Research Article Preparation and Characterization of ...of cubic -Fe 2 O 3 (hematite) microparticles...

Hindawi Publishing CorporationJournal of ChemistryVolume 2013 Article ID 412308 10 pageshttpdxdoiorg1011552013412308

Research ArticlePreparation and Characterization of Promoted Fe-VSiO2Nanocatalysts for Oxidation of Alcohols

Hamid Reza Rafiee1 Mostafa Feyzi12 Fatanh Jafari1 and Banafsheh Safari1

1 Faculty of Chemistry Razi University PO Box +98-67149 Kermanshah Iran2Nanoscience amp Nanotechnology Research Center (NNRC) Razi University PO Box +98-67149 Kermanshah Iran

Correspondence should be addressed to Mostafa Feyzi dalahoo2011yahoocom

Received 27 May 2013 Accepted 20 August 2013

Academic Editor Giuseppe Gattuso

Copyright copy 2013 Hamid Reza Rafiee et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

A series of SiO2supported iron-vanadium catalysts were prepared using sol-gel and wetness impregnation methods This research

investigates the effects of V and Cu on the structure and morphology of FeSiO2catalysts The SiO

2supported catalyst with

the highest specific surface area and pore volume was obtained when it is containing 40wt Fe 15 wt V and 2wt CuCharacterization of prepared catalysts was carried out by powder X-ray diffraction (XRD) scanning electron microcopy (SEM)vibrating sample magnetometry (VSM) Fourier transform infrared (FT-IR) spectrometry temperature program reduction (TPR)N2physisorption and thermal analysis methods such as thermal gravimetric analysis (TGA) and differential scanning calorimetry

(DSC) The Fe-VSiO2catalyst promoted with 2wt of Cu exhibited typical ferromagnetic behavior at room temperature with

a saturation magnetization value of 1144 emug This character of catalyst indicated great potential for application in magneticseparation technologies The prepared catalyst was found to act as an efficient recoverable nanocatalyst for oxidation reaction ofalcohols to aldehydes and ketones in aqueous media under mild condition Moreover the catalyst was reused five times withoutsignificant degradation in catalytic activity and performance

1 Introduction

The synthesis of nanostructured magnetic materials hasbecome a particularly important area of research and isattracting a growing interest due to their chemical and phys-ical properties which differ significantly from bulk materialThis leads to a broad range of applications such as hyperther-mia [1] information storage media [2] magnetic resonanceimaging (MRI) [3 4] drug delivery and bioadsorption [5]and catalytic applications [6ndash8] Magnetic nanoparticles havebeen synthesized with a number of different compositionsand phases including puremetals Fe Co andNi [9ndash11]metaloxides Fe

3O4and 120574-Fe

2O3[12 13] ferrites such as Co

1minusxZnxFe2O4 [14] metal alloys as FeCu [15] and supportedsolid catalyst such as iron oxide nanoparticles in a silicamatrix [16]The use ofmagnetic nanoparticles as the catalystshas been attracting great attention as a useful strategy forimproving the catalytic efficiency of heterogeneous catalystsin a wide range of synthetic transformations Nanometermagnetic solid base catalyst can be separated easily from

the reagents by applying an externalmagnetic field which caneffectively prevent catalyst loss and improve its recovery rateduring separation process and can increase the durability ofthe catalyst Furthermore magnetic nanoparticles-supportedsolid catalyst shows high dispersion to contact reactantsmore sufficiently based on the high surface area of the sup-ported magnetic nanoparticles [17] In particular magneticnanosized transition metal oxides are considered as promis-ing catalysts of various reactions particularly oxidation oforganic substrates [18] Varying the fabrication conditionsof such oxides is the main method used to control theirphase composition size or surface and thus their propertieswhich strongly depends on the above mentioned structuralfeatures In fact the catalytic and other properties depend onthe morphology particle size and surface area Moreoverthe preparation method plays a key role in determining theparticle size and shape size distribution surface chemistryand therefore the applications of the material Preparationof the magnetic nanoparticles requires several tasks such ascontrol of the size and size distribution of the particles

2 Journal of Chemistry

control of the morphology and crystallinity and preven-tion of the agglomeration Different preparation methodshave been developed in order to obtain desirable samplesand physical properties thermal decomposition ultrasonicspray pyrolysis (USP) chemical vapor deposition and sono-chemical technique [19ndash22] Yin et al reported synthesisof cubic 120572-Fe

2O3(hematite) microparticles via a simple

one-step hydrothermal reaction [23] Iron and iron oxidenanoparticles in silica layers were deposited by sol-gel tech-niques prepared by Simkien et al [24] It was shown thatmultifunctional nanoparticles of different iron oxides pos-sessing various physical properties can be fabricated bymeans of postgrowth annealing of (SiO

2 Fe)SiO

2Si samples

in various atmospheres The hematite maghemite and ironnanoparticles were found to be dominant upon annealing thesamples in air argon and hydrogen atmosphere respectivelyThe synthesis of monodispersed 120574-Fe

2O3nanoparticles by

mechanochemical processing indicated that the nanoparti-cles had a volume-weighted mean diameter of 6 nm and anarrow size distribution with the standard deviation of 3 nm[25] Orolınova et al [26] reported that synthesis of magneticclay composite prepared by the method of precipitation ofiron oxide onto the clay surface was subjected to a heattreatment The sol-gel method has been shown to be veryuseful for preparation of iron oxide nanoparticles dispersedin an amorphous silica matrix Silica is convenient becauseof its nontoxic nature high biocompatibility prevention ofagglomeration temperature resistance chemical inertnessand adjustable pore diameter [27 28]The aim of this study isthe synthesis of magnetic Fe-VSiO

2nanocatalysts promoted

by copper via sol-gel and impregnationmethod for oxidationof organic compounds Characterization of catalysts wascarried out using XRD SEM TPR TGA DSC and N

2

adsorption-desorption measurements We also report themagnetic properties measured by a vibrating sample magne-tometer (VSM)

2 Experimental

21 Synthesis of FeSiO2Nanocatalyst All materials with ana-

lytical purity were purchased from Merck and used withoutfurther purificationThe supported iron catalysts with differ-ent amount of Fe (40 50 60 70 and 80wt) were preparedusing sol-gelmethod Ironnitrate Fe(NO

3)3sdot9H2O tetraetho-

xysilane TEOS and oxalic acid H2C2O4sdot2H2O appropriate

amounts for TEOS hydrolysis are separately dissolved in eth-anol The three solutions were heated up to 50∘C and stirredfor 20min The TEOS was added to the iron nitrate and sub-sequently oxalic acid added to the previous mixture understrong stirring at 60∘C for 2 h The precipitate composed ofiron oxalate and TEOS was progressively hydrolyzed by thehydrationwater of ironnitrate andmainly oxalic acid accord-ing to the following scheme

Si(OC2H5)4+ 4H2O 997888rarr Si(OH)

4+ 4C2H5OH (1)

In the acidic condition (pH asymp 1) Si(OH)4condensed with

other materials to homogeneous gel The monolithic gel wasdried at 110∘C in vacuum for 16 h At last the dried powderwas calcined (450∘C for 6 h) to produce solid magneticcomposite catalyst

22 Synthesis of Fe-VSiO2Catalyst TheFe

2O3SiO2was syn-

thesized in Section 21 and then was impregnated with anaqueous solution containingNH

4VO3(1M) by adding differ-

ent wt of V (119909 = 5ndash20) and results show that 119909 = 15wt isan optimal wt The catalyst containing 40wt Fe-15 wtV was impregnated with 1ndash5wt of CuThe optimal catalystcontaining 40wt Fe-15 wt VSiO

2was promoted with 1ndash

5wt of Cu Then the optimal sample containing 40wtFe-15 wt VSiO

2was promoted with 2wt of Cu dried at

110∘C for 12 h and calcined at different calcination conditions(Figure 1)

