Baeyer-Villiger Reaction of Adamantanone over Sn-Containing Hydrotalcite-Like Catalysts

2007 ◽  
Vol 119 ◽  
pp. 163-166 ◽  
Author(s):  
Zhi Qiang Yang ◽  
Sang Eon Park
Keyword(s):  
Hydrogen Peroxide ◽  
Ion Exchange ◽  
Direct Synthesis ◽  
Xrd Analysis ◽  
Catalytic Performance ◽  
X Ray Diffraction ◽  
Exchange Method ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Ion Exchange Method

Sn-containing hydrotalcite-like compounds were prepared by three different methods such as (i) direct synthesis, (ii) ion-exchange and (iii) grafting. These catalysts were proved to have framework Sn species by powder X-ray diffraction (XRD) analysis and UV-vis spectroscopy. The catalysts prepared by three methods were found to be active and selective for the liquid phase Baeyer–Villiger (BV) oxidation of admantonone using hydrogen peroxide (H2O2) as an oxidant and acetonitrile as a solvent. The Sn-hydrotalcite-like catalysts prepared by ion-exchange method exhibited better catalytic performance than the catalysts prepared by other two methods. Among the ion-exchanged hydrotalacite-like catalysts, 3% Sn ion-exchanged hydrotalcite exhibited superior activity at 30% conversion and 100% selectivity.

scholarly journals Direct oxidation of benzene to phenol catalyzed by a vanadium-substituted heteropolymolybdic acid catalyst

2006 ◽  
Vol 71 (2) ◽  
pp. 111-120 ◽  
Author(s):  
Ying Tang ◽  
Jin Zhang
Keyword(s):  
Hydrogen Peroxide ◽  
Direct Synthesis ◽  
Acid Catalyst ◽  
X Ray Diffraction ◽  
Direct Oxidation ◽  
Experimental Conditions ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Nmr Techniques ◽  
Oxidation Of Benzene

The direct synthesis of phenol by hydroxylation of benzene with hydrogen peroxide over a vanadium substituted heteropolymolybdic acid catalyst was investigated at 70 ?C. Hydrogen peroxide was used as the oxidant while 36 wt.% acetic acid was employed as the solvent. After 100 minutes, the selectivity for phenol was 93% and the yield of phenol was 10.1 %. The catalyst was characterized by elemental analysis, thermogravimetry, infrared spectroscopy, UV-Vis spectroscopy, X-ray diffraction, and 31P-NMR and 51V-NMR techniques. The experimental conditions, such as reaction temperature, the amount of hydrogen peroxide and catalyst, were investigated. The as-prepared phenol could be separated by column chromatography and was characterized by infrared and mass spectrometry.

Study on Organic Modified of Montmorillonite by Corrosion Inhibitor of Quaternary Ammonium Salts

2013 ◽  
Vol 669 ◽  
pp. 103-107 ◽  
Author(s):  
Jian Guo Sheng ◽  
Ping Zeng
Keyword(s):  
Ion Exchange ◽  
Quaternary Ammonium ◽  
Interlayer Space ◽  
Quaternary Ammonium Salts ◽  
Raw Material ◽  
Ammonium Salts ◽  
X Ray Diffraction ◽  
Exchange Method ◽  
X Ray ◽  
Ion Exchange Method

A series of organic montomorilonite were prepared by using Sodium monanorilonite(Na-MMT) as raw material and quaternary ammonium salts with different chain long as intercalation agents by the way of ion exchange method. Weightlessness experiment showed that intercalated agents could alleviate the corrosion of metal. The MMT and organic MMT (OMMT) were identified by infrared spectra (FTIR) and X-ray diffraction (XRD). The results showed that intercalation agents had intercalated into the interlayer space of MMT, and the spacing of MMT layers had increased from 1.51 nm to 2.94 nm.

Decolorization of methyl orange by green rusts with hydrogen peroxide at neutral pH

2013 ◽  
Vol 69 (2) ◽  
pp. 371-377 ◽  
Author(s):  
Yulong Lin ◽  
Caiqin Yang ◽  
Rong Xiu ◽  
Jing Wang ◽  
Yu Wei ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Methyl Orange ◽  
Xrd Analysis ◽  
Oxidation Reactions ◽  
X Ray Diffraction ◽  
Heterogeneous Fenton ◽  
X Ray ◽  
Magnetite Fe3o4 ◽  
Initial Ph ◽  
Green Rusts

