scholarly journals Influence of Pyrolysis Parameters Using Microwave toward Structural Properties of ZnO/CNS Intermediate and Application of ZnCr2O4/CNS Final Product for Dark Degradation of Pesticide in Wet Paddy Soil

2021 ◽  
Vol 5 (3) ◽  
pp. 58
Author(s):  
Tutik Setianingsih ◽  
Danar Purwonugroho ◽  
Yuniar Ponco Prananto

Pesticide is a pollution problem in agriculture. The usage of ZnCr2O4/CNS and H2O2 as additive in liquid fertilizer has potency for catalytic pesticide degradation. Colloid condition is needed for easy spraying. Rice husk and sawdust were used as carbon precursor and ZnCl2 as activator. The biomass–ZnCl2 mixtures were pyrolyzed using microwave (400–800 W, 50 min). The products were dispersed in water by blending then evaporated to obtain ZnO/CNS. The composites were reacted with KOH, CrCl3·6H2O, more ZnCl2, and little water by microwave (600 W, 5 min). The ZnCr2O4/CNS and H2O2 were used for degradation of buthylphenylmethyl carbamate (BPMC) in wet deactivated paddy soil. TOC was measured using TOC meter. The FTIR spectra of the ZnO/CNS composites indicated the completed carbonization except at 800 W without ZnCl2. The X-ray diffractograms of the composites confirmed ZnO/CNS structure. SEM images showed irregular particle shapes for using both biomass. ZnCr2O4/CNS structure was confirmed by XRD as the final product with crystallite size of 74.99 nm. The sawdust produced more stable colloids of CNS and ZnO/CNS composite than the rice husk. The pyrolysis without ZnCl2 formed more stable colloid than with ZnCl2. The ZnCr2O4/CNS from sawdust gave better dark catalytic degradation of BPMC than from rice husk, i.e., 2.5 and 1.6 times larger for 400 and 800 W pyrolysis, respectively.

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1349
Author(s):  
Tutik Setianingsih ◽  
Bambang Susilo ◽  
Siti Mutrofin ◽  
Bambang Ismuyanto ◽  
Andreas Novan Endaryana ◽  
...  

In this research work, MFe2O4/CNS was prepared using the hydrothermal–microwave method. The influence of cations (M) toward functional groups of composites and their performance in pesticide degradation were studied. Rice husk was pyrolyzed hydrothermally (200 °C, 6 h) and by microwave (800 W, 40 min). Each product was mixed with MCl2 (Zn, Ni, Mn), FeCl3, KOH, and water, and calcined (600 °C, 15 min) to obtain a composite. Characterization by XRD confirmed the MFe2O4/CNS structure. The FTIR spectra of the composites showed different band sharpness related to C-O and M-O. A mixture of dried paddy farm soil, composite, BPMC (buthylphenylmethyl carbamate) pesticide solution (0.25%), and H2O2 solution (0.15%) was kept under dark conditions for 48 h. The solution above the soil was filtered and measured with a UV-Vis spectrophotometer at 217 nm. Applications without the composite and composite–H2O2 were also conducted. The results reveal that dark BPMC degradation with the composite was 7.5 times larger than that without the composite, and 2.9 times larger than that without the composite–H2O2. There were no significantly different FTIR spectra of the soil, soil–BPMC, soil–BPMC-H2O2, and soil–BPMC-H2O2 composite and no significantly different X-ray diffractograms between the soil after drying and soil after application for pesticide degradation using the composite.


2012 ◽  
Vol 727-728 ◽  
pp. 1158-1163
Author(s):  
Felipe Antunes Santos ◽  
Claudinei dos Santos ◽  
Durval Rodrigues Júnior ◽  
Daltro Garcia Pinatti ◽  
Erika Davim ◽  
...  

