Research Article Kinetic Treatment of the Reaction of...

Research ArticleKinetic Treatment of the Reaction of Fructoseand N-Bromosuccinimide in CationicAnionicNonionic Micelles

Minu Singh

Rungta College of Engineering and Technology Kohka-Kurud Road Bhilai Nagar Durg India

Correspondence should be addressed to Minu Singh minu 0511yahoocoin

Received 2 April 2014 Revised 3 June 2014 Accepted 18 June 2014 Published 30 September 2014

Academic Editor Eri Yoshida

Copyright copy 2014 Minu Singh This is an open access article distributed under the Creative Commons Attribution License whichpermits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

The kinetics of oxidation of fructose by N-bromosuccinimide in acidic medium in the absence and presence of cationic anionicand nonionic surfactants has been measured iodometrically under pseudo-first-order conditionThe oxidation kinetics of fructoseby N-bromosuccinimide shows a first-order dependence on N-bromosuccinimide fractional order dependence on fructose andnegative fractional order dependence on sulfuric acid The kinetics is treated using Berezinrsquos micellar model that was previouslyused for the catalysis and inhibition of the reactionThe determined stoichiometric ratio was 1 1 (fructose N-bromosuccinimide)The variation ofHg(OAC)

2and succinimide (reaction product) has insignificant effect on reaction rate Effects of surfactants added

acrylonitrile added salts and solvent composition variation have been studied Activation parameters for the reaction have beenevaluated from Arrhenius plot by studying the reaction at different temperatures The rate law has been derived on the basis ofobtained data A plausible mechanism has been proposed from the results of kinetic studies reaction stoichiometry and productanalysis

1 Introduction

It is well known that aqueous charged interphases play animportant role in the enhancement of the rate of chemicalreactions [1ndash5] Micelles act as microreactors which bothspeed and inhibit the rates of a wide variety of uni- andbimolecular reactions and shift the equilibrium constants ofmany indicators [6ndash15] Aggregate effects on chemical reac-tivity are generally interpreted by using pseudophase modelswhich treat micelles and water as separate reaction mediathat is separate phases or pseudophases This approachhas been successfully applied to a wide range of chemicalreactions in micellar solution including mixed micelle andin other types of association colloids such asmicroemulsionsand vesicle Surfactant aggregates affect chemical reactivityprimarily by binding or excluding reactants and only secon-darily by changing the free energy of activation [16ndash19]

Considerable attention has centred on N-bromosuc-cinimide (NBS) because of its versatile behaviour asmildoxidant halogenating agent and N-anions which acts

both as bases and nucleophiles NBS is well-known analyticalreagent and the mechanistic aspects of its reactions havebeen documented [20ndash25] As a part of our mechanisticstudies of oxidation of substrate by the NBS I report thekinetics of oxidation of D-fructose by NBS in the micellarregion

Fructose or fruit sugar is a simple monosaccharidefound in many foods It is one of the three importantdietary monosaccharides along with glucose and galactoseHoney tree fruits berries melons and some root vegetablescontain significant amounts of molecular fructose usuallyin combination with glucose stored in the form of sucroseFructose undergoes the Maillard reaction nonenzymaticbrowning with amino acids Fructose readily dehydrates togive hydroxymethylfurfural (ldquoHMFrdquo) This process may inthe future be part of a low-cost carbon-neutral system toproduce replacements for petrol and diesel from plantationsFructose is an excellent humectant and retains moisture fora long period of time even at low relative humidity (RH)Therefore fructose can contribute to improved quality better

Hindawi Publishing CorporationJournal of So MatterVolume 2014 Article ID 791563 10 pageshttpdxdoiorg1011552014791563

2 Journal of Soft Matter

texture and longer shelf life to the food products in which itis used

2 Experimental

21 Material D-Fructose cetyltrimethylammonium bro-mide (CTAB) sodium dodecyl sulfate (SDS) TritonX-100(TX-100) succinimide (NHS) potassium iodide (KI) (all ARs d fine)mercuric acetate (Hg(OAc)