23 Catalyst Characterization

231 X-Ray Diffraction (XRD) The XRD patterns of all theprecursor and calcined samples were recorded on a PhilipsXrsquo Pert (40 kV 30mA) X-ray diffractometer using a Cu K120572radiation source (120582 = 1542 A) and a nickel filter in the 2120579range of 4∘ndash70∘

232 N2-Adsorption-Desorption Measurements The specific

surface area (using BET and BJH methods) the total porevolume and themean pore diameter weremeasured using anN2adsorption-desorption isotherm at liquid nitrogen tem-

perature (minus196∘C) using a NOVA 2200 instrument (Quan-tachrome USA) Prior to the adsorption-desorption mea-surements all the samples were degassed at 110∘C in an N

2

flow for 3 h to remove the moisture and other adsorbates

233 Thermal Gravimetric Analysis (TGA) and DifferentialScanning Calorimetry (DSC) The TGA and DSC were car-ried out using simultaneous thermal analyzer (Perkin Elmer)under a flow of dry air with a flow rate of 50mLminminus1 Thetemperature was raised from 20 to 600∘C using a linear pro-grammer at a heating rate of 3∘Cminminus1

234 Scanning Electron Microscopy (SEM) The morpholo-gies of prepared nanocatalysts and their precursors wereobserved bymeans of an S-360Oxford Eng scanning electronmicroscope (USA)

235 Temperature-Programmed Reduction (TPR) TPR pro-files of the Fe

2O3SiO2nanocatalysts were recorded using a

micromeritic TPD-TPR 290 systemTheTPR for each sample(50mg) was performed using a mixture gas of 5 H

295

Ar (vv) as the reductant The sample was heated from 25 to900∘C at a heating rate of 5∘Cmin The flow rate of the mix-ture gas was 50mLminminus1

236 Fourier Transform Infrared (FTIR) Spectrometry TheFT-IR spectra were recorded with a VERTEX 70 (BrukerGermany) FT-IR spectrophotometer equipped with a deu-terium triglycine sulfate (DTGS) detector Samples of 1-2mgwere mixed with 100mg KBr and pressed into translucentdisks at room temperature

Journal of Chemistry 3

Mixing

Aging

Drying

Calcination

FeSiO2nanocatalyst

Sequentiallyimpregnation of V and Cu

Gelformation

H2C2O4middot2H2OEtOH + TEOS

nanocatalystFe-VSiO2

Fe(NO3)3middot9H2O + EtOH

Figure 1 Diagram of the chemical process for the preparation of Fe-VSiO2nanocatalyst

All spectra were taken in the range 4000ndash400 cmminus1 at aresolution of 4 cmminus1 The spectra of all samples were pre-sented by subtracting the background spectrum

237 Vibrating Sample Magnetometer (VSM) The magneticmeasurements of final catalyst were carried out in a vibratingsample magnetometer (VSM BHV-55 Riken Japan) at roomtemperature

3 Results and Discussion

31 Effect of Loading of Fe One of themost important factorswhich have influences on the magnetic properties specificsurface area and morphology of the catalyst is the loadingof Fe To understand this a series of FeSiO

2catalysts having

different weight of Fe (40 50 60 70 and 80) were preparedat calcination conditions 119879 = 450∘C 6 h and heating rateof 3∘Cminminus1 The preparation conditions are effective onporosity and surface area of FeSiO

2catalyst To indicate this

the N2absorption-desorption isotherms of catalyst samples

were taken for evaluating the specific surface area porevolume and pore size distribution Figure 2 represents thesecharacters for FeSiO

2catalysts that were prepared with

different wt of FeThe obtained results in Figure 2 show that the Fe loading

can be affected on the specific surface area pore volumeand pore size distribution of all catalysts Furthermore it

is apparent that amount of Fe significantly influences theincreasing of the surface area pore volume and pore size dis-tribution of catalysts It is probably due to increasing amountof SiO

2which facilitates the high dispersion of the catalyst

crystallites The specific surface area pore volume and porediameter results for the calcined catalysts containing differentwt of Fe have shown that the specific surface area valueand pore volume for the calcined catalyst containing 40wtof Fe are relatively higher than those of the other calcinedsamplesTheN

2absorption-desorption data have shown that

the catalyst containing 60wtof Fe has higher pore diameterthan the other calcined catalysts So the optimum value foriron loading is 40wt percent Characterization studies werecarried out using XRD technique for the FeSiO

2catalyst

(Figure 3) The actual identified phases for this catalyst wereFe2SiO4(cubic) and Fe

2O3(rhombohedral) H

2-TPR profiles

of Fe-VSiO2nanocatalyst are depicted in Figure 6 The

reduction process of the FeSiO2nanocatalyst occurs in two

distinct stagesThefirst stage (around 415∘C) is ascribed to thetransformations of Fe

2O3rarr Fe3O4whereas the second stage

(around 530∘C) represents the transformation of Fe3O4rarr

Fe [29] H2consumed during different reduction stages was

determined by integrating the area of TPR curvesThe resultshave shown that the H

2adsorption for this catalyst is 94 times

10minus2mmol H2per mmol of catalyst

Furthermore the crystallite sizes of the calcined samplecontaining 40wt of Fe were calculated from the major


180182184186188190192194196198200

40 50 60 70 80Fe (wt)

Spec

ific s

urfa

ce ar

ea (m

2gminus

1)

(a)

40 50 60 70 800054

0056

0058

006

0062

0064

0066

0068

Pore

dia

met

er (A

)

Fe (wt)

(b)

40 50 60 70 80

15

16

148

152

154

156

158

162

Fe (wt)

Pore

vol

ume (

cm3

gminus1)

(c)

Figure 2 N2adsorption-desorption measurements of FeSiO

2catalysts with different wt of Fe

20

10

0

20 30 40 50 60

2120579

Fe2SiO4

Fe2O3

Figure 3 XRD patterns of the FeSiO2nanocatalyst

diffraction peaks in XRD pattern using the Debye-Scherrerequation [30] The particle size of the calcined catalyst con-taining 40wt of Fe was calculated from the most intenseline (2120579 = 36∘) and it is about 55 nm It is clear that the cat-alyst particle size was in nanodimension (55 nm) The sam-ple containing 40wt of Fe was characterized with SEM(Figure 4(b)) It is obvious in this figure that the crystal sizeswere from 42 to 60 nm This result confirmed the obtainedresults studied using the Scherrer equation

The XRD technique may not be sufficiently sensitiveto reveal the fine details of these changes To get this adetailed SEM study of both precursor and calcined FeSiO

2

nanocatalyst was done and the results are given in Figure 4SEM observations have shown differences in morphology ofprecursor and calcined catalysts The image obtained fromcatalyst precursor depicts several larger agglomerations ofparticles (Figure 4(a)) and shows that this material has a lessdense and homogeneousmorphology After the calcination at450∘C for 6 hours and heating rate of 3∘Cminminus1 themorpho-logical features were different with the precursor samples andshow that the agglomerate size is greatly reduced compared tothe precursor (Figure 4(b)) Itmay be assigned to the coveringof calcined catalyst surface by small crystallite of iron oxidesin agreement with XRD results The TGA curve for FeSiO

2

catalyst precursor is shown in Figure 5 The weight lossesfound from TGA measurements agree fairly well with thoseexpected for the decomposition of hydroxyl or oxalate phasesto oxides For this catalyst precursor the thermogravimetriccurve seems to indicate three-stage decompositionThe first-stage is considered to be due to the removal of adsorbedwater and ethanol (25ndash195∘C) while the second stage comesfrom the decomposition of hydroxyl phases (230ndash370∘C)respectively The third stage around 390ndash420∘C is the resultof the full decomposition of hydroxyl and oxalate phasesto oxides The TGA curve is involved with a total overallweight loss of ca 40wt DSCmeasurement was performedin order to provide further evidence for the presence of thevarious species and evaluate their thermal behavior As it isshown in Figure 5 the exothermic peak at lower temperature


