An XRD and Fourier-transformed infrared spectroscopy investigation of single and mixed γ-alumina and thorium oxide

Dabbagh, Hossein A.; Yalfani, Mohammadsadegh; Davis, Burtron H.

doi:10.1016/j.molcata.2005.03.037

Cited by 18 publications

(4 citation statements)

References 32 publications

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“…The diffraction pattern of TMPGZDC represents an increase in amorphous nature, which may increase the adsorption capacity. The XRD patterns of Th(IV)-TMPGZDC show increased crystallinity and diffraction peaks of ThO 2 at 28° and 55°, which confirm the adsorption process …”

Section: Resultsmentioning

confidence: 63%

“…The XRD Industrial & Engineering Chemistry Research ARTICLE patterns of Th(IV)-TMPGZDC show increased crystallinity and diffraction peaks of ThO 2 at 28°and 55°, which confirm the adsorption process. 33 The FTIR spectra of Cellulose, ZDC, PGZDC, TMPGZDC, and Th(IV)-TMPGZDC (Figure 4) show absorption bands at 3344, 2900, and 1640 cm À1 because of hydrogen bonded OÀH stretching vibration, CÀH stretching from the ÀCH 2 group and ÀOH bending vibration, respectively. The bands at 1426, 1382, and 1315 cm À1 are due to the bending vibration of CÀH stretching from the ÀCH 2 group.…”

Section: Sorption Experimentsmentioning

confidence: 99%

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Thorium(IV) Removal and Recovery from Aqueous Solutions using Tannin-Modified Poly(glycidylmethacrylate)-Grafted Zirconium oxide Densified Cellulose

Anirudhan

Rejeena

2011

Ind. Eng. Chem. Res.

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A novel adsorbent, tannin-modified poly(glycidylmethacrylate)-grafted zirconium oxide-densified cellulose (TMPGZDC) was synthesized by graft copolymerization reaction of glycidylmethacrylate onto zirconium oxide densified cellulose (ZDC) in the presence of N,N 0 -methylenebisacrylamide as cross-linker followed by tannin immobilization, and well characterized. The adsorption efficiency of TMPGZDC toward thorium(IV) from aqueous solutions was studied at different optimized conditions. The optimum pH for maximum adsorption was found to be 5.5 with the adsorption percentage of 99.2% for an initial concentration of 10 mg/L. Equilibrium was achieved within 2 h. The kinetic data were found to follow pseudo-second-order model, which assumes the presence of chemisorption. The temperature dependence indicates an exothermic process. The well agreement of equilibrium data with Langmuir isotherm and Redlich-Peterson isotherm models confirms the monolayer coverage of Th(IV) onto TMPGZDC surface and the maximum adsorption capacity was found to be 96.7 mg/g. Complete removal of Th(IV) from simulated seawater was possible with an adsorbent dosage of 3.0 g/L. Spent adsorbent was effectively degenerated with 0.1 M HNO 3 . The present investigation shows that TMPGZDC is a promising adsorbent for the removal and recovery of Th(IV) from aqueous solutions.

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Section: Resultsmentioning

confidence: 63%

Section: Sorption Experimentsmentioning

confidence: 99%

Thorium(IV) Removal and Recovery from Aqueous Solutions using Tannin-Modified Poly(glycidylmethacrylate)-Grafted Zirconium oxide Densified Cellulose

Anirudhan

Rejeena

2011

Ind. Eng. Chem. Res.

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“…The FTIR spectra of bohemite (AlO(OH)) normally show a broad band in the spectral range of (3300 -3500) cm -1 which is assigned to -OH stretching vibration due to hydrogen bonding formation of this group in the aluminium oxy-hydroxide solid [10]. In this region the intensity and the width of the peak, are related to the amount of -OH group, because of the number of H 2 O molecules and consequently hydrogen bond generation [11].The peak at 1635 cm -1 [12] is assigned to the bending mode of water molecules in the bohemite structure.The above mentioned (3300 -3500) cm -1 and 1635 cm -1 peaks appear in gamma phase of alumina too, but with lower intensity and less width for vibrational stretching and very short intensity for bending mode with respect to the bohemite phase.The vibrational mode of Al-O-Al and Al-O for both bohemite and γ-alumina phases are similar with only very slight difference.…”