2 GR loba chemie) and

sodium thiosulfate (Na2S2O3sdot2H2O AR Qualigens Exce-

laR Qualigens fine chemicals) used were of highest purityavailable commercially Solutions were prepared in doubledistilled water To maintain hydrogen ion concentrationconstant sulfuric acid (H

2SO4 AR s d fine) was used

Distilled glacial acetic acid (AR s d fine) was used assolvent NBS (Aldrich Germany) solution was standardizediodometrically and stored in an amber coloured bottle toavoid any photochemical deterioration [26]

22 Kinetic Measurements All the kinetic measurementswere carried out in an amber coloured vessel at 313 Kand performed under pseudo-first-order condition with [D-fructose]≫[NBS] The required solutions of all the reactants(except oxidant) were taken in an amber coloured reac-tion vessel to avoid photochemical deterioration [26] Thereaction vessel was kept in the thermostated water bath atfixed temperature and the solution was left to stand for30min to attain equilibrium The reaction was initiated bythe rapid addition of known amounts of D-fructose to areactionmixture containing the required amount of the NBSH2SO4 mercuric acetate acetic acid and water in glass-

stoppered Pyrex boiling tubes and thermostated at 313 KThereaction was initiated with the addition of required volumeof thermally equilibrated oxidant solution The zero timewas taken when NBS solution has been added The progressof the reaction was followed by iodometric estimation ofunconsumed NBS by pipetting out aliquots at different timeintervals The kinetics was monitored for 80 completion ofthe reaction The results are reproducible to within plusmn25with average linear regression coefficient

23 Product Analysis and Stoichiometry Different ratiosof NBS to D-fructose were equilibrated at 313 K in thepresence of a requisite amount of all reactants that issulfuric acid mercuric acetate and acetic acid under thecondition of [NBS] ≫ [D-fructose] for 72 h (when [NBS] =10 times 10

minus3mol dmminus3 then [fructose] = 10 times 10

minus4mol dmminus3and when [NBS] = 50 times 10

minus4mol dmminus3 then [fructose] =10 times 10

minus4mol dmminus3) Estimation of residual [NBS] in eachset showed that 1mol of fructose consumed 1mol of NBSAccordingly the stoichiometric equation was formulated inthe following equation

Product of Fructose Oxidation Consider

fructose + NBS 997888rarr lactone of aldonic acid + NHS (1)

Table 1 Critical micelle concentration (CMC) values of surfactantsin different experimental conditions

Solutions 104 CTABmol dmminus3

103 SDSmol dmminus3

(i) Water 103 915(ii) Fructose 942 523(iii) NBS 990 945(iv) Acetic acid (vv) 90 226(v) H2SO4 820 157(vi) Fructose + NBS + acetic acid(vv) + H2SO4

390 492

Reaction conditions [fructose = 25 times 10minus2 mol dmminus3 [NBS] = 20 times10minus4 mol dmminus3 [Hg(OAc)2] = 50 times 10minus4 mol dmminus3 [H2SO4] = 05 times10minus4 mol dmminus3 and acetic acid (30 (vv)) Literature value at 25∘C cmc ofCTAB is 92 times 10minus4mol dmminus3 SDS is 83 times 10minus3mol dmminus3

After the kinetic experiment was completed a part of theoxidized reaction mixture was treated with alkaline hydroxy-lamine solution and the presence of lactone in the reactionmixture was tested by FeCl

3-HCl blue test [27 28] To the

other part of the reaction mixture barium carbonate wasadded to make the solution neutral [29] FeCl

3solution

that had been coloured violet with phenol when added tothis reaction mixture gave bright-yellow colouration [38]indicating the presence of aldonic acid It is concluded thatlactone formed in the rate-determining step is hydrolyzedto aldonic acid in neutral medium in a fast step At higherpH [lactone] is reduced because of the formation of aldonicacid anion that shifts the equilibrium away from lactone