5 120583m

(a)

1 120583m

(b)

Figure 4 The SEM images of FeSiO2nanocatalyst (a) precursor and (b) calcined catalyst

90

70

50

30

10

00 200 400 600

18

16

14

12

10

8

Hea

t flow

(mca

ls)

Wt l

oss (

)

Wei

ght (

mg)

Temperature (∘C)

Figure 5 TGA and DSC curves for FeSiO2precursor

530∘C

415∘C

0 100 300 500 700 900

Temperature (∘C)

H2

cons

umpt

ion

(au

)

Figure 6 TPR profile of FeSiO2nanocatalyst

represents the removal of the physically adsorbed water andethanol from the material The endothermic peaks around230ndash370∘C and 280ndash530∘C are due to the decomposition ofhydroxyl and phases respectively

32 Effect of Heating Rate in Calcinations on the SurfaceProperties In order to study the effect of calcination heatingrate on the catalyst property a series of catalyst precursorscontaining 40 FeSiO

2were calcined (at 450∘C for 6 h) at

various heating rates in air atmosphere The specific surfacearea results (BET BJH and DH methods) pore volumesand pore diameters of the calcined catalysts are given inTable 1 According to the obtained results the specific surfaceareas are dependent on the heating rate When heatingrate increases from 2∘Cmin to 4∘Cmin the average porediameter increases a bit and the surface area decreased from1885 to 1826m2 gminus1 This may be due to the fact that agreat deal of heat cannot be emitted within a short periodof time which induces the agglomeration of nanoparticles[31] The BET specific surface area results for the calcinedcatalysts at different heating rates have shown that thespecific surface area values obtained for the calcined catalystin calcination rate 2∘Cmin (1885 1922 and 1935m2 gminus1measured by different methods) are relatively higher thanthose observed for those calcined catalysts in 3 and 4∘CminPrevious researchers had reported that the activity of thecatalyst is depending on BET surface area pore diameterand pore volume [32 33] Jacobson et al [34] reported thatpore structure is a primary requirement for an ideal solidcatalyst for biodiesel production since a typical triglyceridemolecule has a pore diameter of approximately 58 A Thelarger average pore diameter and larger interconnected poreswould minimize diffusion limitations of reactant moleculesConsequently the reactants easily diffused into the interiorof the catalyst became in contact with more acid-basic activesites and lead to better catalytic activity Besides all the cata-lysts could be defined as mesoporous catalysts since the porediameter of each catalyst was in intermediate range between2 nm (micropore) and 50 nm (macropore) The mesoporouscatalyst has been widely used in transesterification reactionin previous studies [35ndash37] In addition the specific porevolume which represents the total internal volume per unitmass of catalyst would facilitate the reaction by amplifyingthe reaction surface


Table 1 N2 adsorption-desorption measurements of FeSiO2 nanocatalysts at different calcination heating rates

Heatingrate (∘Cminminus1)

Specific surface area (m2 gminus1) Pore diameter (A) Pore volume (cm3 gminus1)BET BJH DH BJH DH BJH DH

2 1885 1922 1935 744 747 165 16493 1857 187 1892 720 728 1694 16984 1826 1831 1842 710 720 1681 1689

158

160

162

164

166

168

170

172

174

0 5 10 15 20

V (wt)

Spec

ific s

urfa

ce ar

ea (m

2gminus

1)

(a)

0 5 10 15 20

0052

0054

0056

0058

006

0062

0064

0066

0068

007

0072

Pore

dia

met

er (A

)V (wt)

(b)

0 5 10 15 20

14

145

15

155

16

165

17

175

V (wt)

Pore

vol

ume (

cm3

gminus1)

(c)

Figure 7 N2adsorption-desorption measurements of Fe-VSiO

2nanocatalysts at different V loading

33 Effect of Loading of Vanadium on the Surface PropertiesFigure 7 represents the results of surface factors for 40wtFe-119909VSiO

2nanocatalysts which impregnated with different

weight percents of V (119909 = 5 10 15 and 20wt of V based onthe SiO

2weight) The obtained results in Figure 7 show that

theV loading can be by affected the surface properties of cata-lyst As can be seen at first amount ofV significantly increasesthe surface area pore volume and pore size distribution of Fe-VSiO

2nanocatalysts and then they decreased It can be seen

that the calcined catalyst containing 15wt of V has higherspecific surface area than the other prepared catalysts On theother hand as it can be seen from Figure 7 with the increasein wt of V the specific surface area increased at first andthen decreased when 15wt of V loaded which is due to theblockage of the micropores of SiO

2 This occurs because the

impregnation of the support with metal clogs the pores of theSiO2[39 40]

34 Effect of Loading of Cu Theeffect of wt of Cuwas stud-ied (1 2 3 4 and 5wt based on the total Fe and V weight)on the catalyst properties of the Fe-VSiO

2catalystThe effect

of adding copper to the 40wt Fe-15 wtVSiO2catalysts is

mainly an increase in the rate of reduction of iron leading toa larger number of active sites [41]The additives are effectiveon porosity and surface area of catalyst To evaluate thisthe N

2absorption-desorption isotherms of catalyst samples

were analyzed for specific surface area measurements porevolume and pore size distribution The pore structure andthe specific surface area of catalysts were obtained using BJHDH and BET methods and the results are shown in Table 2It can be clearly seen that the addition of different amountsof copper increases the BET surface area of the catalysts butfurther increase inCu results in a decrease in surface areaTheresults may be ascribed to the improved dispersion of ironand vanadium oxides at low Cu loading [42] However


Table 2 Textural properties of the catalysts with different copper contents

Wt Cu Specific surface area (m2 gminus1) Pore diameter (A) Pore volume (cm3 gminus1)BET BJH DH BJH DH BJH DH

0 1732 1744 1771 705 712 1748 17612 1796 1785 1813 707 711 1675 16833 1734 1731 1759 624 627 1603 15985 1704 1713 1706 602 608 1596 1582

400

300

200

100

020 30 40 50 60

Fe2O3

Fe3O4

SiO2

2120579 (∘)

Figure 8 XRD patterns of the Fe-VSiO2promoted with copper

nanocatalyst

the promotional effect on dispersion is possibly offset byanother factor which is the blockage of mesoporous of cat-alyst by further Cu loading This postulated explanation canbe evidenced by the pore size distribution of the catalysts

The increment in surface area might be due to the stronginteraction of the Cu with SiO

2support which reduced the

surface diffusion of Fe inhibited sintering and stabilized thecrystal surface of SiO

2 Characterization studies were carried

out using XRD technique for the final calcined Fe-VSiO2

nanocatalysts Figure 8 shows the XRDpattern of the 40wtFe-15 wt VSiO

2catalyst that was promoted with 2wt of

Cu as optimal catalyst The actual identified phases for thiscatalyst were Fe

2O3(rhombohedral) Fe

3O4(cubic) and SiO

2

(tetragonal) From the XRD data the crystallite size of theprepared nanocatalyst was calculated to be 46 nm

The FT-IR spectrum of catalyst is shown in Figure 9Broad peak at 3447 cmminus1 could be correlated to the vibrationof structural OH [43] The bands at 1083 800 and 452 cmminus1are attributed to the asymmetric SindashOndashSi stretching vibrationthe symmetric SindashOndashSi stretching vibration and the OndashSindashOshearing vibration [44 45]Thebands around 1000 cmminus1 wereassigned to the asymmetric FendashOndashSi stretching vibration [4446 47] These results suggested that the FendashSiO

2interaction

exists in the catalyst in a form of FendashOndashSi structureThe bandat 551 cmminus1 can be assigned to the FendashO stretching in FendashOndashSibonds [43]

The magnetic properties of the nanoparticles were char-acterized using a vibrating samplemagnetometer (VSM)Theroom temperature magnetization curve of the final catalyst is

