Preparing Nanosilica Particles from Rice Husk Using Precipitation Method

Effect of nanosilica size on physic-mechanical properties, thermal stability and weathering durability of coating based on acrylic emulsion. Nanocomposite coating formulas were filled by 2 wt.% nanosilica particles which were used in this study, namely: nanosilica from Sigma (15-20nm), nansilica from rice husk (~70-200 nm) and nanosilica from Arosil – Belgium (7-12 nm). Obtained results showed that viscosity flow of coating formula containing nanosilica from Arosil saw the highest flow-time while coating formulas filled other nanosilica and unfilled nanosilica experienced similar flow-time. In presence of nanosilica, coating properties were improved in comparison with neat coating. However, coating filled by nanosilica from rice husk indicated the best properties in studied coating formula. It may explained that size of nanosilica from rice husk was the largest in studied nanosilica particles and thus easily dispersing into coating formula.

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Leaching characteristics and kinetics of the metal impurities present in rice husk during pretreatment for the production of nanosilica particles

Korean Journal of Chemical Engineering ◽

10.1007/s11814-018-0103-z ◽

2018 ◽

Vol 35 (9) ◽

pp. 1911-1918 ◽

Cited By ~ 3

Author(s):

Pei Chen ◽

Haipei Bie ◽

Rushan Bie

Keyword(s):

Rice Husk ◽

Metal Impurities ◽

Leaching Characteristics ◽

Nanosilica Particles ◽

Kinetics Of

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Modified Activated Graphene-Based Carbon Electrodes from Rice Husk for Supercapacitor Applications

Energies ◽

10.3390/en13184943 ◽

2020 ◽

Vol 13 (18) ◽

pp. 4943

Author(s):

Mukhtar Yeleuov ◽

Christopher Seidl ◽

Tolganay Temirgaliyeva ◽

Azamat Taurbekov ◽

Nicholay Prikhodko ◽

...

Keyword(s):

Specific Capacitance ◽

Rice Husk ◽

Low Cost ◽

Agricultural Waste ◽

Chemical Precipitation ◽

High Specific Surface Area ◽

Precipitation Method ◽

Renewable Biomass ◽

Transmission Electron ◽

Chemical Procedure

The renewable biomass material obtained from rice husk, a low-cost agricultural waste, was used as a precursor to synthesize a highly porous graphene-based carbon as electrode material for supercapacitors. Activated graphene-based carbon (AGC) was obtained by a two-step chemical procedure and exhibited a very high specific surface area (SSA) of 3292 m2 g−1. The surface morphology of the synthesized materials was studied using scanning and transmission electron microscopy (SEM, TEM). Furthermore, the AGC was modified with nickel hydroxide Ni(OH)2 through a simple chemical precipitation method. It was found that the most significant increase in capacitance could be reached with Ni(OH)2 loadings of around 9 wt.%. The measured specific capacitance of the pure AGC supercapacitor electrodes was 236 F g−1, whereas electrodes from the material modified with 9 wt.% Ni(OH)2 showed a specific capacitance of up to 300 F g−1 at a current density of 50 mA g−1. The increase in specific capacitance achieved due to chemical modification was, therefore 27%.

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Recovery of silica and carbon black from rice husk ash disposed from a biomass power plant by precipitation method

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/373/1/012026 ◽

2019 ◽

Vol 373 ◽

pp. 012026

Author(s):

B Thongma ◽

S Chiarakorn

Keyword(s):

Power Plant ◽

Carbon Black ◽

Rice Husk ◽

Rice Husk Ash ◽

Precipitation Method ◽

Biomass Power Plant

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Preparation of Nanosilica Powder Using Rice Husk via Precipitation Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1010.501 ◽

2020 ◽

Vol 1010 ◽

pp. 501-507

Author(s):

Farah Diana Mohd Daud ◽

Nur Aishah M. Azmy ◽

Mudrikah Sofia Mahmud ◽

Norshahida Sariffudin ◽

Hafizah Hanim Mohd Zaki

Keyword(s):

Particle Size ◽

Electron Microscope ◽

Thermal Treatment ◽

Scanning Electron Microscope ◽

Rice Husk ◽

Acid Leaching ◽

Precipitation Method ◽

X Ray ◽

Mean Particle Size ◽

Scanning Electron

Silica in nanoscale has various superior properties which leads to a wide range of applications. Most researches used and metal alkoxides as the sources but very few researches attempted at preparing nanosilica powder from the agricultural waste which environmental friendly and inexpensive. This research is presented as the studies of optimization of parameters involved during preparation, aimed to improve the purity of silica produced. In this work, rice husk ash (RHA) precursor was subjected to precipitation method in order to produce nanosilica powder. Acid leaching and thermal treatment were done as a pre-synthesis process. The process parameters that have been studied were the refluxed NaOH concentration, heating time, and temperature, in which the properties were then evaluated during characterization process. The results from X-Ray Flourescence (XRF) confirmed that it is possible to extract 100% purity of silica from RHA treated by the combination of thermal treatment, acid leaching, refluxed with 2.5 M of NaOH and heated at 50°C for 48 hours. X-Ray Diffraction (XRD) illustrated that the produced silica is in amorphous state. Meanwhile, the mean particle size of the spherical shape of silica obtained ranging from 44.7 nm to 1.23 μm. Therefore, the best mean particle size obtained was by using the sample refluxed with 2.5 M NaOH and heated at 50°C for 48 hours, which were confirmed by Scanning Electron Microscope (SEM) and Field Emission Scanning Electron Microscope (FESEM). These findings on the optimum parameters indicate the successful production of highest purity of nanosilica powder with nanoscaled particle size.

