scholarly journals Preparation and Characterization of Nanocrystalline Cellulose from Cassava Stem Wastes by Electromagnetic Induction

2021 ◽  
Vol 16 (2) ◽  
pp. 109-117
Author(s):  
Lia Lismeri ◽  
Hertantri Yulia Rahmi ◽  
Nada Afifah Gomiyati ◽  
Yuli Darni ◽  
Panca Nugrahini Febriningrum ◽  
...  
Keyword(s):  
Acid Hydrolysis ◽  
Electromagnetic Induction ◽  
Average Particle Size ◽  
Nanocrystalline Cellulose ◽  
Raw Material ◽  
Induction Treatment ◽  
Average Particle ◽  
Cellulose Content ◽  
Naoh Solution ◽  
Cassava Stem

Cassava stems were one of the largest agricultural by products in Indonesia, especially in Lampung Province. It is known that cassava stems have a fairly high lignocellulose content, especially cellulose which reaches 39.29%. The high cellulose content in cassava stems has great potential to be used as raw material for Nanocrystalline Cellulose (NCC). The preparation of nanocrystalline cellulose consists of four main stages, namely: pre-hydrolysis, delignification, bleaching, and acid hydrolysis. The pre-hydrolysis stage was carried out by boiling a solution of CH3COOH and cassava stem powder for 60 minutes at a temperature of 105oC. Cassava stem powder was then delignified using a 25% NaOH solution heated to a temperature of 105oC for 1 hour. The bleaching stage used a 3.5% NaOCl solution at a temperature of 50oC for 60 minutes and was carried out twice. The last step is acid hydrolysis using 2.5N HCl solution for 15 minutes at a temperature of 105oC, then the electromagnetic induction treatment is varied with temperature variations of 30oC, 50oC, and 70oC for 60 minutes. The prepared nanocrystalline cellulose were tested for lignocellulose, XRD and PSA. From the test results, the best variation of nanocrystal cellulose preparation was acid hydrolysis treatment with 70oC electromagnetic induction for 60 minutes, namely an increase in the percentage of cellulose 62.93%, crystallinity 90.68%, and an average particle size of 18.04µm with some particles measuring nanometers. From the results of the research, it was concluded that electromagnetic induction increased crystallinity and decreased the size of nanocrystalline cellulose.

The Method of Obtaining Amorphous Nanosized Silicon Dioxide from Rice Production Waste

2019 ◽  
Vol 23 (4) ◽  
pp. 30-35
Author(s):  
Ngo Hong Nghia ◽  
L.A. Zenitova ◽  
Le Quang Dien ◽  
Dao Ngoc Truyen
Keyword(s):  
Silicon Dioxide ◽  
Rice Husk ◽  
Black Liquor ◽  
Average Particle Size ◽  
Amorphous Structure ◽  
Rice Production ◽  
Raw Material ◽  
Production Waste ◽  
Average Particle ◽  
Naoh Solution

The method of using rice husk, which is a rice production waste, as a raw material for the production of silicon dioxide as an alternative to synthetic silicon dioxide – aerosil is considered. A low-energy process for extracting silicon dioxide and cellulose from the husk by alkaline digestion in an NaOH solution was proposed, followed by treating the black liquor with an acid solution and calcining the precipitate at 575 °C during 5 hours. The yield of inorganic products from rice husk is determined based on the ash content of the pulp. It was shown that the product obtained mainly consists of silicon dioxide (SiO2) of amorphous structure, has an average particle size of less than 100 nm, which makes it possible to characterize it as nanosilica. At the same time, silicon dioxide consists of 51.7 % silicon and 48.3% oxygen against theoretical amounts of 30.4 % silicon and 69.6 % oxygen, respectively. The output of silicon dioxide is 8.8 % by weight of rice husk. At the same time, the process allows to obtain another valuable nanocellulose product.

Fe3O4 Magnetic Preparation by Bauxite Ore Washing Fine Mud

2014 ◽  
Vol 1010-1012 ◽  
pp. 961-965
Author(s):  
Jian Qiang Xiao ◽  
Guo Wei He ◽  
Yan Jin Hu
Keyword(s):  
Particle Size ◽  
Aging Time ◽  
Average Particle Size ◽  
Xrd Analysis ◽  
Test Methods ◽  
Raw Material ◽  
Molar Ratio ◽  
Average Particle ◽  
Experimental Conditions ◽  
Particle Size Analyzer