Heterogeneous Fenton-like processes using green rusts (GRs) with hydrogen peroxide (H2O2) were studied to decolorize methyl orange (MO) in aqueous solution at an initial pH of 7.0. In this study, two types of crystal structure for GRs, the hydroxycarbonate GR(CO32–) (GR1) and the hydroxysulphate GR(SO42–) (GR2), were synthesized by partial oxidation of Fe(OH)2 suspension under light irradiation and distinguished by X-ray diffraction (XRD) due to different characteristic peaks. In oxidation reactions, decolorization rate of MO, bubbling air through the solution, was about 65% (experiment B), whereas, it was up to 95% in the presence of H2O2 (experiment C) within 60 min. The comparative tests of GR1 and GR2 show that the reduction capability of GR2 is stronger than GR1, which may be due to Fe(II) content and interlayer anions. XRD analysis and Fourier transform infrared spectroscopy revealed that the oxidation end products of GR2 were mainly a poorly crystallized mixture of magnetite (Fe3O4) and hydroxy ferric oxide (FeOOH). However, when GR was immediately oxidized, the weakly crystallized goethite (α–FeOOH) and lepidocrocite (γ–FeOOH) were formed for O2 and H2O2, respectively. Based on the intermediates obtained, a probable decolorization mechanism has been proposed.

scholarly journals Effect of Ag Doping on Properties of Al–Doped ZnO Nanoparticles Varies as Zn1-X-YAgxALYO

2017 ◽  
Vol 14 (2) ◽  
pp. 146-152
Author(s):  
Neha Sharma ◽  
Sanjayay Kumar
Keyword(s):  
Zno Nanoparticles ◽  
Spherical Shape ◽  
Xrd Analysis ◽  
Crystalline Size ◽  
X Ray Diffraction ◽  
X Ray ◽  
In Doping ◽  
Vis Spectroscopy ◽  
Doped Zno

In present study, undoped ZnO, Zn0.8Ag0.2O, Zn0.8Al0.2O and Zn0.6Al0.2Ag0.2O samples are synthesized by simple solution method. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX) and UV-visible (UV-Vis) spectroscopy are used to perform the characterization of undoped, doped and codoped samples. XRD analysis is exposed that hexagonal wurtzite crystalline structure obtained for undoped, doped and codoped samples without any extra representation of impurity phases. The crystalline size is when evaluated by using Scherrer, It has 44, 49, 41and 37nm for undoped ZnO, Zn0.8Ag0.2O, Zn0.8Al0.2O and Zn0.6Al0.2Ag0.2O samples. Similarly, the crystalline size and strain are also evaluated by Williamson hall (W-H) and size strain plot (SSP) for the undoped, doped and codoped nanoparticles. The evaluated crystalline size by SSP is three times greater than the result of the scherrer method. The SEM exposes that surface morphology of nanoparticle samples, in this case is the formation of large agglomeration in spherical shape with nanocrystallites of undoped and doped ZnO with apparent and definite boundaries. EDX points out the replacement of Al2+ and Ag+ with Zn2+ in ZnO matrix and consequences in the development of single-phase Zn1−x−yAgxAlyO. The blueshift is shown in UV-Vis absorption spectra because the band gap value increases with the increase in doping, except Ag+ doped ZnO nanoparticles.

Preparation and Adsorbability for Orange II of CTAB Modified Bentonite

2013 ◽  
Vol 807-809 ◽  
pp. 530-533 ◽  
Author(s):  
Guang Hua Wang ◽  
Dong Wan ◽  
Wen Bing Li ◽  
Kun Chen
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
Langmuir Equation ◽  
Orange Ii ◽  
X Ray Diffraction ◽  
Exchange Method ◽  
Modified Bentonite ◽  
X Ray ◽  
Ion Exchange Method ◽  
Scanning Electron ◽  
Good Agreement

Surfactant modified bentonite was prepared using cetyltrimethylammonium bromide (CTAB) by a simple ion exchange method, and the organification of bentonite was proved by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron micrographic (SEM). The adsorption of Orange II(OII) dye onto CTAB modified bentonite was carried out. Compared with natural bentonite, the adsorption capacity of CTAB-Bent for OII was greatly enhanced. The adsorption isotherm of OII was in good agreement with the Langmuir equation.

scholarly journals Magnetic, Structural and Spectroscopic Properties of Iron(II)-Octacyanoniobate(IV) Crystalline Film Obtained by Ion-Exchange Synthesis

Materials ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 3029
Author(s):  
Wojciech Sas ◽  
Dawid Pinkowicz ◽  
Marcin Perzanowski ◽  
Magdalena Fitta
Keyword(s):  
Thin Film ◽  
Ion Exchange ◽  
Coercive Field ◽  
Magnetic Measurements ◽  
Film Formation ◽  
Spectroscopic Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy ◽  
First Time

Over recent years, investigations of coordination polymer thin films have been initiated due to their unique properties, which are expected to be strongly enhanced in the thin film form. In this work, a crystalline [FeII(H2O)2]2[NbIV(CN)8]∙4H2O (1) film on a transparent Nafion membrane was obtained, for the first time, via ion-exchange synthesis. The proper film formation and its composition was confirmed with the use of energy dispersive X-ray spectroscopy and infrared spectroscopy, as well as in situ Ultraviolet-Visible (UV-Vis) spectroscopy. The obtained film were also characterized by scanning electron microscopy, X-ray diffraction, and magnetic measurements. The [FeII(H2O)2]2[NbIV(CN)8]∙4H2O film shows a sharp phase transition to a long-range magnetically ordered state at Tc = 40 K. The 1 film is a soft ferromagnet with the coercive field Hc = 1.2 kOe. Compared to the bulk counterpart, a decrease in critical temperature and a significant increase in the coercive field were observed in the films indicating a distinct size effect. The decrease in Tc could also have been related to the possible partial oxidation of FeII ions to FeIII, which could be efficient, due to the large surface of the thin film sample.