The crystallization process of lithium disilicate glass-ceramic with SiO2 from rice husk silica replacing the high-purity SiO2 starting powder has been investigated in this work. Glasses were developed at the stoichiometric composition of 66%.molSiO2:33%.molLiO2 using commercial SiO2 and the one obtained by thermochemical treatment of rice husk. The influence of rice husk-SiO2 on crystallization process to different granulometry, microstructure and kinetic behavior was determined and discussed. Investigations were carried out by means of differential thermal analysis (DTA), X-ray fluorescence (XRF), X-ray diffractometry (XRD) and scanning electron microscopy (SEM). Amorphous and transparent glasses were obtained after melting. The lithium disilicate glass-ceramic crystallization peaks (Tp) are between 550 to 660°C to different granulometry (<63μm, 63μm < x < 250μm and 1mm < x < 2mm) and DTA heat rates (5; 10; 15; and 20°C/min) in both glasses from different silica sources, and the formed phase was Li2Si2O5 as the crystalline phase after DTA thermal analysis as XRD confirmation. Improve in mechanical properties were estimated by morphological analysis of the microstructure modification in increasing the heat treatments temperature by SEM. The increase of glass substitution for crystalline phase was also observed with SEM images to both glass-ceramics from different silica sources.


2020 ◽  
Vol 856 ◽  
pp. 198-204
Author(s):  
Ravisara Chainaruprasert ◽  
Thirawudh Pongprayoon

Biogenatic nanosilica was synthesized by sol-gel method from rice husk ash. The batch reactor was designed to scaling-up from laboratory scale approximately 5 g to approximately 300 g of the feed raw materials. The synthesized silica products from lab-scale vessel and scaling up designed batch reactor were compared with percent yield and nanoparticle size. The particles of nanosilica from both scale productions were characterized by X-ray Fluorescence (XRF), X-ray Diffraction (XRD) and Scanning Electron Microscope (SEM). The size and size distribution of nanoparticles were estimated by ImageJ software in 100 points from SEM images. The synthesized nanosilica particles from laboratory vessel and designed reactor were the same of % yield production, components, physical structure, silica purity, and nanoparticle size. Moreover, the commercial nanosilica was analyzed for comparison.


2018 ◽  
Vol 4 (3) ◽  
pp. 571-575
Author(s):  
T. Kirushanthi ◽  
Thusitha N. Etampawala ◽  
Dilhara Edirisinghe ◽  
Jagath Pitawala ◽  
D.R. Ratnaweera

Agro-industrial waste has become a major environmental issue in most parts of the world. Rice husk is one of the major agricultural wastes especially in Asian countries. It is currently thrown away into landfills or rarely use as an alternative energy source, which in turn produce another waste, rice husk ash (RHA). Silica is the major component in well-burnt RHA. This work was aimed to evaluate the feasibility of utilizing silica extracted from RHA and another industrial waste, used tyre treads, with natural rubber to develop composite with enhanced mechanical properties especially for flooring products such as rugs, pavement blocks, door mats, etc. In this work extracted silica was characterized using Fourier-transform infrared spectroscopy, X-ray diffractometry (XRD), X-ray fluorescence spectroscopy (XRF) and scanning electron microscopy (SEM). The SEM images confirmed that the extracted silica is in the nanometer to sub-micrometer length scale in size. Further our results confirmed that extracted silica has comparable chemical composition and amorphous nature as commercially used silica in rubber compounding. Composites were first formulated using crumb rubber to identify the optimum crumb rubber loading. It is found that 25 phr of crumb rubber provides the optimal mechanical properties. Finally, extracted silica was incorporated to 25 phr crumb rubber loaded composite to further reinforcement. SEM images confirm that 10 phr of silica have enhanced matrix-filler interactions to produce continuous structure, which was not observed in crumb rubber loaded rubber composite.


2013 ◽  
Vol 717 ◽  
pp. 58-61
Author(s):  
Khanidtha Jantasom ◽  
Potjanee Somrud ◽  
Suttinart Noothongkeaw ◽  
Ki Seok An ◽  
Udom Tipparach ◽  
...  

