Preparation of Nano-Iron Oxide Red from Bio-Oxidation Wastewater

2011 ◽  
Vol 233-235 ◽  
pp. 794-797
Author(s):  
Qian Li ◽  
Kai Yu ◽  
Ping Mu ◽  
Yan Wen Tian ◽  
Jian Zhong Li
Keyword(s):  
Iron Oxide ◽  
Ph Value ◽  
Chemical Deposition ◽  
Average Diameter ◽  
Process Conditions ◽  
Light Region ◽  
Valuable Element ◽  
The Difference ◽  
Good Transparency ◽  
Partical Size

According to the difference of chemical deposition behavior of arsenic and iron ion in the different pH value solution, valuable element Fe was first recovered by the selective deposition from bio-oxidation wastewater and then it was used to prepare nano-iron oxide red pigment powders. The effect of purifying conditions, calcinations temperature and calcinations time on the product color, the average partical size had been investigated. The crystal structure, particle-size and properties of the nanoparticles were characterized by means of XRD, TEM. The optimal process conditions of the preparation of iron oxide red were: calcinations temperature was 900°C, calcinations time was 120min. Under these conditions, the color of production was bright red. The particles were fully developed, and the average diameter of nanometer particle was about 70.8nm. In the visible light region of 380 to 780nm, the particle possessed good transparency, achieving the standard of GB1863 – 89.

Study on the Enzyme Desizing Process for Cotton Fabric Using Ultrasonication

2011 ◽  
Vol 331 ◽  
pp. 261-264 ◽  
Author(s):  
Qi Ming Zhao ◽  
Shan Yan Zhang
Keyword(s):  
Cotton Fabric ◽  
Ph Value ◽  
Orthogonal Experiment ◽  
Research Result ◽  
Strength Loss ◽  
Cotton Fabrics ◽  
Optimum Process ◽  
Process Conditions ◽  
Fabric Strength ◽  
Enzyme Dosage

The auxiliary devices of ultrasonic treatment was designed and manufactured. The cotton fabric was desized using 2000L desizing enzyme with the conventional enzyme desizing process and ultrasonic enzyme desizing process respectively. Through the orthogonal experiment, the optimum process conditions of conventional enzyme desizing process and ultrasonic enzyme desizing process were determined. For the conventional enzyme desizing process, the optimized desizing conditions of cotton fabrics were: desizing enzyme dosage was 1.5g/l, temperature was 80°C, PH value was 6, and time was 60mins. The optimum process conditions of ultrasonic enzyme desizing process were: desizing enzyme dosage was 1.5g/l, temperature was 50°C, PH value was 6 and time was 45minutes. The research result indicates that, under the same desizing condition, ultrasonication can improve the desizing percentage and whiteness of cotton fabric, but the fabric strength loss increases slightly. And for the same required desizing percentage, the ultrasonic enzyme desizing process saved time and reduced the temperature of experiments compared with traditional enzyme desizing process

Synthesis of Polyurethane Dendrimers and Transfer Properties of Dye

2013 ◽  
Vol 457-458 ◽  
pp. 65-71
Author(s):  
Jing Ru Jia
Keyword(s):  
Methyl Orange ◽  
Phase Transfer ◽  
Raw Materials ◽  
Toluene Diisocyanate ◽  
Polymerization Process ◽  
Process Conditions ◽  
Addition Polymerization ◽  
Different Temperatures ◽  
The Difference ◽  
Transfer Properties

The polyfunctional organic compounds 2- hydroxymethyl -1,4- butanediol (trihydric alcohol) and toluene diisocyanate -2, 4- diisocyanate (TDI) were taken as the raw materials in this study. A polyurethane dendrimer was synthesized by utilizing the difference in the reaction activity of two isocyanate groups of TDI at different temperatures. The polymerization process conditions were studied. The addition polymerization of para-position NCO groups occurred at 50 °C, and that of ortho NCO groups occurred at 90 °C. According to the structure of the dendrimer synthesized, methyl orange was used as the guest molecule. Consequently, the aqueous methyl orange showed a phase transfer. With the increase of dendrimer concentration, the transfer rate of methyl orange increased.