24 Determination of CMC Values The role of micellarcatalysis may not be understood without its critical micelleconcentration This is the concentration where surfactantwill work as micelle Therefore it is very interesting aswell as important to know this factor very correctly andaccurately The critical micelle concentration (CMC) valuesof surfactants (CTAB SDS TX-100) in the presence andabsence of substrate and oxidants (Table 1) were determinedfrom plots of the specific conductivity (Q) versus surfactantconcentration using conductometric determination methodand carried out with a digital conductivity meter model 611Eat 40∘CThe values of CMC of surfactants are sensitive to thenature of the reactants and also depend upon reaction con-ditions The break point of nearly two straight-line portionsin the plot is taken as an indication of micelle formation andthis corresponds to the CMC of surfactant

3 Results and Discussion

Kinetics due tomolecular bromine interventionwas removedby the addition of mercury (II) ions which removed Brminusions either as HgBr

2or as HgBr

4

2minus Here mercuric acetatewas added as a scavenger Preliminary observations showedthat the solution of CTAB became turbid in presenceof HClO

4 Turbidity increases with [HClO

4] at constant

Journal of Soft Matter 3

Table 2 Effect of substrate oxidant solvent and H2SO4 on 119896obs

102 [fructose] mol dmminus3 104 [NBS] Mol dmminus3 104 [H2SO4] Mol dmminus3 acetic acid (vv) 104 119896obs sminus1

Aqueousa CTABb SDSc

10 20 05 30 080 20 062

25 111 350 086

50 155 540 123

100 20 80 163

200 264 1210 246

25 10 05 30 113 354 088

20 111 350 086

30 111 350 08540 110 350 08450 110 349 084

25 20 050 30 111 350 08610 092 260 070250 065 175 05350 049 132 039100 036 10 031

25 20 05 20 209 525 1025 182 460 09530 111 350 08640 066 230 07750 048 178 065

aReaction conditions [Hg(OAc)2] = 50 times 10minus4mol dmminus3bReaction conditions[Hg(OAc)2] = 50 times 10minus4 mol dmminus3 [CTAB] = 12 times 10minus3 mol dmminus3cReaction conditions [Hg(OAc)2] = 50 times 10minus4 mol dmminus3 [SDS] = 10 times 10minus2 mol dmminus3

[CTAB] Therefore H2SO4was used to maintain the acidic

strength constant

31 Dependence on [Fructose] The effect of varying theconcentrations of fructose on rate in aqueous and micellarmedia showed that the reaction order is fractional Furthera plot of log 119896obs versus log[fructose] was linear with a slopeless than unity (Figure 1) The results are summarized inTable 2

32 Dependence on [NBS] The reaction is of first order in[NBS] in the absence and presence of surfactant as indicatedby the linearity of a plot of log [NBS] versus time (Figure 2)This was further confirmed by the fact that the first-order rateconstant is invariant with different initial concentrations ofNBS (Table 2)

33 Dependence on [H2SO4] The rate constant decreased

with increasing [H2SO4] A plot of log 119896obs versus log

[H2SO4] was linear with a slope that is negative (Figure 4)

and less than unity indicating a negative fractional orderdependence on the rate on [H

2SO4] The results are summa-

rized in Table 2

34 Dependence on Solvent The rate constant decreased withincreasing acetic acid content (20ndash50 [vv]) The results are

summarized in Table 2 A plot of log119870obs versus 1120576was linearwith a negative slope [30] (Figure 3 (2)) Blank experimentsperformed showed that the oxidation of acetic acid by NBSduring the period of study was negligible Consider

log 119896obs = log 119896

1015840

0minus

119885

119860119885

119861119890

2119873

2303 (4120587120576

0) 119889

119860119861119877119879

times

1

120576

(2)

where 119896

1015840

0is the rate constant in a medium of infinite

dielectric constant 119885

119860and 119885

119861are the charges of reacting

ions 119889119860119861

refers to the size of activated complex 119879 is absolutetemperature and 120576 is the dielectric constant of the medium

35 Dependence on [Hg(OAc)2] Mercuric acetate was added

to the reaction mixture as scavenger to eliminate Brminus formedin the reaction which could have produced Br

2in the

reaction The formed Br2thus might cause another parallel

oxidation Hg(OAc)2 thus ensures the oxidation purely

through NBS

36 Dependence on [Succinimide] The reaction rate isretarded by the addition of succinimide (NHS) which is oneof the products of the reactionThis points to the existence ofa preequilibrium step (3) Consider

