scholarly journals Observation on the Structure of Phosphate Rocks by Surface Area Measurement and X-Ray Diffraction

1969 ◽  
Vol 18 (191) ◽  
pp. 731-737
Author(s):  
Tatsuhiko NOGUCHI
Keyword(s):  
Surface Area ◽  
Area Measurement ◽  
Phosphate Rocks ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Area Measurement

scholarly journals The Effect of Using H4P2O7 as Phosphorus Source for Synthesizing Vanadyl Pyrophosphate Catalysts

2017 ◽  
Vol 6 (3) ◽  
pp. 207
Author(s):  
Y.H. Taufiq-Yap ◽  
A. Raslan ◽  
R. Irmawati
Keyword(s):  
Surface Area ◽  
Area Measurement ◽  
Bet Surface Area ◽  
Vanadyl Pyrophosphate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Area Measurement ◽  
Phosphorus Source ◽  
Temperature Programmed ◽  
Two Peaks

<p>Vanadyl pyrophosphate (VO)<sub>2</sub>P<sub>2</sub>O<sub>7</sub> catalysts synthesized via VOPO<sub>4</sub>·2H<sub>2</sub>O were investigated by using BET surface area measurement, X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Temperature-Programmed Techniques (TPD and TPRS). H<sub>3</sub>PO<sub>4</sub> and H<sub>4</sub>P<sub>2</sub>O<sub>7</sub> were used as the phosphorus source. Only pyrophosphate phase was observed for both final catalysts after 75 hours of calcination in a reaction flow of <em>n</em>-butane/air mixture (0.75% <em>n</em>-butane/air). However, catalyst derived from H<sub>4</sub>P<sub>2</sub>O<sub>7</sub> based preparation (denoted VPD<sub>pyro</sub>) exhibit better crystallinity and slightly higher BET surface area compared to the H<sub>3</sub>PO<sub>4</sub> based preparation (denoted VPD<sub>ortho</sub>). The nature of the oxidants for both catalysts was investigated by O<sub>2</sub>-TPD. For VPD<sub>pyro</sub>, TPD showed an oxygen peak maximum at 986 K and a shoulder at 1003 K, whereas for VPD<sub>ortho</sub>, the oxygen was desorbed as two peaks maxima at 966 and 994 K. The total amount of oxygen desorbed thermally from VPD<sub>pyro</sub> (3.60×10<sup>20</sup> atom×g<sup>-1</sup>) is higher than that obtained for VPD<sub>ortho</sub> (3.07×10<sup>20</sup> atom×g<sup>-1</sup>). VPD<sub>pyro</sub> displayed a slightly improved activity and selectivity for <em>n</em>-butane oxidation. A proper amount of V<sup>5+</sup> species may have an effect on the enhancement of the catalytic activity.</p>

Preparation and Characterization of Flowerlike Nickel Oxide

2011 ◽  
Vol 121-126 ◽  
pp. 1044-1048
Author(s):  
Chang Yu Li ◽  
Shou Xin Liu ◽  
Li Li Liu
Keyword(s):  
Nickel Oxide ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Area Measurement ◽  
Simple Liquid ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Area Measurement

Flowerlike nickel oxide was synthesized by a simple liquid-phase process to obtain the hydroxide precursor and then calcined to form the nickel oxide. The precursor and the nickel oxide were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TG) , the scanning electron microscope(SEM) and Brunauer–Emmett–Teller-specific surface area measurement. The results indicated α-Nickel hydroxide was transferred to NiO with a cubic crystalline structure after being calcined at 450 °C; the NiO still kept the morphology of the precursors and the specific surface area of the NiO was 125.2m2/g.

scholarly journals Structuring of ZnTiO3/TiO2 Adsorbents for the Removal of Methylene Blue, Using Zeolite Precursor Clays as Natural Additives

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 898
Author(s):  
Ximena Jaramillo-Fierro ◽  
Silvia González ◽  
Fernando Montesdeoca-Mendoza ◽  
Francesc Medina
Keyword(s):  
Methylene Blue ◽  
Adsorption Process ◽  
Sol Gel ◽  
Area Measurement ◽  
X Ray Diffraction ◽  
Order Model ◽  
X Ray ◽  
Surface Area Measurement ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order

Adsorption is an effective method of removing harmful pollutants from air and water. In the present study, zeolites prepared by sol-gel method from two Ecuadorian clays were combined with precursor clays and the ZnTiO3/TiO2 semiconductor for adsorbing methylene blue (MB) as a water contaminant. The synthesized compounds were characterized using powder X-ray diffraction, X-ray fluorescence, scanning electron microscopy, energy dispersive X-ray, and surface area measurement. These compounds were combined to form cylindrical extrudates of 0.2 cm (diameter) and 1.0 cm (length). The adsorption characteristics of the composites were measured using batch sorption studies as a function of pH, initial concentration, and contact time. The pseudo-second-order model and the Langmuir isotherm model were better suited to the adsorption process. The equilibrium state was achieved around 180 min of adsorption, and a pH of 7 was established as the optimal operating condition. The maximum adsorption values of the dye were obtained with the composites derived from G-Clay, whose average adsorption capacity was 46.36 mg g−1, in contrast with composites derived from R-Clay, whose average adsorption value was 36.24 mg g−1. The results reflect that synthesized composites could be used potentially for the removal of cationic dye from wastewater.

