of Cr (VI) was studied as a function of contact time and of initial concentration of Cr (VI). The removal of Cr (VI) (~90%) mainly occurs in a contact time from 32 to 64 h when the initial concentration of Cr (VI) is 1 mg/L.

The Effect of Synthetic Silica on Ultrafiltration PSf Membrane

2013 ◽  
Vol 65 (4) ◽  
Author(s):  
Zawati Harun ◽  
Mohd Riduan Jamalludin ◽  
Hatijah Basri ◽  
Muhamad Fikri Shohur ◽  
Nurafiqah Rosman ◽  
...  
Keyword(s):  
Pure Water ◽  
Water Flux ◽  
Inversion Method ◽  
X Ray Diffraction ◽  
Weight Percentage ◽  
Pure Water Flux ◽  
Dope Solution ◽  
And Performance ◽  
Polyethelene Glycol ◽  
Phase Inversion Method

This study investigates the effects of synthetic silica(SiO2)with different weight percentage concentrations on the morphology and performance of the polysulfone (PSf) and polyethelene glycol (PEG) based membrane ultrafiltration (UF). Phase inversion method was used to prepare PSf/PEG ultrafiltration (UF) flatsheet membrane. SiO2 and N-Methyl 2 Pyrrolidone (NMP) were used as an additive and solvent respectively. The fabricated membrane was characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and the performances of the membranes were measured in term of pure water flux by using distilled water and solute rejection at different wastewater concentration at 50%, 75% and 87.5%. The result showed that the addition of 2% silica in the dope solution increased the permeation in terms pure water flux and the best rejection with 62 Lm-2 h-1 and 89% (at 87.5 % waste water dilution) respectively

Preparation of Nanocomposite Fluid by Electrical Arc Discharge Technique

2008 ◽  
Vol 8 (2) ◽  
pp. 936-943
Author(s):  
Ho Chang
Keyword(s):  
Heat Transfer ◽  
Arc Discharge ◽  
Particle Diameter ◽  
Electric Arc ◽  
Heat Transfer Analysis ◽  
Process Conditions ◽  
Average Particle ◽  
Sem Images ◽  
Discharge System ◽  
Electrical Arc

This study proposes a new method, the electrical arc discharge system, for preparing a nanocomposite fluid with the basic ingredients of Cu, Fe and O. The proposed system has the advantages of a high-power electric arc heating system, excellent stability of the electric arc, and well-developed control technology. In the fabrication process, the positive electrode uses a copper rod and the negative electrode an iron rod, and the two electrodes are processed in the insulating processing liquid. The nanocomposite fluid generated by the synthesis system is analyzed by morphological analysis, heat transfer analysis, magnetism analysis, and rheological testing. The experiment generates satisfactory results for nanocomposite fluid with an average particle diameter of 25 nm by process conditions of vacuum pressure of 30 torr, peak current of 7 A for arc discharge, breakdown voltage of 250 V and duration time of 10 μs. The experimental results showed that the nanocomposite fluid is composed of Fe, FeO, Cu, and Cu2O. SEM images show that Fe and Cu are spherical, FeO is square, and Cu2O is ovoid. For the heat transfer experiment, the experimental temperature was set at ambient temperature of 30 °C, the average heat transfer coefficient is 0.708 W/m °C, which is 16.3% higher than that of deionized water. The magnetism test shows that the magnetic retentivity of the fluid is 47.27 (Oe), which makes it a soft magnetic fluid.

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