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Low-Cost and Fast Production of Nano-Silica from Rice Husk Ash

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.979.216 ◽

2014 ◽

Vol 979 ◽

pp. 216-219 ◽

Cited By ~ 6

Author(s):

Weerachon Phoohinkong ◽

Udomsak Kitthawee

Keyword(s):

Electron Microscopy ◽

Sodium Chloride ◽

Sodium Silicate ◽

Rice Husk ◽

Power Plants ◽

Rice Husk Ash ◽

Synthesis Method ◽

Precipitation Method ◽

High Quality ◽

Flow Synthesis

Silica with nanostructure are the high quality silica that are used in many industry areas. The applications of silica nanostructure frequently depend on physical properties such as morphology and size of structure. Rice husk ash is the waste from biomass power plants and is a high quality, raw material as a silica source. The conventional methods for synthesis of nanosilica from rice husk ash are energy consumption or time consumption. The objective of this work was to investigate the synthesized of nanosilica from rice husk ash via sodium silicate solution. nanosilica particles were obtained via alkaline extraction and a fast acid precipitation method at room temperature by adding inorganic salts and without surfactant or template. The flow synthesis was investigated at ambient temperature, varying the concentration of hydrochloric acid, sodium chloride, and flow-rate while fixing the concentration of sodium silicate. The samples were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The results revealed that the sodium chloride is significantly inorganic salt for generated nanosilica, with uniform spherical morphology (80-150 nm), without curing or aging time. In the flow synthesis method, the silica nanoparticles, of diameter around 10 nm and aggregate particles of around 50 to 200 nm, were obtained. This method may be applicable to control different grade of silica and can easily scaling up of silica production for different industries.

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The Fractionation Properties of Human Factor VIII (Antihaemophilic Factor)

Thrombosis and Haemostasis ◽

10.1055/s-0038-1654503 ◽

1960 ◽

Vol 04 (02) ◽

pp. 253-260 ◽

Cited By ~ 1

Author(s):

Franco Gobbi

Keyword(s):

Factor Viii ◽

Human Factor ◽

Maximum Yield ◽

Factor Vii ◽

Precipitation Method ◽

Salting Out ◽

Human Factor Viii ◽

Plasma Factor ◽

Two Factors ◽

Thromboplastic Activity

SummaryThe fractionation properties of human Factor VIII (antihaemophilic factor, AHF, antihaemophilic globulin) have been studied using a plasma of congenital afibrinogenaemia as a starting material.From a fibrinogen-free plasma, Factor VIII does not precipitate with ethanol at a final concentration of 8%; on the contrary the maximum yield is reached at an ethanol concentration of 25%.With a precipitation method carried out by a one to ten dilution of plasma with distilled water and acidification by N/10 hydrochloric acid to a pFI 5.2, Factor VIII does not precipitate with the euglobulin fraction; when normal plasma is used, such a precipitation is almost complete.With the salting-out fractionation method by ammonium sulphate, Factor VIII precipitates at a concentration between 25 and 33% of saturation either from fibrinogen-free and from normal human plasma.A non-specific thromboplastic activity appears in the fractions prepared by every method. This activity, which is probably due to the activation of seric accelerators, is easily removed by Al(OH)s adsorption. Thus, in order to insure the specificity of Factor VIII assays, the preliminary adsorption of the fractions is indispensable before testing their antihaemophilic activity.Fibrinogen and Factor VIII have different and definite precipitation patterns. When these two factors are associated the fractionation properties of AHF appear quite modified, showing a close similarity to those of fibrinogen. This fact can explain the technical difficulties encountered in the attempt to purify the antihaemophilic factor, and the lack of reproducible procedures for removing fibrinogen without affecting Factor VII.

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Mechanoactivation Of Rice Husk Ash In Laboratory Conditions

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2019.11.20-26 ◽

2019 ◽

pp. 20-26

Keyword(s):

Mechanical Activation ◽

Rice Husk ◽

Amorphous Silica ◽

Silicon Oxide ◽

Rice Husk Ash ◽

Pozzolanic Activity ◽

Maximum Solubility ◽

Laboratory Conditions ◽

Before And After ◽

Mineral Additive

In many rice producing countries of the world, including in Vietnam, various research aimed at using rice husk ash (RHA) as a finely dispersed active mineral additive in cements, concrete and mortars are being conducted. The effect of the duration of the mechanoactivation of the RHA, produced under laboratory conditions in Vietnam, on its pozzolanic activity were investigated in this study. The composition of ash was investigated by laser granulometry and the values of indicators characterizing the dispersion of its particles before and after mechanical activation were established. The content of soluble amorphous silicon oxide in rice husk ash samples was determined by photocolorimetric analysis. The pizzolanic activity of the RHA, fly ash and the silica fume was also compared according to the method of absorption of the solution of the active mineral additive. It is established that the duration of the mechanical activation of rice husk ash by grinding in a vibratory mill is optimal for increasing its pozzolanic activity, since it simultaneously results in the production of the most dispersed ash particles with the highest specific surface area and maximum solubility of the amorphous silica contained in it. Longer grinding does not lead to further reduction in the size of ash particles, which can be explained by their aggregation, and also reduces the solubility of amorphous silica in an aqueous alkaline medium.

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