scholarly journals Micelle-Assisted Synthesis of Al2O3·CaO Nanocatalyst: Optical Properties and Their Applications in Photodegradation of 2,4,6-Trinitrophenol

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Ayesha Imtiaz ◽  
Muhammad Akhyar Farrukh ◽  
Muhammad Khaleeq-ur-rahman ◽  
Rohana Adnan
Keyword(s):  
Particle Size ◽  
Calcium Oxide ◽  
Optical Band Gap ◽  
Sodium Dodecyl ◽  
Unique Property ◽  
Precipitation Method ◽  
High Adsorption ◽  
Templating Agent ◽  
Good Catalytic Activity ◽  
High Adsorption Capacity

Calcium oxide (CaO) nanoparticles are known to exhibit unique property due to their high adsorption capacity and good catalytic activity. In this work the CaO nanocatalysts were prepared by hydrothermal method using anionic surfactant, sodium dodecyl sulphate (SDS), as a templating agent. The as-synthesized nanocatalysts were further used as substrate for the synthesis of alumina doped calcium oxide (Al2O3·CaO) nanocatalysts via deposition-precipitation method at the isoelectric point of CaO. The Al2O3·CaO nanocatalysts were characterized by FTIR, XRD, TGA, TEM, and FESEM techniques. The catalytic efficiencies of these nanocatalysts were studied for the photodegradation of 2,4,6-trinitrophenol (2,4,6-TNP), which is an industrial pollutant, spectrophotometrically. The effect of surfactant and temperature on size of nanocatalysts was also studied. The smallest particle size and highest percentage of degradation were observed at critical micelle concentration of the surfactant. The direct optical band gap of the Al2O3·CaO nanocatalyst was found as 3.3 eV.

scholarly journals Investigating the Feasibility of Mefenamic Acid Nanosuspension for Pediatric Delivery: Preparation, Characterization, and Role of Excipients

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 574
Author(s):  
Nikhat Perween ◽  
Sultan Alshehri ◽  
T. S. Easwari ◽  
Vivek Verma ◽  
Md. Faiyazuddin ◽  
...  
Keyword(s):  
Particle Size ◽  
Mefenamic Acid ◽  
Hydroxypropyl Methylcellulose ◽  
Sodium Dodecyl ◽  
Aqueous Solubility ◽  
Oral Route ◽  
Precipitation Method ◽  
Antisolvent Precipitation

Molecules with poor aqueous solubility are difficult to formulate using conventional approaches and are associated with many formulation delivery issues. To overcome these obstacles, nanosuspension technology can be one of the promising approaches. Hence, in this study, the feasibility of mefenamic acid (MA) oral nanosuspension was investigated for pediatric delivery by studying the role of excipients and optimizing the techniques. Nanosuspensions of MA were prepared by adopting an antisolvent precipitation method, followed by ultrasonication with varying concentrations of polymers, surfactants, and microfluidics. The prepared nanosuspensions were evaluated for particle size, morphology, and rheological measures. Hydroxypropyl methylcellulose (HPMC) with varying concentrations and different stabilizers including Tween® 80 and sodium dodecyl sulfate (SLS) were used to restrain the particle size growth of the developed nanosuspension. The optimized nanosuspension formula was stable for more than 3 weeks and showed a reduced particle size of 510 nm with a polydispersity index of 0.329. It was observed that the type and ratio of polymer stabilizers were responsive on the particle contour and dimension and stability. We have developed a biologically compatible oral nanoformulation for a first-in-class drug beautifully designed for pediatric delivery that will be progressed toward further in vivo enabling studies. Finally, the nanosuspension could be considered a promising carrier for pediatric delivery of MA through the oral route with enhanced biological impact.