0

005

01

015

02

025

03

035

04

045

0 1000 2000 3000 4000 5000Tr

ansm

ittan

ceWave number

Figure 9 FT-IR spectrum of the Fe-VSiO2promoted with copper

nanocatalyst

shown in Figure 10 The sample exhibited typical ferromag-netic behavior at room temperature The observed value ofsaturation magnetization of the sample was 1144 emug

35 Catalytic Performance of Optimal Catalyst The synthe-sized optimal nanocatalyst (40wt Fe-15 wt VSiO

2cat-

alyst that was promoted with 2wt of Cu) was employedfor oxidation reaction of alcohols to aldehydes and ketonesWe carry out these reactions under atmospheric oxygen(Scheme 1)

The progress of reactions was monitored by TLC Table 3gives the oxidation results Compared to what Velusamy et alreported [48] our catalyst has a better performance for thementioned reactions The observed shorter reaction timescompared to their catalyst (eg forecasted time is 22ndash25 hourand reaction time is 20 hour) can be interpreted by con-sidering the fact that Fe-VSiO

2nanocatalyst has a higher

surface area compared to their catalyst Also after completionof the reactions recovery of Fe-VSiO

2nanocrystals from the

reaction mixture was easily achieved by applying an externalpermanent magnet on the outside wall of the reaction tubeas shown in Figure 11Therefore the products were isolated ingood purity after the volatile portions were removed and theproduct was purified All isolated products gave satisfactoryspectral data (1HNMR) compared with those reported in theliterature [48] At the end of the reaction to determine theapplicability of catalyst recovery we decanted the vessel by theuse of an external magnet and remained catalyst was washedwith diethyl ether to remove residual product and then driedunder vacuum


Table 3 Catalyzed oxidation reactions

Entry Substrate Product Time(h)

MP (∘C)found

MP (∘C) reported[38]

1

CH2OH CHO

12 Oil minus26

2

CH2OH

MeO

CHO

MeO

18 Oil 0

3

CH2OH

O2N

CHO

O2N20 104 105

4OH

CHO

11 Oil minus75

5

OH O

8 19 20

6

OH O

13 48 48

minus15

minus10

minus5

0

5

10

15

minus10000 minus5000 0 5000 10000

Applied field (Oe)

Mag

netiz

atio

n (e

mu

g)

Figure 10 Hysteresis loop for Fe-VSiO2nanocrystals at room

temperature

4 Conclusions

Thepreparation and characterization of Fe-VSiO2nanocrys-

tals were described in this work Synthesizedmaterial acts as apowerful and heterogeneous catalyst for oxidation reactionsTherefore can utilize in mild reaction conditions shorterreaction times product purity and therefore cost efficiencyare of advantages of this nanocatalyst Besides that the newcatalyst can be effectively reused With regard to observedsatisfactory catalytic properties it is expected that it can be agood potentially substitute for some commercial catalysts

SubstratesMagnetCatalyst

Figure 11 Magnetic properties of optimal nanocatalyst can lead toits separation from the reaction medium

OH

OH H

R R

RR

R998400 R998400O2 (1 atm)

5 mol nanocatalyst

O2 (1 atm)5 mol nanocatalyst

O

O

C

C R Ar alkyl

R R998400 Ar alkyl

05 eq K2CO3

toluene 100∘C

toluene 100∘C

Scheme 1 Fe-VSiO2catalyzed oxidation reactions


References

[1] J-P Fortin CWilhelm J Servais CMenager J-C Bacri and FGazeau ldquoSize-sorted anionic iron oxide nanomagnets as colloi-dal mediators for magnetic hyperthermiardquo Journal of the Amer-ican Chemical Society vol 129 no 9 pp 2628ndash2635 2007

[2] Z Jing YWang and SWu ldquoPreparation and gas sensing prop-erties of pure and doped 120574-Fe

2O3by an anhydrous solvent

methodrdquo Sensors and Actuators vol 113 no 1 pp 177ndash181 2006[3] M C Bautista O Bomati-Miguel X Zhao et al ldquoComparative

study of ferrofluids based on dextran-coated iron oxide andmetal nanoparticles for contrast agents in magnetic resonanceimagingrdquo Nanotechnology vol 15 no 4 pp S154ndashS159 2004

[4] N Kohler C Sun A Fichtenholtz J Gunn C Fang and MZhang ldquoMethotrexate-immobilized poly(ethylene glycol) mag-netic nanoparticles for MR imaging and drug deliveryrdquo Smallvol 2 no 6 pp 785ndash792 2006

[5] S Huang C Li Z Cheng et al ldquoMagnetic Fe3O4mesoporous

silica composites for drug delivery and bioadsorptionrdquo Journalof Colloid and Interface Science vol 376 no 1 pp 312ndash321 2012

[6] B V S Reddy A S Krishna A V Ganesh and G G K S NKumar ldquoNano Fe

3O4as magnetically recyclable catalyst for the

synthesis of 120572-aminophosphonates in solvent-free conditionsrdquoTetrahedron Letters vol 52 no 12 pp 1359ndash1362 2011

[7] M Masteri-Farahani and Z Kashef ldquoSynthesis and characteri-zation of new magnetically recoverable molybdenum nanocat-alyst for epoxidation of olefinsrdquo Journal of Magnetism andMag-netic Materials vol 324 no 7 pp 1431ndash1434 2012

[8] S Rostamizadeh M Azad N Shadjou and M Hasanzadehldquo(Alpha-Fe

2O3)-MCM-41-SO

3H as a novel magnetic nanocat-

alyst for the synthesis of N-aryl-2-amino-1 6-naphthyridinederivativesrdquo Catalysis Communications vol 25 pp 83ndash91 2012

[9] S-J Park S Kim S Lee Z G Khim K Char and T HyeonldquoSynthesis and magnetic studies of uniform iron nanorods andnanospheresrdquo Journal of theAmericanChemical Society vol 122no 35 pp 8581ndash8582 2000

[10] V F Puntes K M Krishnan and A P Alivisatos ldquoColloidalnanocrystal shape and size control the case of cobaltrdquo Sciencevol 291 no 5511 pp 2115ndash2117 2001

[11] X Sun A GutierrezM J Yacaman X Dong and S Jin ldquoInves-tigations on magnetic properties and structure for carbonencapsulated nanoparticles of Fe Co NirdquoMaterials Science andEngineering A vol 286 no 1 pp 157ndash160 2000

[12] M M Mojtahedi M S Abaee A Rajabi P Mahmoodi and SBagherpoor ldquoRecyclable superparamagnetic Fe

3O4nanoparti-

cles for efficient catalysis of thiolysis of epoxidesrdquo Journal ofMolecular Catalysis A vol 361-362 pp 68ndash71 2012

[13] M S Islam J Kurawaki Y Kusumoto M Abdulla-Al-Mamunand M Z Bin Mukhlish ldquoHydrothermal novel synthesisof neck-structured hyperthermia-suitable magnetic (Fe

3O4

gamma-Fe2O3and alpha-Fe

2O3) nanoparticlesrdquo Journal of

Scientific Research vol 4 pp 99ndash107 2012[14] I Sharifi and H Shokrollahi ldquoNanostructural magnetic and

Mossbauer studies of nanosizedCo1minus119909

Zn119909Fe2O4synthesized by

co-precipitationrdquo Journal ofMagnetism andMagneticMaterialsvol 324 pp 2397ndash2403 2012

[15] X Zhang BWang and X Xu ldquoSynthesis andmagnetic proper-ties of Cu-coated Fe composite nanoparticlesrdquo Applied SurfaceScience vol 256 no 13 pp 4109ndash4113 2010

[16] M Tadic V Kusigerski D Markovic M Panjan I Milosevicand V Spasojevic ldquoHighly crystalline superparamagnetic iron

oxide nanoparticles (SPION) in a silicamatrixrdquo Journal of Alloysand Compounds vol 525 pp 28ndash33 2012