Nanostructures materials were prepared from rice husk ash by carbon charcoal assisted. The rice husk ash mixed with coconut shell charcoal and Cu-Sn powder as the source materials. The mixtures materials were heated at 1100 °C under atmosphere of nitrogen with flow rate of 1 L/min. After the temperature was cool down, the prepared products were characterized by the stereo microscope, scanning electron microscope (SEM) and X-ray diffraction (XRD). The SEM images showed nanostructures materials such as nanoparticles, nanorods and nanowires. The XRD patterns indentified that the consisted of nanostructures materials were SiO2-CuO phase.


Author(s):  
J.D. Geller ◽  
C.R. Herrington

The minimum magnification for which an image can be acquired is determined by the design and implementation of the electron optical column and the scanning and display electronics. It is also a function of the working distance and, possibly, the accelerating voltage. For secondary and backscattered electron images there are usually no other limiting factors. However, for x-ray maps there are further considerations. The energy-dispersive x-ray spectrometers (EDS) have a much larger solid angle of detection that for WDS. They also do not suffer from Bragg’s Law focusing effects which limit the angular range and focusing distance from the diffracting crystal. In practical terms EDS maps can be acquired at the lowest magnification of the SEM, assuming the collimator does not cutoff the x-ray signal. For WDS the focusing properties of the crystal limits the angular range of acceptance of the incident x-radiation. The range is dependent upon the 2d spacing of the crystal, with the acceptance angle increasing with 2d spacing. The natural line width of the x-ray also plays a role. For the metal layered crystals used to diffract soft x-rays, such as Be - O, the minimum magnification is approximately 100X. In the worst case, for the LEF crystal which diffracts Ti - Zn, ˜1000X is the minimum.


Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1238
Author(s):  
Garven M. Huntley ◽  
Rudy L. Luck ◽  
Michael E. Mullins ◽  
Nick K. Newberry

Four naturally occurring zeolites were examined to verify their assignments as chabazites AZLB-Ca and AZLB-Na (Bowie, Arizona) and clinoptilolites NM-Ca (Winston, New Mexico) and NV-Na (Ash Meadows, Nevada). Based on powder X-ray diffraction, NM-Ca was discovered to be mostly quartz with some clinoptilolite residues. Treatment with concentrated HCl (12.1 M) acid resulted in AZLB-Ca and AZLB-Na, the chabazite-like species, becoming amorphous, as confirmed by powder X-ray diffraction. In contrast, NM-Ca and NV-Na, which are clinoptilolite-like species, withstood boiling in concentrated HCl acid. This treatment removes calcium, magnesium, sodium, potassium, aluminum, and iron atoms or ions from the framework while leaving the silicon framework intact as confirmed via X-ray fluorescence and diffraction. SEM images on calcined and HCl treated NV-Na were obtained. BET surface area analysis confirmed an increase in surface area for the two zeolites after treatment, NM-Ca 20.0(1) to 111(4) m2/g and NV-Na 19.0(4) to 158(7) m2/g. 29Si and 27Al MAS NMR were performed on the natural and treated NV-Na zeolite, and the data for the natural NV-Na zeolite suggested a Si:Al ratio of 4.33 similar to that determined by X-Ray fluorescence of 4.55. Removal of lead ions from solution decreased from the native NM-Ca, 0.27(14), NV-Na, 1.50(17) meq/g compared to the modified zeolites, 30 min HCl treated NM-Ca 0.06(9) and NV-Na, 0.41(23) meq/g, and also decreased upon K+ ion pretreatment in the HCl modified zeolites.