Hydrogen Sulfide Separation from Biogas Using Laterite Soil Adsorbent

2020 ◽  
Vol 988 ◽  
pp. 144-150
Author(s):  
Sanggono Adisasmito ◽  
Carolus Borromeus Rasrendra ◽  
M. Qori Alfadhli ◽  
M. Fauzan Al Ghifary
Keyword(s):  
Particle Size ◽  
Adsorption Capacity ◽  
Room Temperature ◽  
Biogas Production ◽  
Separation Process ◽  
High Adsorption ◽  
Laterite Soil ◽  
Adsorption Column ◽  
Bed Height ◽  
High Adsorption Capacity

Biogas production contributes as an alternative renewable energy but its emissions contain sulphuric components which needs to be separated because it can cause damage to the environment. The method used in separation is adsorption with laterite soil because the price is cheap, easy to obtain, and can occur at room temperature. The purpose of this study is to determine the conditions of the adsorbent in the adsorption column which can provide a high adsorption capacity. The separation process is carried out by flowing biogas with a flow rate of 1.5 liters/minute to the adsorption column containing laterite soil. Reducing the particle size of the adsorbent from 6 mesh to 21 mesh will increase the adsorption capacity to 2.13 times, ie from 7.3 to 14.2 mg H2S/g adsorbent. The addition of bed height from 7 cm to 12 cm will increase the adsorption capacity from 6.7 to 7.9 mg H2­S/g adsorbent at 6 mesh particle size. The addition of bed height from 7 cm to 12 cm will increase the adsorption capacity from 13.5 to 15.0 mg H2S/g adsorbent at 21 mesh particle size. The laterite soil adsorbent with a particle size of 21 mesh has the highest adsorption capacity of 15.0 mg H2S/g adsorbent.

Ga-Modified Nanostructured ZnO: Characterization and Application in Dye-Sensitized Solar Cells

2008 ◽  
Vol 591-593 ◽  
pp. 13-17
Author(s):  
Agnaldo S. Gonçalves ◽  
Ana Flavia Nogueira ◽  
Marian R. Davolos ◽  
Naruhiko Masaki ◽  
Shozo Yanagida ◽  
...  
Keyword(s):  
Particle Size ◽  
Optical Properties ◽  
Solar Cells ◽  
Band Gap ◽  
Optical Band Gap ◽  
Dye Sensitized Solar Cells ◽  
Binding Energies ◽  
Precipitation Method ◽  
Dye Sensitized ◽  
Sensitized Solar Cells

ZnO has received great attention in many applications due to its electronic and optical properties. We report on the preparation of ZnO and gallium-containing ZnO (ZnO:Ga) nanoparticles by the precipitation method. The nanoparticles have the wurtzite structure and a high crystallinity. Gallium ions are present as Ga3+, as evidenced by the binding energies through XPS. Porosity and surface area of the powder increased under increasing gallium level, explained by the smaller particle size of ZnO:Ga samples compared with ZnO. The estimated optical band gap of ZnO was 3.2 eV, comparable to ZnO:Ga.

scholarly journals Investigating the adsorption of cesiun ion (Cs+) on cobalt hexacyanoferrate coated magnetite nanoparticles

2020 ◽  
Vol 2 (6) ◽  
pp. 192-200
Author(s):  
Nguyen Dinh Trung ◽  
Le Thi Ha Lan ◽  
Nguyen Thi My Ngoc ◽  
Nguyen An Son
Keyword(s):  
Ion Exchange ◽  
Exchange Capacity ◽  
Precipitation Method ◽  
Fe3o4 Nanoparticle ◽  
High Adsorption ◽  
Ion Exchange Capacity ◽  
Freundlich Isotherms ◽  
Cobalt Hexacyanoferrate ◽  
High Adsorption Capacity ◽  
Co Precipitation

Co2[Fe(CN)6]/Fe3O4 nanoparticle adsorbent for ion cesium (Cs+) sorption was prepared by a chemical co-precipitation method. The magnetization of the materials makes them to be separated easyly from an aqueous solution by an external magnetic field. The ion Cs+ absorption by Co2[Fe(CN)6]/Fe3O4 nanoparticle follow the ion exchange mechanism, ion exchange capacity depends on the pH, the maximum ion exchange capacity of the material at pH = 4 is 0.40 meq (Cs+)/ g. After 15 min, about 98% of initial ion Cs+ concentration was removed from the solution, the adsorption could be described by Langmuir and Freundlich isotherms. The high adsorption capacity and good performance on other aspects, make the Co2[Fe(CN)6]/Fe3O4 nanoparticle a promissing adsorbent for the removal of ion Cs+ from water.