Bauxite waste sludge as a raw material, the use of reverse chemical coprecipitation synthesize Fe3O4. Researching temperature, precipitation concentration, aging time and Fe2+/Fe3+ molar ratio effect on the particle size, morphology. Optimal experimental conditions: temperature 70 °C, the precipitant NaOH mass ratio of 10%, aging time 3h, Fe2+/Fe3+ molar ratio of 2:3. Test methods using a laser particle size analyzer, XRD analysis of the products were characterized, the product is Fe3O4, the average particle size of 0.11mm.

scholarly journals Synthesis of Nanocrystalline Cellulose Stabilized Copper Nanoparticles

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Aminu Musa ◽  
Mansor B. Ahmad ◽  
Mohd Zobir Hussein ◽  
Saiman Mohd Izham ◽  
Kamyar Shameli ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Copper Nanoparticles ◽  
Metal Ion ◽  
Copper Ions ◽  
Chemical Reduction ◽  
Average Particle Size ◽  
Nanocrystalline Cellulose ◽  
Average Particle ◽  
Face Centered Cubic ◽  
X Ray

A chemical reduction method was employed for the synthesis of copper nanoparticles stabilized by nanocrystalline cellulose (NCC) using different concentrations of copper salt in aqueous solution under atmospheric air. CuSO4·5H2O salt and hydrazine were used as metal ion precursor and reducing agent, respectively. Ascorbic acid and aqueous NaOH were also used as an antioxidant and a pH moderator, respectively. The number of CuNPs increased with increasing concentration of the precursor salt. The formation of copper nanoparticles stabilized by NCC (CuNPs@NCC) was investigated by UV-visible spectroscopy (UV-vis), where the surface absorption maximum was observed at 590 nm. X-ray diffraction (XRD) analysis showed that the CuNPs@NCC are of a face-centered cubic structure. Moreover, the morphology of the CuNPs@NCC was investigated using transmission electron microscope (TEM) and field emission scanning electron microscope (FESEM), which showed well-dispersed CuNPs with an average particle size less than 4 nm and the shape of CuNPs was found to be spherical. Energy dispersive X-ray spectroscope (EDS) also confirmed the presence of CuNPs on the NCC. The results demonstrate that the stability of CuNPs decreases with an increasing concentration of the copper ions.

Innovative Preparation Calcium Hydroxyapatite from Duck Eggshell via Pyrolysis

2016 ◽  
Vol 851 ◽  
pp. 8-13
Author(s):  
Nuchnapa Tangboriboon ◽  
Jularpar Suttiprapar
Keyword(s):  
Calcium Carbonate ◽  
Calcium Phosphate ◽  
High Purity ◽  
Average Particle Size ◽  
Calcium Hydroxyapatite ◽  
Environmental Conservation ◽  
Raw Material ◽  
Carbonate Content ◽  
Average Particle ◽  
Ceramic Yield

Calcium hydroxyapatite made from duck eggshell react to phosphoric acid with the Ca/P mole ratio 1.67 and calcined at 800º, 900º, and 1000°C for each temperature 2 hr. Duck eggshell is a source of calcium carbonate having high purity content more than 98.101 %w/w and small amount of other metal oxides. Duck eggshell is a bio-material similar to other calcium sources i.e. coral, animal bone, and seashell. There are many advantages of using duck eggshell as a raw material such as abundant, low price, high purity of calcium carbonate content, easy to calcium phosphate formation, biocompatibility, bioactive, non-toxic for human, and the high percentage of ceramic yield 69.73%w/w. In addition, one of the most important advantages is to reduce the amount of duck eggshell waste from household and food industries as environmental conservation. The optimum condition to obtain high purity hydroxyapatite is sintering calcium phosphate at 1000°C for 2 hr. The average particle size, specific surface are, pore diameter, and true density of sample sintered at 1000°C for 2 hr are 39.92 µm, 2.12 m2/g, 98.96 Å, 3.02 g/cm3, respectively, in soft fine white powder. Furthermore, the results obtained by XRF, SEM, and XRD confirmed of sample fired at 1000°C for 2 hr to be calcium hydroxyapatite (HA, Ca10(PO4)6(OH)2) of Ca/P mole ratio 1.67 and small amount of calcium phosphate (β-TCP, Ca3PO4) of Ca/P mole ratio 1.5. Therefore, the duck eggshell is a potentially bio-ceramic material to prepare calcium hydroxyapatite applied for biomedical, bio-dental, and many industries i.e. pharmaceutical, toothpaste, cosmetic, and nutrient food etc.