NBS + H2O1198961

999444999469 HOBr + NHS (3)


0

05

1

15

2

25

0 05 1 15 2 25

aqctab

sds

5+

logk

obs

3 + log[fructose]

Figure 1 Effect of [fructose]withNBS [NBS] = 20times 10minus4mol dmminus3[H2SO4] = 05 times 10minus4mol dmminus3 [Hg(OAc)

2] = 50 times 10minus4mol dmminus3

(⧫) absence of surfactants (◼) [CTAB] = 12 times 10minus3mol dmminus3 (998771)[SDS] = 10times 10minus2mol dmminus3 (k) TX-100 = 10times 10minus3mol dmminus3 30(vv) acetic acid Temp 40∘C

0

02

04

06

08

1

12

0 5 10 15 20 25 30 35 40

log[

NBS

]

aqctab

sds

t (s)

Figure 2 Effect of [NBS] on fructose [fructose] = 25 times

10minus2mol dmminus3 [H2SO4] = 05 times 10minus4mol dmminus3 [Hg(OAc)

2] = 50 times

10minus4mol dmminus3 (⧫) absence of surfactants (◼) [CTAB] = 12 times

10minus3mol dmminus3 (998771) [SDS] = 10 times 10minus2mol dmminus3 (k) TX-100 = 10 times

10minus3mol dmminus3 30 (vv) acetic acid Temp 40∘C

The positive bromine from NBS can be transferred to thefructose through the intermediate formation of HOBr

37 Dependence on [Salt] Added salts inhibit the micellarcatalysis which is a general phenomenonThe inhibition hasbeen explained by assuming that the counterions competewith an ionic reactant for a site on the micelle [31] andcause shape change from spherical to rod-like micelles Theadded salts (KCl KBr and Na

2SO4) inhibit the rate of

reaction As the concentration of these electrolytes increases

002040608

112141618

2

0 05 1 15 2 25 3

aqctab

sds

5+

logk

obs

102 1120576

Figure 3 Effect of acetic acid on fructose [fructose] = 25 times

10minus2mol dmminus3 [NBS] = 20 times 10minus4mol dmminus3 [H2SO4] = 05 times

10minus4mol dmminus3 [Hg(OAc)2] = 50 times 10minus4mol dmminus3 (⧫) absence of

surfactants (◼) [CTAB] = 12 times 10minus3mol dmminus3 (998771) [SDS] = 10 times

10minus2mol dmminus3 (k) TX-100 = 10 times 10minus3mol dmminus3 Temp 40∘C

0

02

04

06

08

1

12

14

16

18

0 05 1 15 2 25

aqctab

sds

5+

logk

obs

3 + log[H2SO4]

Figure 4 Effect of [H2SO4] [fructose] = 25 times 10minus2mol dmminus3

[NBS] = 20 times 10minus4mol dmminus3 [Hg(OAc)2] = 50 times 10minus4mol dmminus3

(⧫) absence of surfactants (◼) [CTAB] = 12 times 10minus3mol dmminus3 (998771)[SDS] = 10 times 10minus2mol dmminus3 30 (vv) acetic acid (k) TX-100 =10 times 10minus3mol dmminus3 Temp 40∘C

the concentration of reactants at the reaction site decreasesbecause these are responsible for rate inhibition of micellar-mediated reactions due to the exclusion of the reagent(s) fromthe micellar pseudophase

38 Assessment for Acrylonitrile Polymerization Additionof acrylonitrile to the reaction mixture does not inducepolymerization Therefore the reaction does not involve theformation of free radicalsThe observations demonstrate thatno free radicals are formed in the reaction mechanism


Table 3 Effect of temperature on 119896obs

∘C temperature 104 119896obs sminus1

(Aqueousa) (CTABb) (SDSc)30 057 182 04935 079 289 06740 111 350 08645 148 408 12150 188 563 170Activation parameters119864