Research of SO2 Resistance of MnOx Catalyst Modified by Ce for Low Temperature SCR with NH3

2011 ◽  
Vol 356-360 ◽  
pp. 529-532 ◽  
Author(s):  
Yan Wang ◽  
Liu Yang ◽  
Wei Ping Liao ◽  
Fei Wang
Keyword(s):  
Low Temperature ◽  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Area Measurement ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermal Gravimetry ◽  
Surface Area Measurement ◽  
Low Temperature Scr

Two catalysts, MnOx and ceria modified MnOx were prepared by deposition-precipitation method and used for low-temperature selective catalytic reduction (SCR) with NH3in the presence of SO2. The catalysts were characterized by X-ray diffraction (XRD), surface area measurement (BET) and thermal gravimetry analysis(TG). The deactivation of MnOx and MnOx-CeO2by SO2was observed during SCR process. It was found that the resistance to SO2could be greatly enhanced for Ce modified MnOx. It was because that the formation of Mn(SO4)x was prevented and the depositions of (NH4)2SO4and NH4HSO4were significantly inhibited with the doping of ceria.

scholarly journals Catalytic hydrogenation of n-butene with nanosized Pt/NBCNT hybrid membranes reinforced with bacterial cellulose

2020 ◽  
Vol 56 (1) ◽  
pp. 927-935
Author(s):  
Bilal El Mrabate ◽  
Ádám Prekob ◽  
László Vanyorek ◽  
Emília Csiszár ◽  
Ferenc Kristály ◽  
...  
Keyword(s):  
Bacterial Cellulose ◽  
Area Measurement ◽  
Hybrid Membranes ◽  
X Ray Diffraction ◽  
Thin Solid Films ◽  
X Ray ◽  
Solid Films ◽  
Membrane Catalyst ◽  
Prepared Material ◽  
Surface Area Measurement

Abstract One of the main challenges in the field of heterogeneous catalysis is the involvement of thin solid films and membranes and their application in flow systems. In this regard, we report here the application of self-supported bacterial cellulose (BC) reinforced nanosized platinum (Pt)/N-doped bamboo-like carbon nanotube (NBCNT) hybrid catalyst membrane with a thickness of 35 ± 5 µm in the hydrogenation of n-butene. To synthetized the BC-NBCNT/Pt nanohybrid membrane catalyst a simple impregnation route was applied in a two-step process. As-prepared material was tested in a continuous flow system and the conversion was followed directly by using Fourier transform infrared spectroscopy. Furthermore, the fabricated films were characterized by scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy and specific surface area measurement (Brunauer–Emmett–Teller). Hydrogenation performance was studied on both single and double films. Results revealed that 97% conversion of n-butene can be achieved using these bacterial cellulose reinforced hybrid membranes. Graphic abstract

Adsorption studies of hydrogen and ethylene on cation-exchanged bentonite

Clay Minerals ◽  
2017 ◽  
Vol 52 (1) ◽  
pp. 67-73 ◽  
Author(s):  
Burcu Erdoğan Alver
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Powder Diffraction ◽  
Gas Adsorption ◽  
Adsorption Properties ◽  
Area Measurement ◽  
X Ray ◽  
Adsorption Capacities ◽  
Surface Area Measurement ◽  
Modified Forms

AbstractThe adsorption of C2H4 and H2 gases by bentonite from the Ünye region, Turkey both as raw (B) and as K+-, Li+-, Ag+- and Mg2+ -exchanged forms, was investigated using automated volumetric equipment and pressures up to 100 kPa at 273 K and 77 K, respectively. X-ray powder diffraction (XRD) and specific surface area measurement (BET) methods were employed to characterize the bentonite samples. The C2H4 and H2 gas adsorption capacities of the original and modified forms were in the ranges 1.817–0.201 mmol g−1 and 0.522–0.388 mmol g−1, respectively. The influence of salt modifications on the gas adsorption properties of bentonite is discussed.

scholarly journals Hydrochloric Acid Modification and Lead Removal Studies on Naturally Occurring Zeolites from Nevada, New Mexico, and Arizona

Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1238
Author(s):  
Garven M. Huntley ◽  
Rudy L. Luck ◽  
Michael E. Mullins ◽  
Nick K. Newberry
Keyword(s):  
New Mexico ◽  
Surface Area ◽  
Bet Surface Area ◽  
Lead Removal ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Naturally Occurring ◽  
27Al Mas Nmr ◽  
Modified Zeolites

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.