Preparation and Photocatalytic Properties of Fe-Doped TiO2 Nanocrystalline Composite Particles

2010 ◽  
Vol 105-106 ◽  
pp. 815-818
Author(s):  
Hai Da Liao ◽  
Jin Lie Ma ◽  
Jian Dai
Keyword(s):  
Suspension Polymerization ◽  
Sol Gel ◽  
Average Particle Size ◽  
Raw Material ◽  
Composite Particles ◽  
Average Particle ◽  
Doped Tio2 ◽  
Catalytic Activities ◽  
Metatitanic Acid ◽  
Nanocrystalline Composite

Metatitanic acid was adopted as the raw material to prepare Fe-doped TiO2 nanocrystalline composite particles using suspension polymerization and sol-gel method, which were then characterized with XRD, TEM, TG-DTA and IR, etc.. The results showed the samples were nanocrystal accumulated porous particles, with average particle size of 29nm. Through doping of Fe3+ ion, the photo catalytic activities of particles under Xe lamp were investigated by photodegrading the methyl orange. It was found that, the TiO2 nanocrystal doped with 0.5% Fe3+ ion (accounted as mass fraction) had the highest catalytic activity. The Fe-doped TiO2 nanocrystalline composite particles prepared in this study has high activity, is easy for separation, recovery and reuse.

Finely milled kenaf core as a natural plywood binder

Holzforschung ◽  
2007 ◽  
Vol 61 (4) ◽  
pp. 439-444 ◽  
Author(s):  
Nobuhisa Okuda ◽  
Masatoshi Sato
Keyword(s):  
Close Contact ◽  
Average Particle Size ◽  
Raw Material ◽  
Average Particle ◽  
Wood Powder ◽  
Tensile Shear ◽  
Pressing Temperature ◽  
Board Density ◽  
Kenaf Core ◽  
Core Powder

Abstract Application of kenaf core powder as a natural plywood binder has been studied. In the first instance, binderless boards made of kenaf core powder and overlaid sugi (Cryptomeria japonica D. Don) veneers resulted in immediate veneer delamination. However, binderless boards were successfully manufactured from sugi wood powder and had an internal bonding strength of 1.69 MPa. The board properties improved with increasing fineness of the raw material, increasing pressing temperature, and increasing board density. Essential prerequisites for binderless adhesion are: (1) particles should be situated close to each other to allow the formation of chemical bonds; and (2) a high pressing temperature is necessary to melt the solid-solid interfaces between the particles and to supply the activation energy for chemical reactions. For successful adaptation of these requirements, the kenaf core powder should have an average particle size of approximately 10 μm, which then mediates close contact between veneers. Plywood bonded with kenaf core powder had an average tensile shear strength of 0.96 MPa with a wood failure rate of 82.1%. Accordingly, vibratory ball milling activates kenaf core and the powder is suitable as a natural plywood binder.

scholarly journals Preparation and Characterization of Ultra-Fine Oil Palm Ash Powder by Ultrasonication and Alkaline Treatment for Its Evaluation as Reinforcing Filler in Natural Rubber

Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 100
Author(s):  
Methakarn Jarnthong ◽  
Chutarat Malawet ◽  
Lusheng Liao ◽  
Puwang Li ◽  
Zheng Peng ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Natural Rubber ◽  
Oil Palm ◽  
Average Particle Size ◽  
Alkaline Treatment ◽  
Bet Surface Area ◽  
Average Particle ◽  
Naoh Solution ◽  
Oil Palm Ash

Ultra-fine oil palm ash (OPA) particles were successfully prepared using ultrasonication along with optimal chemical deagglomeration. The influence of chemical treatment by sodium hydroxide (NaOH) solution on the OPA particles was found to be an important factor in enhancing deagglomeration efficiency. The average particle size of the original OPA (41.651 μm) decreased remarkably more than 130 times (0.318 μm) with an obvious increase of Brunauer–Emmet–Teller (BET) surface area after treating the OPA with 3M NaOH, followed by ultrasonication for 30 min. The changes in particle size and surface morphology were investigated using transmission electron microscopy and scanning electron microscopy. Moreover, the chemical functional groups of the untreated and treated OPA showed different patterns of infrared spectra by the presence of sodium carbonate species owing to the effect of NaOH treatment. The incorporation of both untreated and treated OPA in natural rubber by increasing their loading can improve cure characteristics (i.e., reducing optimum cure time and increasing torques) and cure kinetic parameters (i.e., increasing the rate of cure and reducing activation energy). Nevertheless, the strength, degree of reinforcement, and thermal stability of treated OPA as well as wettability between treated OPA particles and NR were greater than that resulting from the untreated OPA.