[17] S Tang L Wang Y Zhang S Li S Tian and B Wang ldquoStudyon preparation of CaAlFe

3O4magnetic composite solid cat-

alyst and its application in biodiesel transesterificationrdquo FuelProcessing Technology vol 95 pp 84ndash89 2012

[18] S C Tsang V Caps I Paraskevas D Chadwick and DThompsett ldquoMagnetically separable carbon-supported nano-catalysts for the manufacture of fine chemicalsrdquo AngewandteChemie vol 43 no 42 pp 5645ndash5649 2004

[19] F Zhao B Zhang and L Feng ldquoPreparation and magneticproperties of magnetite nanoparticlesrdquo Materials Letters vol68 pp 112ndash114 2012

[20] S Gurmen and B Ebin ldquoProduction and characterization of thenanostructured hollow iron oxide spheres and nanoparticles byaerosol routerdquo Journal of Alloys and Compounds vol 492 no1-2 pp 585ndash589 2010

[21] V de Castro G Benito S Hurst C J Serna M P Morales andS Veintemillas-Verdaguer ldquoOne step production of magneticnanoparticle films by laser pyrolysis inside a chemical vapourdeposition reactorrdquo Thin Solid Films vol 519 no 22 pp 7677ndash7682 2011

[22] MNazrul Islam L van Phong J-R Jeong andC Kim ldquoA facileroute to sonochemical synthesis of magnetic iron oxide (Fe

3O4)

nanoparticlesrdquoThin Solid Films vol 519 no 23 pp 8277ndash82792011

[23] C-Y Yin M Minakshi D E Ralph Z-T Jiang Z Xie and HGuo ldquoHydrothermal synthesis of cubic 120572-Fe

2O3microparticles

using glycine surface characterization reaction mechanismand electrochemical activityrdquo Journal of Alloys and Compoundsvol 509 no 41 pp 9821ndash9825 2011

[24] I Simkien M Treideris G Niaura et al ldquoMultifunctional ironand iron oxide nanoparticles in silicardquoMaterials Chemistry andPhysics vol 130 no 3 pp 1026ndash1032 2011

[25] T Tsuzuki F Schaffel M Muroi and P G McCormickldquoMagnetic properties of mechanochemically synthesized 120574-Fe2O3nanoparticlesrdquo Journal of Alloys and Compounds vol

509 no 17 pp 5420ndash5425 2011[26] Z Orolınova A Mockovciakova V Zelenak and M Myndyk

ldquoInfluence of heat treatment on phase transformation of clay-iron oxide compositerdquo Journal of Alloys and Compounds vol511 no 1 pp 63ndash69 2012

[27] I Ursachi A Vasile A Ianculescu E Vasile and A StanculdquoUltrasonic-assisted synthesis and magnetic studies of ironoxideMCM-41 nanocompositerdquoMaterials Chemistry and Phys-ics vol 130 no 3 pp 1251ndash1259 2011

[28] S Gandhi S Venkatesh U Sharma N R Jagannathan SSethuraman and U M Krishnan ldquoSuperparamagnetic nano-systems based on iron oxide nanoparticles ampmesoporous silicasynthesis amp evaluation of their magnetic relaxometric and bio-compatability propertiesrdquo Journal of Materials Chemistry vol21 no 39 pp 15698ndash15707 2011

[29] H Wang Y Yang J Xu H Wang M Ding and Y Li ldquoStudy ofbimetallic interactions and promoter effects of FeZn FeMn andFeCr Fischer-Tropsch synthesis catalystsrdquo Journal of MolecularCatalysis A vol 326 no 1-2 pp 29ndash40 2010

[30] R Jenkins and R L Sder X-Ray Powder Diffractometry Chem-ical Analysis John Wiley and Sons New York NY USA 1996

[31] Y Wu Y He T Wu T Chen WWeng and HWan ldquoInfluenceof some parameters on the synthesis of nanosized NiOmaterialbymodified sol-gel methodrdquoMaterials Letters vol 61 no 14-15pp 3174ndash3178 2007


[32] WXieH Peng and L Chen ldquoTransesterification of soybean oilcatalyzed by potassium loaded on alumina as a solid-base cata-lystrdquo Applied Catalysis A vol 300 no 1 pp 67ndash74 2006

[33] H Sun Y Ding J Duan et al ldquoTransesterification of sunfloweroil to biodiesel on ZrO

2supported La

2O3catalystrdquo Bioresource

Technology vol 101 no 3 pp 953ndash958 2010[34] K Jacobson R Gopinath L C Meher and A K Dalai ldquoSolid

acid catalyzed biodiesel production from waste cooking oilrdquoApplied Catalysis B vol 85 no 1-2 pp 86ndash91 2008

[35] A C Alba-Rubio J Santamarıa-Gonzalez J M Merida-Robleset al ldquoHeterogeneous transesterification processes by usingCaO supported on zinc oxide as basic catalystsrdquoCatalysis Todayvol 149 pp 281ndash287 2010

[36] C Samart P Sreetongkittikul and C Sookman ldquoHeterogene-ous catalysis of transesterification of soybean oil using KImes-oporous silicardquo Fuel Processing Technology vol 90 no 7-8 pp922ndash925 2009

[37] J C Juan J Zhang and M A Yarmo ldquo12-Tungstophosphoricacid supported onMCM-41 for esterification of fatty acid undersolvent-free conditionrdquo Journal of Molecular Catalysis A vol267 no 1-2 pp 265ndash271 2007

[38] J Backingham and F Macdonald Dictionary of Organic Com-pounds Chapman and Hall London UK 1996

[39] C-H Lee andY-WChen ldquoEffect of basic additives on PtAl2O3

for CO and propylene oxidation under oxygen-deficient condi-tionsrdquo Industrial and Engineering Chemistry Research vol 36no 5 pp 1498ndash1506 1997

[40] S Therdthianwong C Siangchin and A TherdthianwongldquoImprovement of coke resistance of NiAl

2O3catalyst in CH

4

CO2reforming by ZrO

2additionrdquo Fuel Processing Technology

vol 89 no 2 pp 160ndash168 2008[41] H Hayakawa H Tanaka and K Fujimoto ldquoStudies on precipi-

tated iron catalysts for Fischer-Tropsch synthesisrdquoAppliedCata-lysis A vol 310 no 1-2 pp 24ndash30 2006

[42] W Yu B Wu J Xu Z Tao H Xiang and Y Li ldquoEffect of Ptimpregnation on a precipitated iron-based fischer-tropsch syn-thesis catalystrdquo Catalysis Letters vol 125 no 1-2 pp 116ndash1222008

[43] D Predoi O Crisan A Jitianu et al ldquoIron oxide in a silicamatrix prepared by the sol-gel methodrdquo Thin Solid Films vol515 no 16 pp 6319ndash6323 2007

[44] S Bruni F Cariati M Casu et al ldquoIR and NMR study of nano-particle-support interactions in a Fe

2O3-SiO2nanocomposite

prepared by a sol-gel methodrdquo Nanostructured Materials vol11 no 5 pp 573ndash586 1999

[45] S Bordiga R Buzzoni F Geobaldo et al ldquoStructure and react-ivity of framework and extraframework iron in Fe-silicalite asinvestigated by spectroscopic and physicochemical methodsrdquoJournal of Catalysis vol 158 no 2 pp 486ndash501 1996

[46] P Fabrizioli T Burgi M Burgener S Van Doorslaer and ABaiker ldquoSynthesis structural and chemical properties of ironoxide-silica aerogelsrdquo Journal ofMaterials Chemistry vol 12 no3 pp 619ndash630 2002

[47] M Qing Y Yang B Wu et al ldquoModification of Fe-SiO2inter-

action with zirconia for iron-based Fischer-Tropsch catalystsrdquoJournal of Catalysis vol 279 no 1 pp 111ndash122 2011