scholarly journals Preparation of CuHY catalyst via solid-state ion exchange method and its catalytic performance in isobutane/2-butene alkylation

RSC Advances ◽  
2021 ◽  
Vol 11 (37) ◽  
pp. 23045-23054
Author(s):  
Xinyan Sun ◽  
Xiang Zhang ◽  
Tao Zheng ◽  
Haiyan Liu ◽  
Rui Zhang ◽  
...  
Keyword(s):  
Solid State ◽  
Ion Exchange ◽  
Catalytic Performance ◽  
Exchange Method ◽  
Hy Zeolite ◽  
Ion Exchange Method

CuHY prepared by solid-state ion exchange of HY zeolite with CuCl was used as a catalyst in isobutane/2-butene alkylation. The selectivity of C8 and trimethylpentanes over CuHY in alkylate are improved compared with those of HY.

scholarly journals Comparative study of layered tetravalent metal phosphates containing various first-row divalent metals. Synthesis, crystalline structure

2007 ◽  
Vol 5 (2) ◽  
pp. 516-535 ◽  
Author(s):  
László Szirtes ◽  
László Riess ◽  
János Megyeri ◽  
Ernõ Kuzmann
Keyword(s):  
Ion Exchange ◽  
Transition Metal ◽  
Transition Metals ◽  
Comparative Study ◽  
Powder Diffraction ◽  
Layered Structure ◽  
Exchange Method ◽  
X Ray ◽  
Metal Phosphates ◽  
Ion Exchange Method

AbstractThe transition metal forms of α-zirconium-. titanium-, and hafnium phosphates were prepared by ion exchange method. Their structure was investigated by X-ray powder diffraction (XRPD) method. It was found that the transition metal containing phosphates have the same layered structure as the pristine tetravalent metal phosphates, except for the increase of interlayer distance from 7.6 Å to ∼9.5 Å. As a result of the incorporation of transition metals in the layers, the c-axis is increased from ∼15 Å to ∼20 Å (in the case of titanium phosphate to ∼25 Å). All other parameters (a, b and β °) are practically unchanged.

scholarly journals Preparation and Characterization of Cetyl Trimethylammonium Intercalated Sericite

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Hao Ding ◽  
Yuebo Wang ◽  
Yu Liang ◽  
Faxiang Qin
Keyword(s):  
Ion Exchange ◽  
Interlayer Space ◽  
Xrd Analysis ◽  
Acid Activation ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Intercalated sericite was prepared by intercalation of cetyl trimethylammonium bromide (CTAB) into activated sericite through ion exchange with the following two steps: the activation of sericite by thermal modification, acid activation and sodium modification; the ion exchange intercalation of CTA+into activated sericite. Effects of reaction time, reaction temperature, CTAB quantity, kinds of medium, and aqueous pH on the intercalation of activated sericite were examined by X-ray diffraction (XRD) analysis, Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The results indicated that the CTA+entered sericite interlayers and anchored in the aluminosilicate interlayers through strong electrostatic attraction. The arrangement of CTA+in sericite interlayers was that alkyl chain of CTA+mainly tilted at an angle about 60° (paraffin-type bilayer) and 38° (paraffin-type monolayer) with aluminosilicate layers. The largest interlayer space was enlarged from 0.9 nm to 5.2 nm. The intercalated sericite could be used as an excellent layer silicate to prepare clay-polymer nanocomposites.

Structural Reinvestigation of Alkali Hexatitanate

2011 ◽  
Vol 170 ◽  
pp. 208-212
Author(s):  
Kunimitsu Kataoka ◽  
Norihito Kijima ◽  
Hiroshi Hayakawa ◽  
Junji Akimoto
Keyword(s):  
Ion Exchange ◽  
Single Crystal ◽  
Molten Salt ◽  
Type Structure ◽  
Exchange Method ◽  
Space Group ◽  
X Ray ◽  
Structure Space ◽  
Li Ion ◽  
Ion Exchange Method

Na1.614Li0.386Ti6O13 Single crystal was synthesized by a Li+ ion-exchange method from Na2Ti6O13 single crystal in a molten salt of LiNO3. The obtained Na1.614Li0.386Ti6O13 single-crystal is colorless and has the shape of a rod. Na1.614Li0.386Ti6O13 crystallizes in the monoclinic tunnel type structure, space group C2/m, and lattice parameters a = 15.144(2) Å, b = 3.7492(5) Å, c = 9.162(2) Å and β = 99.0131(9)º. The structure was determined by a single-crystal X-ray study and refined to the conventional values of R = 0.0247 and wR = 0.0451 for 969 independent observed reflections.

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