scholarly journals Sintesis dan Karakterisasi Nanokalsium Oksida dari Cangkang Telur

2020 ◽  
Vol 16 (2) ◽  
pp. 250
Author(s):  
Sunardi Sunardi ◽  
Erlynda Desy Krismawati ◽  
Argoto Mahayana
Keyword(s):  
Particle Size ◽  
Calcium Oxide ◽  
Calcium Deficiency ◽  
The Body ◽  
Precipitation Method ◽  
Synthesis And Characterization ◽  
Elemental Content ◽  
Oxide Crystals ◽  
Nano Size

<p>Pencegahan osteoporosis dilakukan dengan mengkonsumsi kalsium. Pada umumnya kalsium yang dikonsumsi dalam bentuk mikro kalsium. Ukuran mikro kalsium hanya diserap tubuh sekitar 50%, sehingga sering menyebabkan defisiensi. Sehingga, teknologi untuk membuat ukuran nanokalsium telah dikembangkan agar penyerapan kalsium dalam tubuh lebih besar. Penelitian ini bertujuan untuk mensintesis nanokalsium dari cangkang telur yang merupakan limbah industri roti. Sintesis nanokalsium oksida dari cangkang telur dengan metode presipitasi. Sintesis dilakukan dengan mereaksikan cangkang telur yang telah bersih dan kering dengan HCl 2 N. Hasil reaksi dipisahkan dengan penyaringan sehingga diperoleh filtrat. Filtrat yang diperoleh direaksikan dengan NaOH sampai pengendapan tidak terbentuk lagi. Endapan yang diperoleh kemudian dipisahkan, dioven, dan dibakar dalam tanur pada suhu 600 °C selama 1 jam. Serbuk hasil sintesis dikarakterisasi menggunakan SEM-EDX, XRD dan FTIR. Hasil penelitian menunjukkan bahwa cangkang telur dapat disintesis menjadi nanokalsium oksida berupa kristal berwarna putih. Karakterisasi menggunakan SEM-EDX diperoleh hasil bahwa nanokalsium oksida dari cangkang telur berbentuk speris, teraglomerasi dengan ukuran partikel 12,41582 ± 0,13961 nm, mengandung unsur yaitu O (55,83%), C (33,24%), dan Ca (10,94%). Karakterisasi dengan XRD menunjukkan bahwa ukuran kristal nanokalsium oksida diperoleh hasil sebesar 10,46 nm. Karakterisasi dengan FTIR diperoleh puncak pada bilangan gelombang 1477,54 cm-1, 1053,15 cm-1, 8863,68 cm-1 dan ikatan Ca-O pada bilangan gelombang 512 cm-1.</p><p><strong>Synthesis and Characterization of Nano-Calcium Oxide from Eggshells. </strong>Consumption of calcium can prevent osteoporosis. Usually, calcium is consumed in the form of micro calcium. The micro size calcium is only absorbed by the body at around 50%, causing calcium deficiency. Therefore, technology to produce nano-size calcium has been developed to increase the amount of adsorption. This study aims to synthesize nano calcium from eggshells as a solid waste of bread industries. The synthesis was conducted by precipitation method. The synthesis was carried out by reacting clean and dry eggshells with HCl 2 N, and then followed by filtering to obtain the filtrate. The filtrate obtained was reacted with NaOH until the calcium was precipitated. The precipitate obtained was then separated, roasted, and burned in a furnace at 600 °C for 1 hour. The synthesized powders were characterized using SEM-EDX, XRD, and FTIR. The results showed that eggshells could be synthesized into nano-calcium oxide in the form of white crystals. Characterization using SEM-EDX showed that nano-calcium oxide from spherical eggshells, agglomerated with the particle size of 12.41582 ± 0.13961 nm, with elemental content of O (55.83%), C (33.24%), and Ca (10.94%). Characterization with XRD shows that the size of nano calcium oxide crystals was 10.46 nm. Characterization with FTIR shows peak at wavenumbers 1477.54 cm<sup>-1</sup>, 1053.15 cm<sup>-1</sup>, 8863.68 cm<sup>-1</sup>, and the Ca-O bond reveals at 512 cm<sup>-1</sup>.</p><strong></strong>

scholarly journals Sintesis dan Karakterisasi Nanokalsium Oksida dari Cangkang Telur