[48] S Velusamy andT Punniyamurthy ldquoNovel vanadium-catalyzedoxidation of alcohols to aldehydes and ketones under atmo-spheric oxygenrdquoOrganic Letters vol 6 no 2 pp 217ndash219 2004

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Inorganic ChemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal ofPhotoenergy


Carbohydrate Chemistry

International Journal of


Journal of

Chemistry


Advances in

Physical Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom

Analytical Methods in Chemistry

Journal of

Volume 2014

Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Medicinal ChemistryInternational Journal of


Chromatography Research International


Applied ChemistryJournal of



Theoretical ChemistryJournal of


Journal of

Spectroscopy

Analytical ChemistryInternational Journal of


Journal of


Quantum Chemistry


Organic Chemistry International

ElectrochemistryInternational Journal of



CatalystsJournal of


control of the morphology and crystallinity and preven-tion of the agglomeration Different preparation methodshave been developed in order to obtain desirable samplesand physical properties thermal decomposition ultrasonicspray pyrolysis (USP) chemical vapor deposition and sono-chemical technique [19ndash22] Yin et al reported synthesisof cubic 120572-Fe

2O3(hematite) microparticles via a simple

one-step hydrothermal reaction [23] Iron and iron oxidenanoparticles in silica layers were deposited by sol-gel tech-niques prepared by Simkien et al [24] It was shown thatmultifunctional nanoparticles of different iron oxides pos-sessing various physical properties can be fabricated bymeans of postgrowth annealing of (SiO

2 Fe)SiO

2Si samples

in various atmospheres The hematite maghemite and ironnanoparticles were found to be dominant upon annealing thesamples in air argon and hydrogen atmosphere respectivelyThe synthesis of monodispersed 120574-Fe

2O3nanoparticles by

mechanochemical processing indicated that the nanoparti-cles had a volume-weighted mean diameter of 6 nm and anarrow size distribution with the standard deviation of 3 nm[25] Orolınova et al [26] reported that synthesis of magneticclay composite prepared by the method of precipitation ofiron oxide onto the clay surface was subjected to a heattreatment The sol-gel method has been shown to be veryuseful for preparation of iron oxide nanoparticles dispersedin an amorphous silica matrix Silica is convenient becauseof its nontoxic nature high biocompatibility prevention ofagglomeration temperature resistance chemical inertnessand adjustable pore diameter [27 28]The aim of this study isthe synthesis of magnetic Fe-VSiO

2nanocatalysts promoted

by copper via sol-gel and impregnationmethod for oxidationof organic compounds Characterization of catalysts wascarried out using XRD SEM TPR TGA DSC and N

2

adsorption-desorption measurements We also report themagnetic properties measured by a vibrating sample magne-tometer (VSM)

2 Experimental

21 Synthesis of FeSiO2Nanocatalyst All materials with ana-

lytical purity were purchased from Merck and used withoutfurther purificationThe supported iron catalysts with differ-ent amount of Fe (40 50 60 70 and 80wt) were preparedusing sol-gelmethod Ironnitrate Fe(NO

3)3sdot9H2O tetraetho-

xysilane TEOS and oxalic acid H2C2O4sdot2H2O appropriate

amounts for TEOS hydrolysis are separately dissolved in eth-anol The three solutions were heated up to 50∘C and stirredfor 20min The TEOS was added to the iron nitrate and sub-sequently oxalic acid added to the previous mixture understrong stirring at 60∘C for 2 h The precipitate composed ofiron oxalate and TEOS was progressively hydrolyzed by thehydrationwater of ironnitrate andmainly oxalic acid accord-ing to the following scheme

Si(OC2H5)4+ 4H2O 997888rarr Si(OH)

4+ 4C2H5OH (1)

In the acidic condition (pH asymp 1) Si(OH)4condensed with

other materials to homogeneous gel The monolithic gel wasdried at 110∘C in vacuum for 16 h At last the dried powderwas calcined (450∘C for 6 h) to produce solid magneticcomposite catalyst

22 Synthesis of Fe-VSiO2Catalyst TheFe

2O3SiO2was syn-

thesized in Section 21 and then was impregnated with anaqueous solution containingNH

4VO3(1M) by adding differ-

ent wt of V (119909 = 5ndash20) and results show that 119909 = 15wt isan optimal wt The catalyst containing 40wt Fe-15 wtV was impregnated with 1ndash5wt of CuThe optimal catalystcontaining 40wt Fe-15 wt VSiO

2was promoted with 1ndash

5wt of Cu Then the optimal sample containing 40wtFe-15 wt VSiO

2was promoted with 2wt of Cu dried at

110∘C for 12 h and calcined at different calcination conditions(Figure 1)

23 Catalyst Characterization

231 X-Ray Diffraction (XRD) The XRD patterns of all theprecursor and calcined samples were recorded on a PhilipsXrsquo Pert (40 kV 30mA) X-ray diffractometer using a Cu K120572radiation source (120582 = 1542 A) and a nickel filter in the 2120579range of 4∘ndash70∘

232 N2-Adsorption-Desorption Measurements The specific

surface area (using BET and BJH methods) the total porevolume and themean pore diameter weremeasured using anN2adsorption-desorption isotherm at liquid nitrogen tem-

perature (minus196∘C) using a NOVA 2200 instrument (Quan-tachrome USA) Prior to the adsorption-desorption mea-surements all the samples were degassed at 110∘C in an N

2

flow for 3 h to remove the moisture and other adsorbates

233 Thermal Gravimetric Analysis (TGA) and DifferentialScanning Calorimetry (DSC) The TGA and DSC were car-ried out using simultaneous thermal analyzer (Perkin Elmer)under a flow of dry air with a flow rate of 50mLminminus1 Thetemperature was raised from 20 to 600∘C using a linear pro-grammer at a heating rate of 3∘Cminminus1

234 Scanning Electron Microscopy (SEM) The morpholo-gies of prepared nanocatalysts and their precursors wereobserved bymeans of an S-360Oxford Eng scanning electronmicroscope (USA)

235 Temperature-Programmed Reduction (TPR) TPR pro-files of the Fe

2O3SiO2nanocatalysts were recorded using a

micromeritic TPD-TPR 290 systemTheTPR for each sample(50mg) was performed using a mixture gas of 5 H

295

Ar (vv) as the reductant The sample was heated from 25 to900∘C at a heating rate of 5∘Cmin The flow rate of the mix-ture gas was 50mLminminus1

236 Fourier Transform Infrared (FTIR) Spectrometry TheFT-IR spectra were recorded with a VERTEX 70 (BrukerGermany) FT-IR spectrophotometer equipped with a deu-terium triglycine sulfate (DTGS) detector Samples of 1-2mgwere mixed with 100mg KBr and pressed into translucentdisks at room temperature


Mixing

Aging

Drying

Calcination

FeSiO2nanocatalyst


Gelformation









2catalysts having













2catalyst


2O3(rhombohedral) H

2-TPR profiles












180182184186188190192194196198200

40 50 60 70 80Fe (wt)

Spec

ific s

urfa

ce ar

ea (m

2gminus

1)

(a)

40 50 60 70 800054

0056

0058

006

0062

0064

0066

0068

Pore

dia

met

er (A

)

Fe (wt)

(b)

40 50 60 70 80

15

16

148

152

154

156

158

162

Fe (wt)

Pore

vol

ume (

cm3

gminus1)

(c)



20

10

0

20 30 40 50 60

2120579

Fe2SiO4

Fe2O3




2


2



5 120583m

(a)

1 120583m

(b)


90

70

50

30

10

00 200 400 600

18

16

14

12

10

8

Hea

t flow

(mca

ls)

Wt l

oss (

)

Wei

ght (

mg)

Temperature (∘C)


530∘C

415∘C

0 100 300 500 700 900

Temperature (∘C)

H2

cons

umpt

ion

(au

)










2 1885 1922 1935 744 747 165 16493 1857 187 1892 720 728 1694 16984 1826 1831 1842 710 720 1681 1689