119886(kJmolminus1) 4769 4069 4827

log119901

119911(dm3 molminus1 secminus1) 40 333 399

Δ119867 (kJmolminus1) 4509 3809 4567minusΔ119878 (JKminus1molminus1) 32096 31143 32308Δ119866 (kJmolminus1) 14555 13556 14697aReaction conditions [fructose] = 25 times 10minus2 mol dmminus3 [NBS] = 20 times10minus4 mol dmminus3 [H2SO4] = 05 times 10minus4 mol dmminus3 [Hg(OAc)2] = 50 times10minus4 mol dmminus3 and 30 acetic acid (vv)bReaction conditions [fructose] = 25 times 10minus2 mol dmminus3 [NBS] = 20 times10minus4 mol dmminus3 [H2SO4] = 05 times 10minus4 mol dmminus3 [Hg(OAc)2] = 50 times10minus4 mol dmminus3 [CTAB] = 12 times 10minus3 mol dmminus3 and 30 acetic acid (vv)cReaction conditions [fructose] = 25 times 10minus2 mol dmminus3 [NBS] = 20 times10minus4 mol dmminus3 [H2SO4] = 05 times 10minus4 mol dmminus3 [Hg(OAc)2] = 50 times10minus4 mol dmminus3 [SDS] = 10 times 10minus2 mol dmminus3 and 30 acetic acid (vv)

39 Temperature Effect and Activation Parameters The oxi-dation of fructose was studied at 30ndash50∘C and the dataare presented in Table 3 Arrhenius parameters evaluatedfrom linear plots of log 119896obs versus 1119879 were computed fromArrhenius and Eyring equations (Figure 5) in Table 3 Thecatalytic behavior of CTAB and TX-100 micelles indicatesthat the complex of fructose-NBShas the negative chargeThecationic head group may form an ion pair with the reactiveand existing complex of fructose-NBS As a result a largenumber of fructose-NBS complexes are incorporated into thesmall volume of cationic micelles But the nonionic micellesform hydrogen bond with the fructose-NBS complex In thepresence of SDS on the other hand there is electrostaticrepulsion between the negative head group of SDS micellesand the reactive species of fructose-NBS complex The resultis that slightly inhibitory effect is possible A higher value of119864

119886in the presence of SDS shows the slightly inhibitory effect

on the rate of reaction whereas a low value in the presenceof CTAB and TX-100 shows the catalytic effect The largenegative value of Δ119878

in the presence of CTAB and TX-100indicates that more ordered activated complex is formedThe fairly high positive values of Δ119867

and Δ119866

indicate thatthe transition state is highly solvated The nearly same valueof Δ119866

in the absence and presence of surfactant indicatedoperation of similar reaction mechanism in both cases Here119864

119886is energy of activation Δ119867

is enthalpy of activation Δ119878is entropy of activation and Δ119866

is free entropy of activation

310 Mechanism The monosaccharides are considered asa unit of disaccharides and on hydrolysis disaccharidesgive monosaccharide units D-sucrose hydrolyzes into twomonosaccharidesmdashglucose and fructose The monosaccha-rides are considered as a polyol and the reactivities of ndashOH

002040608

112141618

2

305 31 315 32 325 33 335

aqctab

sds

5+

logk

obs

103 1T

Figure 5 Effect of temperature [fructose] = 25 times 10minus2mol dmminus3[NBS] = 20 times 10minus4mol dmminus3 [H

2SO4] = 05 times 10minus4mol dmminus3

[Hg(OAc)2] = 50 times 10minus4mol dmminus3 (⧫) absence of surfactants (◼)

[CTAB] = 12 times 10minus3mol dmminus3 (998771) [SDS] = 10 times 10minus2mol dmminus3 (k)TX-100 = 10 times 10minus3mol dmminus3 30 (vv) acetic acid

groups can be influenced by the presence of the carbonylgroup Monosaccharides exist mainly as pyranoid and fura-noid forms with the former being more stable [32]

On the other hand NBS exists in the following equilibria

Reactive Species of NBS in Aqueous Medium Consider

NBS + H2O 999445999468 NHS + HOBr (4)

HOBr + H+ 999445999468 (H2OBr)+ (5)

NBS + H+ 999445999468 (NBSH)

+ (6)