Section: Resultsmentioning

confidence: 99%

Infrared Spectroscopy Studies on sol-gel prepared alumina Powders

Tafreshi¹,

Khanghah²

2015

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Gamma-alumina fine particles were synthesized by sol-gel process. Aluminum tri-sec-butoxide (ATB), anhydrous ethyl alcohol (EtOH), water (H 2 O) and hydrochloric acid (HCl) were used as starting materials. Different samples were synthesized with EtOH/ATB = 60/1, HCl/ATB = 0.08/1 and H 2 O/ATB = 1/1 ratios and calcined at different temperatures. Molar ratios of H 2 O/ATB (from 1 to 25) and HCl/ATB (from 0.08 to 0.4) were changed for some other samples, during the synthesizing process. The products were characterized by both XRD and FTIR measurements. Studies were carried out on the effect of calcination temperature and change of H 2 O/ATB and HCl/ATB ratios on structure and processes involved in phase transformations.

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“…However, with a reference temperature of 300°C for the synthesis procedure, this may contribute to less resolved XRD diffraction patterns as observed in the synthesis of flowerlike c-alumina grown by precipitation on quartz surface at high temperatures [17]. In the case of the synthesis of c-alumina by hydrolysis of aluminum isopropoxide, Dabbagh et al [46] reported that the broadness of the peaks can be also explained by the random distribution of aluminum ions over the tetrahedron sites of the spinel lattice [47].…”

Section: Materials Characterizationmentioning

confidence: 99%

A new route for the synthesis of self-acidified and granulated mesoporous alumina catalyst with superior Lewis acidity and its application in cumene conversion

et al. 2019

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Self-acidified and granulated mesoporous alumina (SAGMA) with dendritic-like microscopic shape was prepared by a new route that involves: (a) direct dehydration of AlCl 3 (in the presence of capping petroleum wax), and (b) oxi-dation of intermediary AlCl 3 -nanorods. The AlCl 3 solution dispersed in petro-leum wax (capping media) was firstly dehydrated at 100 °C under inert atmosphere for manufacturing anhydrous AlCl 3 -nanorods (length: 50-100 nm; diameter: 5-10 nm). In a second step, this support was oxidized into c-alumina at 300 °C, under air atmosphere. In the course of the manufacturing process, released chlorine was deposited at the surface of the nanorods (more specifically during the oxidation step). The binding of chlorine (5.35%, w/w at the surface) onto c-alumina was demonstrated by both electron dispersive X-ray analysis (SEM-EDX) and Fourier-transformed infrared spectroscopy. Specific surface area reached 230 m 2 g -1 ; the average pore size was 7.8 nm. Material charac-terization was completed by measuring the surface acidity through both tem-perature-programmed desorption and pyridine desorption. The morphology and the phase structure were investigated using scanning electron microscopy and X-ray diffraction analysis, respectively. SAGMA (c-alumina) can be described as a strong Lewis (1.713 mmol g -1 ; i.e., about 93% of total acid sites) and Brønsted acid catalyst supported on a mesoporous structure (self-granular size of 177-250 lm). Cumene conversion (through a dealkylation pathway) was tested on SAGMA: maximum catalytic activity reached 87% at 300 °C. The conversion is highly selective: the reaction produces benzene and only traces of ethylbenzene (mass fraction below 4% compared to benzene). Apart from this good catalytic efficiency, the material is characterized by its strong stability in terms of both catalytic activity (loss less than 2%, for optimum conditions) and surface acidity (loss less than 3%), even for long reaction times (i.e., 24 h) under severe conditions (i.e., T 300 °C). This new material, easily manufactured, is characterized by high efficiency and selectivity in cumene conversion into benzene, associated with high acidity and good stability

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An XRD and Fourier-transformed infrared spectroscopy investigation of single and mixed γ-alumina and thorium oxide

Cited by 18 publications

References 32 publications

Thorium(IV) Removal and Recovery from Aqueous Solutions using Tannin-Modified Poly(glycidylmethacrylate)-Grafted Zirconium oxide Densified Cellulose

Thorium(IV) Removal and Recovery from Aqueous Solutions using Tannin-Modified Poly(glycidylmethacrylate)-Grafted Zirconium oxide Densified Cellulose

Infrared Spectroscopy Studies on sol-gel prepared alumina Powders

A new route for the synthesis of self-acidified and granulated mesoporous alumina catalyst with superior Lewis acidity and its application in cumene conversion

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