Effect of pH Value on the Synthesis of NiO Nanoparticles and Microstructure of NiO Based Composite Anode

2021 ◽  
Vol 317 ◽  
pp. 447-453
Author(s):  
Noor Hidayah Aniza Zakaria ◽  
Nafisah Osman
Keyword(s):  
Ph Value ◽  
Sol Gel ◽  
Secondary Phase ◽  
Average Diameter ◽  
Morphological Observation ◽  
Nio Nanoparticles ◽  
Composite Anode ◽  
Ph Values ◽  
Particle Size Analyzer ◽  
Nio Nps

NiO nanoparticle was synthesized by a sol-gel method with three different pH values namely pH=1, 7 and 11, and then calcined at temperature of 450 ᵒC. The influence of different pH values on the physical properties of NiO nanoparticles were investigated by a particle size analyzer (PSA), field emission scanning electron microscope (FESEM) and X-ray diffractometer (XRD). Structural analysis confirmed that a cubic structure of NiO nanoparticle was obtained without any secondary phase for NiO powders prepared with pH=1, while the peak of secondary phase (Ni) appeared for NiO powders prepared with pH= 7 and 11. Morphological observation showed that the NiO nanoparticles prepared with pH=7 and 11 tend to form more agglomerates compared to one prepared with pH=1. The average diameter of NiO nanoparticles with pH 1, 7 and 11 were approximately in the range of 19-26 nm, 21-28 nm, and 24-30 nm, respectively. NiO powder that was synthesized with pH=1 was further used to prepare composite anode of NiO Nps-BaCe0.54Zr0.36Y0.1O2.95 (BCZY) powder. Unfortunately a composite of NiO Nps-BaCeO3-BaZrO3 was obtained instead of BCZY and governed by agglomerates with size in the range of 70-300 nm.

scholarly journals THE ACCUMULATION OF ELECTROLYTES

1932 ◽  
Vol 15 (6) ◽  
pp. 667-689 ◽  
Author(s):  
W. J. V. Osterhout ◽  
W. M. Stanley
Keyword(s):  
Steady State ◽  
Osmotic Pressure ◽  
Aqueous Phase ◽  
Thermodynamic Potential ◽  
Ph Value ◽  
Molecular Form ◽  
External Solution ◽  
Aqueous Layer ◽  
The Difference ◽  
Pass Through

Inasmuch as attempts to explain accumulation by the Donnan principle have failed in the case of Valonia, a hypothesis of the steady state has been formulated to explain what occurs. In order to see whether this hypothesis is in harmony with physico-chemical laws attempts have been made to imitate its chief features by means of a model. The model consists of a non-aqueous layer (representing the protoplasmic surface) placed between an alkaline aqueous phase (representing the external solution) and a more acid aqueous phase (representing the cell sap). The model reproduces most of the features of the hypothesis. Attention may be called to the following points. 1. The semipermeable surface is a continuous non-aqueous phase. 2. Potassium penetrates by combining with an acid HX in the non-aqueous layer to form KX which in turn reacts with an acid HA in the sap to form KA. Since KX is little dissociated in the non-aqueous layer potassium appears to pass through it chiefly in molecular form. 3. The internal composition depends on permeability, e.g., sodium penetrates less rapidly than potassium and in consequence potassium predominates over sodium in the "artificial sap." The order of penetration in the model is the same as in Valonia, i.e., K > Na > Ca > Mg, and Cl > SO4, but the quantitative resemblance is not close, e.g., the difference between potassium and sodium, and chloride and sulfate is much less in the model. 4. The formation of KA and NaA in the sap raises its osmotic pressure and water enters. 5. The concentration of potassium and sodium and the osmotic pressure become much greater inside than outside. For example, potassium may become 200 times as concentrated inside as outside. 6. No equilibrium occurs but a steady state is reached in which water and salt enter at the same rate so that the composition of the sap remains constant as its volume increases. 7. Since no equilibrium occurs there is a difference of thermodynamic potential between inside and outside. At the start the thermodynamic potential of KOH is much greater outside than inside. This difference gradually diminishes and in the steady state has about the same value as in Valonia. The difference in pH value between the internal and external solutions is also similar in both cases (about 2 pH units). 8. Accumulation does not depend on the presence of molecules or ions inside which are unable to pass out. One important feature of the hypothesis is not seen in the model: this is the exchange of HCO3 for Cl-. Experiments on this point are in progress.

scholarly journals Equilibrium modeling of mono and binary sorption of Cu(II) and Zn(II) onto chitosan gel beads

2016 ◽  
Vol 37 (4) ◽  
pp. 485-501 ◽  
Author(s):  
Józef Nastaj ◽  
Małgorzata Tuligłowicz ◽  
Konrad Witkiewicz
Keyword(s):  
Metal Ion ◽  
Ph Value ◽  
Experimental Studies ◽  
Process Conditions ◽  
Optimal Process ◽  
Sorption Data ◽  
Gel Beads ◽  
Two Component ◽  
Equilibrium Data ◽  
Chitosan Gel