158

160

162

164

166

168

170

172

174

0 5 10 15 20

V (wt)

Spec

ific s

urfa

ce ar

ea (m

2gminus

1)

(a)

0 5 10 15 20

0052

0054

0056

0058

006

0062

0064

0066

0068

007

0072

Pore

dia

met

er (A

)V (wt)

(b)

0 5 10 15 20

14

145

15

155

16

165

17

175

V (wt)

Pore

vol

ume (

cm3

gminus1)

(c)













2catalystThe effect








0 1732 1744 1771 705 712 1748 17612 1796 1785 1813 707 711 1675 16833 1734 1731 1759 624 627 1603 15985 1704 1713 1706 602 608 1596 1582

400

300

200

100

020 30 40 50 60

Fe2O3

Fe3O4

SiO2

2120579 (∘)


nanocatalyst











3O4(cubic) and SiO

2



2interaction



0

005

01

015

02

025

03

035

04

045

0 1000 2000 3000 4000 5000Tr

ansm

ittan

ceWave number


nanocatalyst



2cat-










MP (∘C)found


1

CH2OH CHO

12 Oil minus26

2

CH2OH

MeO

CHO

MeO

18 Oil 0

3

CH2OH

O2N

CHO

O2N20 104 105

4OH

CHO

11 Oil minus75

5

OH O

8 19 20

6

OH O

13 48 48

minus15

minus10

minus5

0

5

10

15

minus10000 minus5000 0 5000 10000

Applied field (Oe)

Mag

netiz

atio

n (e

mu

g)


temperature

4 Conclusions





OH

OH H

R R

RR

R998400 R998400O2 (1 atm)

5 mol nanocatalyst


O

O

C

C R Ar alkyl

R R998400 Ar alkyl

05 eq K2CO3

toluene 100∘C

toluene 100∘C



References














2O3)-MCM-41-SO







3O4nanoparti-



3O4


















3O4)



2O3microparticles














2supported La











2O3catalyst in CH

4

CO2reforming by ZrO























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


Mixing

Aging

Drying

Calcination

FeSiO2nanocatalyst


Gelformation









2catalysts having













2catalyst


2O3(rhombohedral) H

2-TPR profiles












180182184186188190192194196198200

40 50 60 70 80Fe (wt)

Spec

ific s

urfa

ce ar

ea (m

2gminus

1)

(a)

40 50 60 70 800054

0056

0058

006

0062

0064

0066

0068

Pore

dia

met

er (A

)

Fe (wt)

(b)

40 50 60 70 80

15

16

148

152

154

156

158

162

Fe (wt)

Pore

vol

ume (

cm3

gminus1)

(c)



20

10

0

20 30 40 50 60

2120579

Fe2SiO4

Fe2O3




2


2



5 120583m

(a)

1 120583m

(b)


90

70

50

30

10

00 200 400 600

18

16

14

12

10

8

Hea

t flow

(mca

ls)

Wt l

oss (

)

Wei

ght (

mg)

Temperature (∘C)


530∘C

415∘C

0 100 300 500 700 900

Temperature (∘C)

H2

cons

umpt

ion

(au

)










2 1885 1922 1935 744 747 165 16493 1857 187 1892 720 728 1694 16984 1826 1831 1842 710 720 1681 1689

158

160

162

164

166

168

170

172

174

0 5 10 15 20

V (wt)

Spec

ific s

urfa

ce ar

ea (m

2gminus

1)

(a)

0 5 10 15 20

0052

0054

0056

0058

006

0062

0064

0066

0068

007

0072

Pore

dia

met

er (A

)V (wt)

(b)

0 5 10 15 20

14

145

15

155

16

165

17

175

V (wt)

Pore

vol

ume (

cm3

gminus1)

(c)













2catalystThe effect








0 1732 1744 1771 705 712 1748 17612 1796 1785 1813 707 711 1675 16833 1734 1731 1759 624 627 1603 15985 1704 1713 1706 602 608 1596 1582

400

300

200

100

020 30 40 50 60

Fe2O3

Fe3O4

SiO2

2120579 (∘)


nanocatalyst











3O4(cubic) and SiO

2



2interaction



0

005

01

015

02

025

03

035

04

045

0 1000 2000 3000 4000 5000Tr

ansm

ittan

ceWave number


nanocatalyst



2cat-










MP (∘C)found


1

CH2OH CHO

12 Oil minus26

2

CH2OH

MeO

CHO

MeO

18 Oil 0

3

CH2OH

O2N

CHO

O2N20 104 105

4OH

CHO

11 Oil minus75

5

OH O

8 19 20

6

OH O

13 48 48

minus15

minus10

minus5

0

5

10

15

minus10000 minus5000 0 5000 10000

Applied field (Oe)

Mag

netiz

atio

n (e

mu

g)


temperature

4 Conclusions





OH

OH H

R R

RR

R998400 R998400O2 (1 atm)

5 mol nanocatalyst


O

O

C

C R Ar alkyl

R R998400 Ar alkyl

05 eq K2CO3

toluene 100∘C

toluene 100∘C



References














2O3)-MCM-41-SO







3O4nanoparti-



3O4


















3O4)



2O3microparticles














2supported La











2O3catalyst in CH

4

CO2reforming by ZrO























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


180182184186188190192194196198200

40 50 60 70 80Fe (wt)

Spec

ific s

urfa

ce ar

ea (m

2gminus

1)

(a)

40 50 60 70 800054

0056

0058

006

0062

0064

0066

0068

Pore

dia

met

er (A

)

Fe (wt)

(b)

40 50 60 70 80

15

16

148

152

154

156

158

162

Fe (wt)

Pore

vol

ume (

cm3

gminus1)

(c)



20

10

0

20 30 40 50 60

2120579

Fe2SiO4

Fe2O3




2


2



5 120583m

(a)

1 120583m

(b)


90

70

50

30

10

00 200 400 600

18

16

14

12

10

8

Hea

t flow

(mca

ls)

Wt l

oss (

)

Wei

ght (

mg)

Temperature (∘C)


530∘C

415∘C

0 100 300 500 700 900

Temperature (∘C)

H2

cons

umpt

ion

(au

)










2 1885 1922 1935 744 747 165 16493 1857 187 1892 720 728 1694 16984 1826 1831 1842 710 720 1681 1689

158

160

162

164

166

168

170

172

174

0 5 10 15 20

V (wt)

Spec

ific s

urfa

ce ar

ea (m

2gminus

1)

(a)

0 5 10 15 20

0052

0054

0056

0058

006

0062

0064

0066

0068

007

0072

Pore

dia

met

er (A

)V (wt)

(b)

0 5 10 15 20

14

145

15

155

16

165

17

175

V (wt)

Pore

vol

ume (

cm3

gminus1)

(c)













2catalystThe effect








0 1732 1744 1771 705 712 1748 17612 1796 1785 1813 707 711 1675 16833 1734 1731 1759 624 627 1603 15985 1704 1713 1706 602 608 1596 1582

400

300

200

100

020 30 40 50 60

Fe2O3

Fe3O4

SiO2

2120579 (∘)


nanocatalyst











3O4(cubic) and SiO

2



2interaction



0

005

01

015

02

025

03

035

04

045

0 1000 2000 3000 4000 5000Tr

ansm

ittan

ceWave number


nanocatalyst



2cat-










MP (∘C)found


1

CH2OH CHO

12 Oil minus26

2

CH2OH

MeO

CHO

MeO

18 Oil 0

3

CH2OH

O2N

CHO

O2N20 104 105

4OH

CHO

11 Oil minus75

5

OH O

8 19 20

6

OH O

13 48 48

minus15

minus10

minus5

0

5

10

15

minus10000 minus5000 0 5000 10000

Applied field (Oe)

Mag

netiz

atio

n (e

mu

g)


temperature

4 Conclusions





OH

OH H

R R

RR

R998400 R998400O2 (1 atm)

