scholarly journals Dimensional Stability of Treated Sengon Wood by Nano-Silica of Betung Bamboo Leaves

Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1581
Author(s):  
Istie Rahayu ◽  
Fitria Cita Dirna ◽  
Akhiruddin Maddu ◽  
Wayan Darmawan ◽  
Dodi Nandika ◽  
...  

Sengon (Falcataria moluccana Miq.) is one of the fastest growing wood that is broadly planted in Indonesia. Sengon wood has inferior wood properties, such as a low density and dimensional stability. Therefore, sengon wood requires a method to improve its wood quality through wood modification. One type of wood modification is wood impregnation. On the other hand, Betung Bamboo leaves are considered as waste. Betung Bamboo leaves contain silica. Based on several researches, nano-SiO2 could improve fast-growing wood qualities. According to its perfect solubility in water, monoethylene glycol (MEG) is used in the study. The objectives are to evaluate the impregnation treatment (MEG and nano-silica originated from betung bamboo leaves) in regard to the dimensional stability and density of 5-year-old sengon wood and to characterize the treated sengon wood. MEG, MNano-Silica 0.5%, MNano-Silica 0.75%, and MNano-Silica 1% were used as impregnation solutions. The impregnation method was started with 0.5 bar of vacuum for 60 min, followed by 2.5 bar of pressure for 120 min. The dimensional stability, density, and characterization of the samples were studied through the use of scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results show that the treatment had a significant effect on the dimensional stability and density of sengon wood. Alterations in the morphology of treated sengon wood were observed through the full coverage of the pits on the vessel walls (SEM analysis results) and the detection of ethylene (FTIR analysis results) and silica (XRD and FTIR analysis results). Overall, the 0.75% MNano-Silica treatment was the most optimal treatment for increasing the dimensional stability and density of 5-year-old sengon wood.

2013 ◽  
Vol 448-453 ◽  
pp. 3041-3045
Author(s):  
Fei Bi ◽  
Xiang Ting Dong ◽  
Jin Xian Wang ◽  
Gui Xia Liu ◽  
Wen Sheng Yu

PVP/[Y(NO3)3+Al (NO3)3] composite nanobelts were fabricated via electrospinning combined with sol-gel process and novel structure of Y3Al5O12(denoted as YAG for short) nanobelts have been obtained after calcination of the relevant composite nanobelts. The structural properties were characterized by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). XRD analysis indicated that the composite nanobelts were amorphous, and YAG nanobelts were cubic in structure with space group Ia3d. FTIR analysis manifested that pure YAG nanobelts were formed at 900oC. SEM analysis and histograms revealed that the width of the composite nanobelts and YAG nanobelts were 3.5 μm and 2.4 μm, and the thickness were 240 nm and 112 nm, respectively, under the 95% confidence level. The formation mechanism of YAG nanobelts was discussed in detail.


2020 ◽  
Vol 10 (2) ◽  
pp. 48-52
Author(s):  
Muhammad Navis Rofii ◽  
Ragil Widyorini ◽  
Ganis Lukmandaru

The aim of this study was to investigate the effect of gum rosin impregnation upon a low quality young teak wood in order to enhance its quality. The main objective of the treatment was to enhance the dimensional stability, as well as strength and to reduce the hygroscopicity. A 15-years old thinned teak wood (Tectona grandis L.f.) and gum rosin from Pinus merkusii Jungh. et de Vries were used for wood modification treatment by impregnation. Three kinds of non-polar solvents, i.e. turpentine oil, petroleum oil and n-hexane-, were used to make gum rosin solution. The results indicated that gum rosin impregnation did not markedly enhance the quality of young teak wood in terms of either dimensional stability or hygroscopicity; however, a little enhancement was delivered by using 15% gum rosin solution with n-hexane as the solvent. The treatment with petroleum oil solvent (at concentration of 7.5%) and at 15% concentration with n-hexane solvent resulted in highest bending properties. The highest bonding strength in dry condition was resulted by treatment with turpentine oil solvent.