Abstract The objective of the work are in-depth experimental studies of Cu(II) and Zn(II) ion removal on chitosan gel beads from both one- and two-component water solutions at the temperature of 303 K. The optimal process conditions such as: pH value, dose of sorbent and contact time were determined. Based on the optimal process conditions, equilibrium and kinetic studies were carried out. The maximum sorption capacities equaled: 191.25 mg/g and 142.88 mg/g for Cu(II) and Zn(II) ions respectively, when the sorbent dose was 10 g/L and the pH of a solution was 5.0 for both heavy metal ions. One-component sorption equilibrium data were successfully presented for six of the most useful three-parameter equilibrium models: Langmuir-Freundlich, Redlich-Peterson, Sips, Koble-Corrigan, Hill and Toth. Extended forms of Langmuir-Freundlich, Koble-Corrigan and Sips models were also well fitted to the two-component equilibrium data obtained for different ratios of concentrations of Cu(II) and Zn(II) ions (1:1, 1:2, 2:1). Experimental sorption data were described by two kinetic models of the pseudo-first and pseudo-second order. Furthermore, an attempt to explain the mechanisms of the divalent metal ion sorption process on chitosan gel beads was undertaken.

scholarly journals Study on Aqueous Enzymatic Extraction Process of Common Pistache Oil

2021 ◽  
Vol 251 ◽  
pp. 02058
Author(s):  
Feng Xuehua ◽  
Tao Ali ◽  
Song Zurong ◽  
Gong Panpan
Keyword(s):  
Ph Value ◽  
Orthogonal Experiment ◽  
Extraction Process ◽  
Optimal Time ◽  
Process Conditions ◽  
Optimal Process ◽  
Enzymatic Extraction ◽  
Hydrolysis Time ◽  
Aqueous Enzymatic Extraction ◽  
The Common

The aqueous enzymatic method was applied to extract the common pistache oil and the optimal extraction process conditions were identified. By observing the effect of enzymatic hydrolysis time, pH value, temperature on aqueous enzymatic extraction process and performing the orthogonal experiment based on the single factor test, the optimal process parameters were obtained, namely, the optimal time, temperature, and pH value were respectively 3 h, 50℃, and 7 with a final extraction rate of 25.38 %.

Modelling Flue Gas Desulfurization Using Pyrolusite Pulp in a Jet Bubbling Reactor

2009 ◽  
Vol 610-613 ◽  
pp. 85-96 ◽  
Author(s):  
Jing Dong Zhao ◽  
Shi Jun Su ◽  
Nan Shan Ai ◽  
Xiao Fan Zhu
Keyword(s):  
Flue Gas ◽  
Ph Value ◽  
Scale Up ◽  
Absorption Efficiency ◽  
Flue Gas Desulfurization ◽  
Process Conditions ◽  
Gas Temperature ◽  
Transfer Coefficients ◽  
Set Up ◽  
So2 Absorption

A mathematical model for flue gas desulfurization using pyrolusite pulp in jet bubbling reactor (JBR) was described. Firstly, based on the concept of two stages mass balance with chemical reaction, two models were set up, for jet bubbling zone and rising bubble zone, respectively, according to the construction of JBR. The models consist of two coupling differential equations and were solved simultaneously by integral and separation of the variables. Then the SO2 absorption efficiency expression was developed, considering the great discrepancy existing between the gas-side mass transfer coefficients of the jet bubbling zone and gas bubble rising zone. The final expression associates SO2 absorption efficiency with process conditions and JBR structure parameters, which can give some instruction and guidance for the study of reactor operation process. Predicted results from the theoretical model, including effect of pH value of the pulp, flue gas temperature and inlet SO2 concentration of flue gas on SO2 absorption efficiency, were found to be in good agreement with experimental data obtained in a jet bubbling reactor. The model provides a basis for the process scale up and operating guide.