2020 ◽  
Vol 16 (2) ◽  
pp. 99
Author(s):  
Sunardi Sunardi ◽  
Erlynda Desy Krismawati ◽  
Argoto Mahayana
Keyword(s):  
Particle Size ◽  
Calcium Oxide ◽  
Calcium Deficiency ◽  
The Body ◽  
Precipitation Method ◽  
Synthesis And Characterization ◽  
Elemental Content ◽  
Oxide Crystals ◽  
Nano Size

<p>Pencegahan osteoporosis dilakukan dengan mengkonsumsi kalsium. Pada umumnya kalsium yang dikonsumsi dalam bentuk mikro kalsium. Ukuran mikro kalsium hanya diserap tubuh sekitar 50%, sehingga sering menyebabkan defisiensi. Sehingga, teknologi untuk membuat ukuran nanokalsium telah dikembangkan agar penyerapan kalsium dalam tubuh lebih besar. Penelitian ini bertujuan untuk mensintesis nanokalsium dari cangkang telur yang merupakan limbah industri roti. Sintesis nanokalsium oksida dari cangkang telur dengan metode presipitasi. Sintesis dilakukan dengan mereaksikan cangkang telur yang telah bersih dan kering dengan HCl 2 N. Hasil reaksi dipisahkan dengan penyaringan sehingga diperoleh filtrat. Filtrat yang diperoleh direaksikan dengan NaOH sampai pengendapan tidak terbentuk lagi. Endapan yang diperoleh kemudian dipisahkan, dioven, dan dibakar dalam tanur pada suhu 600 °C selama 1 jam. Serbuk hasil sintesis dikarakterisasi menggunakan SEM-EDX, XRD dan FTIR. Hasil penelitian menunjukkan bahwa cangkang telur dapat disintesis menjadi nanokalsium oksida berupa kristal berwarna putih. Karakterisasi menggunakan SEM-EDX diperoleh hasil bahwa nanokalsium oksida dari cangkang telur berbentuk speris, teraglomerasi dengan ukuran partikel 12,41582 ± 0,13961 nm, mengandung unsur yaitu O (55,83%), C (33,24%), dan Ca (10,94%). Karakterisasi dengan XRD menunjukkan bahwa ukuran kristal nanokalsium oksida diperoleh hasil sebesar 10,46 nm. Karakterisasi dengan FTIR diperoleh puncak pada bilangan gelombang 1477,54 cm-1, 1053,15 cm-1, 8863,68 cm-1 dan ikatan Ca-O pada bilangan gelombang 512 cm-1.</p><p><strong>Synthesis and Characterization of Nano-Calcium Oxide from Eggshells. </strong>Consumption of calcium can prevent osteoporosis. Usually, calcium is consumed in the form of micro calcium. The micro size calcium is only absorbed by the body at around 50%, causing calcium deficiency. Therefore, technology to produce nano-size calcium has been developed to increase the amount of adsorption. This study aims to synthesize nano calcium from eggshells as a solid waste of bread industries. The synthesis was conducted by precipitation method. The synthesis was carried out by reacting clean and dry eggshells with HCl 2 N, and then followed by filtering to obtain the filtrate. The filtrate obtained was reacted with NaOH until the calcium was precipitated. The precipitate obtained was then separated, roasted, and burned in a furnace at 600 °C for 1 hour. The synthesized powders were characterized using SEM-EDX, XRD, and FTIR. The results showed that eggshells could be synthesized into nano-calcium oxide in the form of white crystals. Characterization using SEM-EDX showed that nano-calcium oxide from spherical eggshells, agglomerated with the particle size of 12.41582 ± 0.13961 nm, with elemental content of O (55.83%), C (33.24%), and Ca (10.94%). Characterization with XRD shows that the size of nano calcium oxide crystals was 10.46 nm. Characterization with FTIR shows peak at wavenumbers 1477.54 cm<sup>-1</sup>, 1053.15 cm<sup>-1</sup>, 8863.68 cm<sup>-1</sup>, and the Ca-O bond reveals at 512 cm<sup>-1</sup>.</p><strong></strong>