2021 ◽  
Vol 19 (1) ◽  
pp. 745-754
Author(s):  
Khoirina Dwi Nugrahaningtyas ◽  
Eddy Heraldy ◽  
Rachmadani ◽  
Yuniawan Hidayat ◽  
Indriana Kartini

Abstract The properties of three types of CoMo/USY catalysts with different synthesized methods have been studied. The sequential and co-impregnation methods followed by activation using calcination and reduction process have been conducted. The properties of the catalysts were examined using Fourier-transform-infrared (FTIR) spectroscopy, X-ray diffraction (XRD) with refinement, and surface area analyzer (SAA). The FTIR spectrum study revealed the enhanced intensity of its Bronsted acid site, and the XRD diffractogram pattern verified the composition of pure metals, oxides, and alloys in the catalyst. The SAA demonstrated the mesoporous features of the catalyst. Scanning electron microscopy showed an irregular particle morphology. Additional analysis using the transmission electron microscopy indicated that the metal has successfully impregnated without damaging the USY structure.


Insects ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 895
Author(s):  
Jing Xu ◽  
Kaihui Zhang ◽  
Andrew G. S. Cuthbertson ◽  
Cailian Du ◽  
Shaukat Ali

Nanotechnology has clear potential in the development of innovative insecticidal products for the biorational management of major insect pests. Metal-based nanoparticles of different microbial pest control agents have been effective against several pests. Synthesis of Beauveria brongniartii based Fe0 nanoparticles (Fe0NPs) and their bio-efficacy against Spodoptera litura was observed during this study. Beauveria brongniartii conidia were coated with Fe0NPs and characterized by applying a selection of different analytical techniques. Ultraviolet (UV) spectroscopy showed the characteristic band of surface plasmon at 430 nm; Scanning electron microscopy (SEM) images showed spherical shaped nanoparticles with a size ranging between 0.41 to 0.80 µm; Energy-dispersive X-ray (EDX) spectral analysis revealed characteristic Fe peaks at 6.5 and 7.1 Kev; the X-ray diffractogram showed three strong peaks at 2θ values of 45.72°, 64.47°, and 84.05°. The bioassay studies demonstrated that mortality of 2nd instar S. litura larvae following Fe0NPs treatment increased with increasing concentrations of Fe0NPs at different time intervals. The median lethal concentration (LC50) values of Fe0NPs against S. litura after seven days of fungal treatment was 59 ppm, whereas median survival time (LT50) values for 200 and 500 ppm concentrations of Fe0NPs against S. litura seven days post-treatment were 5.1 and 2.29 days, respectively. Beauveria brongniartii-Fe0NPs caused significant reductions in feeding and growth parameters (relative growth rate, relative consumption rate, and efficiency of conversion of ingested food) of S. litura. Beauveria brongniartii Fe0NPs induced reduction in glutathione-S-transferase activities throughout the infection period whereas activities of antioxidant enzymes decreased during later periods of infection. These findings suggest that B. brongniartii Fe0NPs can potentially be used in biorational S. litura management programs.


Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 931
Author(s):  
Ioana-Codruţa Mirică ◽  
Gabriel Furtos ◽  
Ondine Lucaciu ◽  
Petru Pascuta ◽  
Mihaela Vlassa ◽  
...  

The aim of this research was to develop new electrospun membranes (EMs) based on polycaprolactone (PCL) with or without metronidazole (MET)/nano-hydroxyapatite (nHAP) content. New nHAP with a mean diameter of 34 nm in length was synthesized. X-ray diffraction (XRD) and attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR) were used for structural characterization of precursors and EMs. The highest mechanical properties (the force at maximum load, Young’s modulus and tensile strength) were found for the PCL membranes, and these properties decreased for the other samples in the following order: 95% PCL + 5% nHAP > 80% PCL + 20% MET > 75% PCL + 5% nHAP + 20% MET. The stiffness increased with the addition of 5 wt.% nHAP. The SEM images of EMs showed randomly oriented bead-free fibers that generated a porous structure with interconnected macropores. The fiber diameter showed values between 2 and 16 µm. The fiber diameter increased with the addition of nHAP filler and decreased when MET was added. New EMs with nHAP and MET could be promising materials for guided bone regeneration or tissue engineering.


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