Influence of Sargassum crassifolium Extract on the Absorption of Magnetic Iron Oxide Nanoparticle via Green Synthesis Route

2019 ◽  
Vol 803 ◽  
pp. 382-386 ◽  
Author(s):  
Marco Laurence M. Budlayan ◽  
Arnold C. Alguno ◽  
Rey Y. Capangpangan
Keyword(s):  
Iron Oxide ◽  
Green Synthesis ◽  
Average Diameter ◽  
Seaweed Extract ◽  
Iron Oxide Nanoparticle ◽  
Magnetic Iron Oxide Nanoparticles ◽  
Environmental Application ◽  
Magnetic Iron Oxide ◽  
Synthesis Route ◽  
20 Nm

This work reported the influence of seaweed (Sargassumcrassifolium) extract on the absorption of magnetic iron oxide nanoparticles (MIONPs) via green synthesis route. The seaweed extract acted as reducing and capping agent. Ultraviolet-visible (UV-Vis) spectra revealed the presence of sharp peaks at around 366 nm to 371 nm which corresponds to the absorption spectra of MIONPs. The absorption peaks corresponding to MIONPs was significantly affected by the varying amount of seaweed extract. On the other hand, Fourier Transform-Infrared (FTIR) spectra revealed the presence of the vibration mode around 532 cm-1 to 551 cm-1 which corresponds to Fe-O bands suggesting the successful formation of MIONPs. Thermogravimetric (TGA) spectra showed that the produced MIONPs stabilizes at 400 °C. The synthesized MIONPs are spherical in shape with an estimated average diameter of 20 nm as revealed by the Field Emission Scanning Electron Microscopy (FESEM). Finally, the produced MIONPs exhibit magnetic property via attraction with an external magnet. This straight forward green synthesis of MIONPs can be a good route for possible industrial and environmental application.

scholarly journals Silicon Nanowires: Growth Studies Using Pulsed PECVD

2007 ◽  
Vol 989 ◽  
Author(s):  
David Parlevliet ◽  
John C.L. Cornish
Keyword(s):  
Silicon Nanowires ◽  
Average Length ◽  
Gold Catalyst ◽  
Chemical Deposition ◽  
Catalyst Layer ◽  
Average Diameter ◽  
Scattered Electron ◽  
Aspect Ratios ◽  
Copper Indium ◽  
Gold Silver

AbstractSilicon nanowires with high aspect ratios have been grown at high density using a variation of Plasma Enhanced Chemical Deposition (PECVD) known as Pulsed PECVD (PPECVD). Growth rate and morphology were investigated for a range of catalysts: gold, silver, aluminum, copper, indium and tin. The thickness of the catalyst layer was 100nm. Deposition was carried out in a parallel plate PECVD chamber at substrate temperatures up to 350°C, from undiluted semiconductor grade Silane. A 1 kHz square wave was used to modulate the 13.56 MHz RF power. Samples were analyzed using either a Phillips XL20 SEM or a ZEISS 1555 VP FESEM. The average diameter for nanowires grown using a gold catalyst layer was 150nm and the average length was 4μm although some nanowires were observed with lengths up to 20μm. Back-scattered-electron images clearly show gold present at the tips of the silicon nanowires grown using gold as a catalyst, confirming their growth by the vapor liquid solid (VLS) mechanism. Sporadic growth of nanowires was detected when using copper as a catalyst. Although gold performed best as catalyst for nanowire growth it was, however, closely followed by tin. The other catalysts produced nanowires with properties between these extremes.

Sonochemical Synthesis of Silica Coated Super Paramagnetic Iron Oxide Nanoparticles

2013 ◽  
Vol 756 ◽  
pp. 74-79 ◽  
Author(s):  
Bashiru Kayode Sodipo ◽  
Azlan Abdul Aziz
Keyword(s):  
Iron Oxide ◽  
Silica Nanoparticles ◽  
Iron Oxide Nanoparticles ◽  
Ph Value ◽  
Superparamagnetic Iron Oxide ◽  
Silica Nanoparticle ◽  
Precipitation Method ◽  
Oxide Nanoparticles ◽  
Sonochemical Method ◽  
Co Precipitation

Superparamagnetic iron oxide nanoparticles (SPION) of sizes 5 to10 nm were synthesized by the co-precipitation method. They are coated with silica nanoparticles using sonication method. The SPION was produced under the optimum pH of 10, peptized in acidic medium and redispersed in water. The silica nanoparticles were produced through the Stöbermethod. Sonochemical coating of silica nanoparticle on the SPION was successfulat a pH value lower than 5. Otherwise, at higher pH value (but lower than point zero charge (PZC)), the SPION were found to be unstable. Fast hydrolysis of triethoxyvinylsilane(TEVS) shows that silica forms its own particles without coating onto the surfaces of the SPION. Under optimized experimental condition, sonochemical method of coating silica nanoparticles onto the SPION can be considered as an alternative for effective and prompt method that rely mainly on pH of the suspension.

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