Mercury Removal from Wastewater by Steamed Hoof Powder

1999 ◽  
Vol 40 (7) ◽  
pp. 109-116 ◽  
Author(s):  
M. H. Ansari ◽  
A. M. Deshkar ◽  
P. S. Kelkar ◽  
D. M. Dharmadhikari ◽  
M. Z. Hasan ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Adsorption Capacity ◽  
Adsorption Process ◽  
Adsorption Equilibrium ◽  
Light Metal ◽  
Mercury Removal ◽  
High Adsorption ◽  
Surface Sites ◽  
Ph Values ◽  
High Adsorption Capacity

Steamed Hoof Powder (SHP), size &lt; 53μ, was observed to have high adsorption capacity for Hg(II) with &gt;95% removal from a solution containing 100 mg/L of Hg(II) with only 0.1% (W/V) concentration of SHP. The SHP has good settling properties and gives clear and odour free effluent. Studies indicate that pH values between 2 and 10 have no effect on the adsorption of Hg(II) on SHP. Light metal ions like Na+, K+, Ca2+ and Mg2+ up to concentrations of 500 mg/L and heavy metals like Cu2+, Zn2+, Cd2+, Co2+, Pb2+, Ni2+, Mn2+, Cr3+, Cr6+, Fe2+ and Fe3+ up to concentrations of 100 mg/L do not interfere with the adsorption process. Anions like sulphate, acetate and phosphate up to concentrations of 200 mg/L do not interfere. Chloride interferes in the adsorption process when Hg(II) concentration is above 9.7 mg/L. The adsorption equilibrium was established within two hours. Studies indicate that adsorption occurs on the surface sites of the adsorbent.

scholarly journals Impact of Iron on the Fe–Co–Ni Ternary Nanocomposites Structural and Magnetic Features Obtained via Chemical Precipitation Followed by Reduction Process for Various Magnetically Coupled Devices Applications

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 341
Author(s):  
Tien Hiep Nguyen ◽  
Gopalu Karunakaran ◽  
Yu.V. Konyukhov ◽  
Nguyen Van Minh ◽  
D.Yu. Karpenkov ◽  
...  
Keyword(s):  
Particle Size ◽  
Magnetic Properties ◽  
Reduction Process ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Magnetic Characteristics ◽  
Reduction Temperature ◽  
Fe Content ◽  
Magnetic Features ◽  
Co Precipitation

This paper presents the synthesis of Fe–Co–Ni nanocomposites by chemical precipitation, followed by a reduction process. It was found that the influence of the chemical composition and reduction temperature greatly alters the phase formation, its structures, particle size distribution, and magnetic properties of Fe–Co–Ni nanocomposites. The initial hydroxides of Fe–Co–Ni combinations were prepared by the co-precipitation method from nitrate precursors and precipitated using alkali. The reduction process was carried out by hydrogen in the temperature range of 300–500 °C under isothermal conditions. The nanocomposites had metallic and intermetallic phases with different lattice parameter values due to the increase in Fe content. In this paper, we showed that the values of the magnetic parameters of nanocomposites can be controlled in the ranges of MS = 7.6–192.5 Am2/kg, Mr = 0.4–39.7 Am2/kg, Mr/Ms = 0.02–0.32, and HcM = 4.72–60.68 kA/m by regulating the composition and reduction temperature of the Fe–Co–Ni composites. Due to the reduction process, drastic variations in the magnetic features result from the intermetallic and metallic face formation. The variation in magnetic characteristics is guided by the reduction degree, particle size growth, and crystallinity enhancement. Moreover, the reduction of the surface spins fraction of the nanocomposites under their growth induced an increase in the saturation magnetization. This is the first report where the influence of Fe content on the Fe–Co–Ni ternary system phase content and magnetic properties was evaluated. The Fe–Co–Ni ternary nanocomposites obtained by co-precipitation, followed by the hydrogen reduction led to the formation of better magnetic materials for various magnetically coupled device applications.

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