1992 ◽  
Vol 287 ◽  
Author(s):  
Patricio Toro ◽  
Oscar Wittke

ABSTRACTSi3N4 whiskers are found through SEM analysis of powder obtained by carbothermal reduction of calcined Chilean rice husks. X-ray and FTIR analysis showed that the ceramic material was mainly α-Si3N4. A stable aqueous suspension with 30 or 40 wt% Si3N4 was obtained at pH = 8.5. A maximum viscosity at pH = 4.0 and low rpm was also observed and this rheological behavior is consistent with the zeta potential data. An irregular flow behavior near pH 4.0 shows a decrease in viscosity that is related to active impurities as detected by potentiometric titrations.These rheological studies conducted allowed production of a Si3N4 green ceramic body measuring 170 × 25 × 5 mm formed by slip casting. The optimal aqueous suspension of powder contained the following: 17.0 g Si3N4, 1.0 g Cu2O, 1.3 g bentonite, and 20.0 g water.


2018 ◽  
Vol 25 (01) ◽  
pp. 1850041 ◽  
Author(s):  
FATEMEH GHASEMI ◽  
SALIMEH KIMIAGAR ◽  
MOZHGAN SHAHBAZI ◽  
HOSSEIN VOJOUDI

Graphene oxide (GO) and GO-TiO2 nanocomposite was produced then reduced under pulse laser irradiation (RGO–TiO[Formula: see text]. Basic blue 41 (bb41) dye was removed from aqueous solutions by using RGO–TiO2 nanocomposites. The UV–Vis absorption and FTIR analysis were utilized to confirm the reduction of GO-TiO2 to RGO–TiO2. The results showed complete reduction of GO. X-ray diffraction (XRD), Raman spectra and scanning electron microscopy (SEM) analysis were applied to approve the RGO–TiO2 nanocomposite structure. The effect of pH on the bb41 removal by RGO–TiO2 was studied varying the pH from 1 to 11. The optimum pH and adsorbent dosage were found to be 9 and 0.2[Formula: see text]g/L with 98% efficiency, respectively. The calculated coefficients demonstrated that the Langmuir model was fixed to the experimental data. The results indicated that RGO–TiO2 could be engaged as an exceptional sorbent to remove bb41 dye which is in aqueous solution.


Author(s):  
Parisa Sadeghpour ◽  
Mohammad Haghighi ◽  
Mehrdad Esmaeili

Aim and Objective: Effect of two different modification methods for introducing Ni into ZSM-5 framework was investigated under high temperature synthesis conditions. The nickel successfully introduced into the MFI structures at different crystallization conditions to enhance the physicochemical properties and catalytic performance. Materials and Methods: A series of impregnated Ni/ZSM-5 and isomorphous substituted NiZSM-5 nanostructure catalysts were prepared hydrothermally at different high temperatures and within short times. X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray (EDX), Brunner, Emmett and Teller-Barrett, Joyner and Halenda (BET-BJH), Fourier transform infrared (FTIR) and Temperature-programmed desorption of ammonia (TPDNH3) were applied to investigate the physicochemical properties. Results: Although all the catalysts showed pure silica MFI–type nanosheets and coffin-like morphology, using the isomorphous substitution for Ni incorporation into the ZSM-5 framework led to the formation of materials with lower crystallinity, higher pore volume and stronger acidity compared to using impregnation method. Moreover, it was found that raising the hydrothermal temperature increased the crystallinity and enhanced more uniform incorporation of Ni atoms in the crystalline structure of catalysts. TPD-NH3 analysis demonstrated that high crystallization temperature and short crystallization time of NiZSM-5(350-0.5) resulted in fewer weak acid sites and medium acid strength. The MTO catalytic performance was tested in a fixed bed reactor at 460ºC and GHSV=10500 cm3 /gcat.h. A slightly different reaction pathway was proposed for the production of light olefins over impregnated Ni/ZSM-5 catalysts based on the role of NiO species. The enhanced methanol conversion for isomorphous substituted NiZSM-5 catalysts could be related to the most accessible active sites located inside the pores. Conclusion: The impregnated Ni/ZSM-5 catalyst prepared at low hydrothermal temperature showed the best catalytic performance, while the isomorphous substituted NiZSM-5 prepared at high temperature was found to be the active molecular sieve regarding the stability performance.


Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 553
Author(s):  
Mansurbek Urol ugli Abdullaev ◽  
Sungjune Lee ◽  
Tae-Wan Kim ◽  
Chul-Ung Kim

Among the zeolitic catalysts for the ethylene-to-propylene (ETP) reaction, the SSZ-13 zeolite shows the highest catalytic activity based on both its suitable pore architecture and tunable acidity. In this study, in order to improve the propylene selectivity further, the surface of the SSZ-13 zeolite was modified with various amounts of tungsten oxide ranging from 1 wt% to 15 wt% via a simple incipient wetness impregnation method. The prepared catalysts were characterized with several analysis techniques, specifically, powder X-ray diffraction (PXRD), Raman spectroscopy, temperature-programmed reduction of hydrogen (H2-TPR), temperature-programmed desorption of ammonia (NH3-TPD), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and N2 sorption, and their catalytic activities were investigated in a fixed-bed reactor system. The tungsten oxide-modified SSZ-13 catalysts demonstrated significantly improved propylene selectivity and yield compared to the parent H-SSZ-13 catalyst. For the tungsten oxide loading, 10 wt% loading showed the highest propylene yield of 64.9 wt%, which was 6.5 wt% higher than the pristine H-SSZ-13 catalyst. This can be related to not only the milder and decreased strong acid sites but also the diffusion restriction of bulky byproducts, as supported by scanning transmission electron microscopy-energy dispersive X-ray spectroscopy (STEM-EDS) observation.


2020 ◽  
Vol 18 (1) ◽  
pp. 399-411
Author(s):  
Eman Alzahrani

AbstractA unique method was used to synthesize extremely stable silver stearate nanoparticles (AgStNPs) incorporated in an organic-based monolith. The facile strategy was then used to selectively isolate hemeproteins, myoglobin (Myo) and hemoglobin (Hb). Ethyl alcohol, silver nitrate, and stearic acid were, respectively, utilized as reducing agents, silver precursors, and capping agents. The color changed to cloudy from transparent, indicating that AgStNPs had been formed. AgStNP nanostructures were then distinctly integrated into the natural polymeric scaffold. To characterize the AgStNP–methacrylate polymeric monolith and the silver nanoparticles, energy-dispersive X-ray (EDX), scanning electron microscopy (SEM), and Fourier-transform infrared (FT-IR) spectroscopy were used. The results of the SEM analysis indicated that the AgStNP–methacrylate polymeric monolith’s texture was so rough in comparison with that of the methacrylate polymeric monolith, indicating that the extraction process of the monolith materials would be more efficient because of the extended surface area of the absorbent. The comparison between the FT-IR spectra of AgStNPs, the bare organic monolith, and AgStNP–methacrylate polymeric monolith confirms that the AgStNPs were immobilized on the surface of the organic monolith. The EDX profile of the built materials indicated an advanced peak of the Ag sequence which represented an Ag atom of 3.27%. The results therefore established that the AgStNPs had been successfully integrated into the monolithic materials. Extraction efficiencies of 92% and 97% were used to, respectively, recover preconcentrated Myo and Hb. An uncomplicated method is a unique approach of both fabrication and utilization of the nanosorbent to selectively isolate hemeproteins. The process can further be implemented by using other noble metals.


Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3588
Author(s):  
Jiayi Chen ◽  
Yansong Liu ◽  
Jiayue Zhang ◽  
Yuanlin Ren ◽  
Xiaohui Liu

Lyocell fabrics are widely applied in textiles, however, its high flammability increases the risk of fire. Therefore, to resolve the issue, a novel biomass-based flame retardant with phosphorus and nitrogen elements was designed and synthesized by the reaction of arginine with phosphoric acid and urea. It was then grafted onto the lyocell fabric by a dip-dry-cure technique to prepare durable flame-retardant lyocell fabric (FR-lyocell). X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR) analysis demonstrated that the flame retardant was successfully introduced into the lyocell sample. Thermogravimetric (TG) and Raman analyses confirmed that the modified lyocell fabric featured excellent thermal stability and significantly increased char residue. Vertical combustion results indicated that FR-lyocell before and after washing formed a complete and dense char layer. Thermogravimetric Fourier-transform infrared (TG-FTIR) analysis suggested that incombustible substances (such as H2O and CO2) were produced and played a significant fire retarding role in the gas phase. The cone calorimeter test corroborated that the peak of heat release rate (PHRR) and total heat release (THR) declined by 89.4% and 56.4%, respectively. These results indicated that the flame retardancy of the lyocell fabric was observably ameliorated.


2014 ◽  
Vol 68 (5) ◽  
Author(s):  
Nabilah Zaini ◽  
Khairul Sozana Nor Kamarudin

Emission of carbon dioxide (CO2) becomes a major concern in combating issues of global warming. The strategy to reduce the concentration of CO2 could be achieved by executing carbon capture and storage (CCS) technology such as adsorption. This study presents the used of kenaf as a green source for CO2 adsorption material. The modification of MEA on kenaf is a novelty work to enhance the capacity of adsorbent since MEA has been proved to have potential in separating CO2 in industrial applications. In this work, 10 wt % of MEA has been impregnated on kenaf via wet impregnation method. The adsorption of CO2 study was conducted by passing CO2/N2 mixture in a ratio of 30:70 in a Pressure Swing Adsorption (PSA) system with a pressure up to 1.5 bar at ambient temperature. Result obtained via SEM analysis shows that the morphology of kenaf was affected after modification with MEA. However, the presence of MEA on kenaf has improved the CO2 adsorption capacity by 16 %. In addition, the adsorption equilibrium data for kenaf and MEA modified kenaf are well fitted in Freundlich isotherm model at low pressure and well fitted in Langmuir model at higher pressure. This study indicates that the introduction of MEA on kenaf could enhance the CO2 adsorption process.  


2022 ◽  
Author(s):  
Sunita Kumari ◽  
Dhirendra Singhal ◽  
Rinku Walia ◽  
Ajay Rathee

Abstract The present project proposes to utilize rice husk and maize cob husk ash in the cement to mitigate the adverse impact of cement on environment and to enhance the disposal of waste in a sustainable manner. Ternary concrete / MR concrete was prepared by using rise husk and maize cob ash with cement. For the present project, five concrete mixes MR-0 (Control mix), MR-1 (Rice husk ash 10% and MR-2.5%), MR-2 (Rice husk ash 10% and MR-5%), MR-3 (Rice husk ash 10% and MR-2.5%), MR-4 (Rice husk ash 10% and MR-2.5%) were prepared. M35 concrete mix was designed as per IS 10262:2009 for low slump values 0-25mm. The purpose is to find the optimum replacement level of cement in M35 grade ternary concrete for I – Shaped paver blocks.In order to study the effects of these additions, micro-structural and structural properties test of concretes have been conducted. The crystalline properties of control mix and modified concrete are analyzed by Fourier Transform Infrared Spectroscope (FTIR), Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). The results indicated that 10% Rice husk ash and 5% maize cob ash replaced with cement produce a desirable quality of ternary concrete mix having good compressive strength. The results of SEM analysis indicated that the morphology of both concrete were different, showing porous structure at 7 days age and become unsymmetrical with the addition of ashes. After 28 day age, the control mix contained more quantity of ettringite and became denser than ternary concrete. XRD analysis revealed the presence of portlandite in large quantity in controlled mix concrete while MR concrete had the partially hydrated particle of alite.


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