Synthesis of Type-A Zeolite in Hydrothermal Condition with Stellerite

2011 ◽  
Vol 194-196 ◽  
pp. 492-496 ◽  
Author(s):  
Nan Chun Chen ◽  
Quan Tang ◽  
Ai Ping Deng ◽  
Wei Wang ◽  
Xiao Hu Zhang
Keyword(s):  
Crystallization Temperature ◽  
Average Particle Size ◽  
Functional Materials ◽  
Hydrothermal Condition ◽  
Type A ◽  
Raw Material ◽  
Crystallization Time ◽  
Average Particle ◽  
Type Zeolite ◽  
Chemical Materials

Type-A zeolite was synthesized in hydrothermal condition with stellerite obtained from Guangxi. The influences of raw material modification, crystallization temperature, crystallization time and particles’size of stellerites were discussed on preparing zeolite molecular sieve. It is shown that A-type zeolite was synthesized in crystallization time of 6 hours, crystallization temperature of 90-100 °C according to certain proportion with stellerite modified by hydrochloric acid of 15%. The crystallinity of A-type zeolite is 98%, whiteness 95%, average particle size 3.72 µm and more than 90% particles’size are less than 10μm. These meet the zeolite standards of Q / Chalco A021-2004. Type-A zeolite is widely used in detergent industry, petrochemical industry, chemical industry, environmental protection and development of new functional materials fields as it has many excellent performance, such as good ion exchange, adsorption and catalysis, due to its unique crystal structure[1-4]. Because the synthesis of type-A zeolite based on chemical materials costs too much and is also restricted by chemical materials, which can not meet the needs of zeolite application. Therefore, researchers have become focus on preparing type-A zeolite with cheap mineral- materials[5-8]. In this research, we prepared type-A zeolite through Hydrothermal method with stellerites obtained from Guangxi.

Preparation and Characterization of Macromeritic Tungsten Powder Reduced by Ammonium Paratungstate at Medium Temperature

2012 ◽  
Vol 468-471 ◽  
pp. 2584-2587
Author(s):  
Rui Xin Wang ◽  
Zhi Meng Guo ◽  
Jun Jie Hao ◽  
Ji Luo ◽  
Yan Jun Xin
Keyword(s):  
Particle Size ◽  
Hydrogen Reduction ◽  
Tungsten Powder ◽  
Average Particle Size ◽  
Raw Material ◽  
Metal Salts ◽  
Average Particle ◽  
Medium Temperature ◽  
Ammonium Paratungstate ◽  
Ammonium Tungstate

The macromeritic tungsten powder was prepared by wet hydrogen reduction at medium temperature; the coarse powder of Ammonium paratungstate powder (APT) was used as raw material. It is obtained by evaporating and crystallizating adding alkalia metal salts in the solution of ammonium tungstate. The microstructure, phase composition and particle size of the macromeritic tungsten powder were investigated by SEM, XRD and test analysis sieves. The effects of kinds, contents of alkali metal salts and the temperature in the reduction were studied. The results revealed that ideal tungsten powder, with the good fluditity, spherical, integrate and well-distributed, could be obtained. The raw material is the solution of ammonium tungstate adding NaCl, Li2CO3 and KCl , the concentration of them are all 3g/L, and it is under the condition of 1000°C,180min in wet hydrogen atmosphere. The average particle size is 67μm, the maximum is 150μm, the biggest loose density is 13.41g/cm3, and the best powder flowability is 9s/50g.

THE MANUFACTURING OF NIOBIUM POWDER BY HUNTER PROCESS

2010 ◽  
Vol 17 (02) ◽  
pp. 223-228
Author(s):  
JAE-SIK YOON
Keyword(s):  
Particle Size ◽  
Reaction Temperature ◽  
Average Particle Size ◽  
Reduction Process ◽  
Reducing Agent ◽  
Raw Material ◽  
Average Particle ◽  
Metallothermic Reduction ◽  
Niobium Powder ◽  
Yield Rate

Niobium powder was fabricated by metallothermic reduction process using K2NbF7 as the raw material, KCl and KF as the diluents and Na as the reducing agent. The apparatus for the experiment was designed and built specifically for the present study. Varying properties of niobium powder depending on reaction temperature and excess of reducing agent were analyzed. The niobium particle size increased significantly as the reduction temperature increased from 993 to 1093 K. The particle size was fairly uniform at a given reaction temperature, varying from 0.2 μ m to 50 nm depending on the reaction temperature. The yield of niobium powder increased from 58 to 83% with an increase in reaction temperature. The average particle size of niobium powder was improved from 70 nm to 0.2 μ m with the increase in the amount of Na excess. In addition, the yield rate of Nb powder was 82% in the 5% excess sodium.

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