5 mol nanocatalyst


O

O

C

C R Ar alkyl

R R998400 Ar alkyl

05 eq K2CO3

toluene 100∘C

toluene 100∘C



References














2O3)-MCM-41-SO







3O4nanoparti-



3O4


















3O4)



2O3microparticles














2supported La











2O3catalyst in CH

4

CO2reforming by ZrO























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


5 120583m

(a)

1 120583m

(b)


90

70

50

30

10

00 200 400 600

18

16

14

12

10

8

Hea

t flow

(mca

ls)

Wt l

oss (

)

Wei

ght (

mg)

Temperature (∘C)


530∘C

415∘C

0 100 300 500 700 900

Temperature (∘C)

H2

cons

umpt

ion

(au

)










2 1885 1922 1935 744 747 165 16493 1857 187 1892 720 728 1694 16984 1826 1831 1842 710 720 1681 1689

158

160

162

164

166

168

170

172

174

0 5 10 15 20

V (wt)

Spec

ific s

urfa

ce ar

ea (m

2gminus

1)

(a)

0 5 10 15 20

0052

0054

0056

0058

006

0062

0064

0066

0068

007

0072

Pore

dia

met

er (A

)V (wt)

(b)

0 5 10 15 20

14

145

15

155

16

165

17

175

V (wt)

Pore

vol

ume (

cm3

gminus1)

(c)













2catalystThe effect








0 1732 1744 1771 705 712 1748 17612 1796 1785 1813 707 711 1675 16833 1734 1731 1759 624 627 1603 15985 1704 1713 1706 602 608 1596 1582

400

300

200

100

020 30 40 50 60

Fe2O3

Fe3O4

SiO2

2120579 (∘)


nanocatalyst











3O4(cubic) and SiO

2



2interaction



0

005

01

015

02

025

03

035

04

045

0 1000 2000 3000 4000 5000Tr

ansm

ittan

ceWave number


nanocatalyst



2cat-










MP (∘C)found


1

CH2OH CHO

12 Oil minus26

2

CH2OH

MeO

CHO

MeO

18 Oil 0

3

CH2OH

O2N

CHO

O2N20 104 105

4OH

CHO

11 Oil minus75

5

OH O

8 19 20

6

OH O

13 48 48

minus15

minus10

minus5

0

5

10

15

minus10000 minus5000 0 5000 10000

Applied field (Oe)

Mag

netiz

atio

n (e

mu

g)


temperature

4 Conclusions





OH

OH H

R R

RR

R998400 R998400O2 (1 atm)

5 mol nanocatalyst


O

O

C

C R Ar alkyl

R R998400 Ar alkyl

05 eq K2CO3

toluene 100∘C

toluene 100∘C



References














2O3)-MCM-41-SO







3O4nanoparti-



3O4


















3O4)



2O3microparticles














2supported La











2O3catalyst in CH

4

CO2reforming by ZrO























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of





2 1885 1922 1935 744 747 165 16493 1857 187 1892 720 728 1694 16984 1826 1831 1842 710 720 1681 1689

158

160

162

164

166

168

170

172

174

0 5 10 15 20

V (wt)

Spec

ific s

urfa

ce ar

ea (m

2gminus

1)

(a)

0 5 10 15 20

0052

0054

0056

0058

006

0062

0064

0066

0068

007

0072

Pore

dia

met

er (A

)V (wt)

(b)

0 5 10 15 20

14

145

15

155

16

165

17

175

V (wt)

Pore

vol

ume (

cm3

gminus1)

(c)













2catalystThe effect








0 1732 1744 1771 705 712 1748 17612 1796 1785 1813 707 711 1675 16833 1734 1731 1759 624 627 1603 15985 1704 1713 1706 602 608 1596 1582

400

300

200

100

020 30 40 50 60

Fe2O3

Fe3O4

SiO2

2120579 (∘)


nanocatalyst











3O4(cubic) and SiO

2



2interaction



0

005

01

015

02

025

03

035

04

045

0 1000 2000 3000 4000 5000Tr

ansm

ittan

ceWave number


nanocatalyst



2cat-










MP (∘C)found


1

CH2OH CHO

12 Oil minus26

2

CH2OH

MeO

CHO

MeO

18 Oil 0

3

CH2OH

O2N

CHO

O2N20 104 105

4OH

CHO

11 Oil minus75

5

OH O

8 19 20

6

OH O

13 48 48

minus15

minus10

minus5

0

5

10

15

minus10000 minus5000 0 5000 10000

Applied field (Oe)

Mag

netiz

atio

n (e

mu

g)


temperature

4 Conclusions





OH

OH H

R R

RR

R998400 R998400O2 (1 atm)

5 mol nanocatalyst


O

O

C

C R Ar alkyl

R R998400 Ar alkyl

05 eq K2CO3

toluene 100∘C

toluene 100∘C



References














2O3)-MCM-41-SO







3O4nanoparti-



3O4


















3O4)



2O3microparticles














2supported La











2O3catalyst in CH

4

CO2reforming by ZrO























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of




0 1732 1744 1771 705 712 1748 17612 1796 1785 1813 707 711 1675 16833 1734 1731 1759 624 627 1603 15985 1704 1713 1706 602 608 1596 1582

400

300

200

100

020 30 40 50 60

Fe2O3

Fe3O4

SiO2

2120579 (∘)


nanocatalyst











3O4(cubic) and SiO

2



2interaction



0

005

01

015

02

025

03

035

04

045

0 1000 2000 3000 4000 5000Tr

ansm

ittan

ceWave number


nanocatalyst



2cat-










MP (∘C)found


1

CH2OH CHO

12 Oil minus26

2

CH2OH

MeO

CHO

MeO

18 Oil 0

3

CH2OH

O2N

CHO

O2N20 104 105

4OH

CHO

11 Oil minus75

5

OH O

8 19 20

6

OH O

13 48 48

minus15

minus10

minus5

0

5

10

15

minus10000 minus5000 0 5000 10000

Applied field (Oe)

Mag

netiz

atio

n (e

mu

g)


temperature

4 Conclusions





OH

OH H

R R

RR

R998400 R998400O2 (1 atm)

5 mol nanocatalyst


O

O

C

C R Ar alkyl

R R998400 Ar alkyl

05 eq K2CO3

toluene 100∘C

toluene 100∘C



References














2O3)-MCM-41-SO







3O4nanoparti-



3O4


















3O4)



2O3microparticles














2supported La











2O3catalyst in CH

4

CO2reforming by ZrO























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of




MP (∘C)found


1

CH2OH CHO

12 Oil minus26

2

CH2OH

MeO

CHO

MeO

18 Oil 0

3

CH2OH

O2N

CHO

O2N20 104 105

4OH

CHO

11 Oil minus75

5

OH O

8 19 20

6

OH O

13 48 48

minus15

minus10

minus5

0

5

10

15

minus10000 minus5000 0 5000 10000

Applied field (Oe)

Mag

netiz

atio

n (e

mu

g)


temperature

4 Conclusions





OH

OH H

R R

RR

R998400 R998400O2 (1 atm)

5 mol nanocatalyst


O

O

C

C R Ar alkyl

R R998400 Ar alkyl

05 eq K2CO3

toluene 100∘C

toluene 100∘C



References














2O3)-MCM-41-SO







3O4nanoparti-



3O4


















3O4)



2O3microparticles














2supported La











2O3catalyst in CH

4

CO2reforming by ZrO























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


References














2O3)-MCM-41-SO







3O4nanoparti-



3O4


















3O4)



2O3microparticles














2supported La











2O3catalyst in CH

4

CO2reforming by ZrO























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of




2supported La











2O3catalyst in CH

4

CO2reforming by ZrO























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of










Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of

Research Article Preparation and Characterization of ...of cubic -Fe 2 O 3 (hematite) microparticles...

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Transcript of Research Article Preparation and Characterization of ...of cubic -Fe 2 O 3 (hematite) microparticles...