Efficient adsorption of chlorpyrifos onto modified activated carbon by gamma irradiation; a plausible adsorption mechanism

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohamed S. Yahia ◽  
Ahmed S. Elzaref ◽  
Magdy B. Awad ◽  
Ahmed M. Tony ◽  
Ahmed S. Elfeky
Keyword(s):  
Gamma Irradiation ◽  
Area Measurement ◽  
Maximum Adsorption Capacity ◽  
X Ray Diffraction ◽  
X Ray ◽  
First Order ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Pseudo First Order ◽  
Kinetics Of

Abstract Commercial Granulated Active Carbon (GAC) has been modified using 10 Gy dose Gamma irradiation (GAC10 Gy) for increasing its ability of air purification. Both, the raw and treated samples were applied for removing Chlorpyrifos pesticide (CPF) from ambient midair. Physicochemical properties of the two materials were characterized by Fourier Transform Infrared (FT-IR) and Raman spectroscopy. The phase formation and microstructure were monitored using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), supported with Energy-Dispersive X-ray (EDX). The Surface area measurement was detected using BET particle size prosometry. Obtained outcomes showed that, the maximum adsorption capacity, given by Langmuir equations, was greatly increased from 172.712 to 272.480 mg/g for GAC and GAC10 Gy, respectively, with high selectivity. The overall removal efficiency of GAC10 Gy was notably comparable to that of the original GAC-sorbent. The present study indicated that, gamma irradiation could be a promising technique for treating GAC and turned it more active in eliminating the pesticides pollutants from surrounding air. The data of equilibrium has been analyzed by Langmuir and Freundlich models, that were considerably better suited for the investigated materials than other models. The process kinetics of CPF adsorbed onto both tested carbon versions were found to obey the pseudo first order at all concentrations with an exception at 70 mg/l using GAC, where, the spontaneous exothermic adsorption of Chlorpyrifos is a strong function for the pseudo-first order (PFO) and pseudo second order (PSO) kinetics.

Physico-Chemical and Morphological Changes of Sayong Kaolinite Clay Treated with Sulphuric Acid for Enzyme Immobilization

2013 ◽  
Vol 832 ◽  
pp. 589-595 ◽  
Author(s):  
N.A. Edama ◽  
A. Sulaiman ◽  
K.H. Ku Hamid ◽  
M.N. Muhd Rodhi ◽  
Mohibah Musa ◽  
...  
Keyword(s):  
Surface Area ◽  
Sulphuric Acid ◽  
Enzyme Immobilization ◽  
Morphological Changes ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
Kaolinite Clay ◽  
X Ray ◽  
Mineral Oxides ◽  
Physico Chemical

This study analyzed the effects of sulphuric acid (H2SO4) treatment on pysico-chemical properties and morphological changes of clay obtained from Sg. Sayong, Perak. The clay was ground and sieved to <150μm and treated with different concentrations of H2SO4. The treatment was completed by refluxing the clay with different concentration of H2SO4 (1M, 5M and 10M ) at 100 °C for 4 hours and followed by calcination at 500 °C for 1 hour. The physic-chemical properties and morphological changes of the untreated and treated clay were compared using Surface Area Analyser, X-Ray Diffraction (XRD), Field Emission Scanning Electron Micrograph (FESEM), X-Ray Diffraction (XRD) and Fourier Transformed Infrared Spectroscopy (FTIR). The results showed that acid treatment of 5M increased the surface area from 25 m2/g to 75 m2/g and the pore volume increased from 0.1518 cc/g to 0.3546 cc/g. The nanopore size of the clay decreased from 24.8 nm to 19.4 nm after treated with acid. This can be explained due to the elimination of the exchangeable cations and generation of microporosity. The results of XRF showed SiO2 increased from 58.34% to 74.52% and Al2O3 reduced from 34.6% to 18.31%. The mineral oxides such as Fe2O3, MgO, CaO, K2O and TiO2 also reduced. This concluded that H2SO4 treatment has led to significant removal of octahedral Al3+, Fe3+ cations and other impurities. In conclusion, this study showed the physico-chemical properties and morphology of Sayong clay were improved once treated with H2SO4 and therefore suggests better supporting material for enzyme immobilization.

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