NBS + H+ 999445999468 NHS + Br+ (7)

Since on assumption of NBS or (NBSH)

+ as the reactivespecies the rate law fails to explain the negative effectof phthalimide hence neither of these species NBS and(NBSH)

+ can be taken as the reactive speciesWhenHOBr istaken as the reactive species the rate law explains the negativeeffect of [H+] and [NHS] Thus HOBr is taken as the mostreactive species which gave the rate law capable of explainingall the kinetic observations and other effects

According to above experimental conditions HOBr is themost reactive species of NBS and considering the fact thatone mole of D-sucrose is oxidized by two moles of NBS inScheme 2

In Scheme 2 119878 stands for D-sucrose 119870

1 119870

2are the

equilibrium constants for steps 1 and 2 119896 is the rate constantand Aminus is intermediate species Equation (8) is in good agree-ment with the experimental resultsThe rate of disappearanceof [NBS] can be expressed in (10) Equations (11) and (12)


H

H

O

(OH CH2OH) (OH CH2OH)

HOH2CO

120572- and 120573-D-fructopyranose(58)

120572- and 120573-D-fructofuranose(42)

Scheme 1 Species of D-sucrose

O

O

O

OO

NndashBr ++ H2Ok1

kminus1NndashH HOBr

N-bromosuccinimide Succinimide

O

HOBrOH

CH2OH

+

+ +

+k2

kminus2fast

OndashBr H3O+

CH2Ominus

Fructose

O

O

O

OndashBr

CH2ndashOminus

kW

Slow

Lactone of aldonic acid Formaldehyde

O

Brminus CH H

(7)

(12)

(13)

∙∙

∙∙

Aminus

Scheme 2 Mechanism of oxidation of fructose by NBS

satisfactorily explain the kinetic results with respect to [NBS][D-sucrose] [H

2SO4] and [NHS] Consider

minus

119889 [NBS]119889119905

=

119896119896

1119896

2 [Fructose] [NBS]119879

[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(8)

where

[NBS]119879

= [NBS] + [HOBr] + [Aminus] (9)

rate = 119896obs[NBS]119879 (10)

119896obs =

rate[NBS]119879

=

119896119896

1119896

2 [Fructose]

[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(11)

1

119896obs=

[H+] [NHS]119896119896

1119896

2 [Fructose]

+

[H+]119896119896

2 [Fructose]

+

1

119896

(12)

311 Effect of Varying [Surfactants] In the case of D-sucrosethe cationic surfactant CTAB and nonionic surfactant TX-100 have been found to show the rate accelerating effectwhereas the anionic surfactant SDS has been found to showthe rate retarding effect In all cases after a certain con-centration of surfactant the rate constant attains a limitingvalue In presence of the cationic surfactant CTAB boththe reactants that is D-sucrose (it should hydrolyse intoglucose and fructose with negative charge) and NBS arepreferably partitioned in the stern layer of CTAB (a cationicsurfactant) bearing the positively charged micellar headgroups and consequently the rate is accelerated (Figures 6and 7) (Table 4) In presence of the nonionic surfactant TX-100 both the reactants that is D-sucrose (a hydrophilicsubstance) and NBS are preferably partitioned in the sternlayer of TX-100 (a nonionic surfactant) bearing not anycharge on micellar head groups and consequently the rateis accelerated The anionic species of D-sucrose (Scheme 1)and NBS is being repelled by the negatively charged micellarhead groups of SDS (an anionic surfactant) and consequentlythe rate is retarded (Figures 8 and 9) (Table 4) A possible


Table 4 Effect of surfactants on 119896obs

103 [CTAB] mol dmminus3 104 119896obs sminus1 102 [SDS]

mol dmminus3 104 119896obs sminus1

0 111 0 11102 125 02 10204 131 04 1006 150 06 09708 216 075 09310 290 08 09112 350 10 08614 240 11 08416 20 12 08118 172 14 078

16 mdashOther parameters119896

119908 sminus1 (10minus4) 107 131

(119870119878+ 119870

119874) dm3 molminus1

(10minus6) 257 341

Reaction conditions [fructose] = 25 times 10minus2mol dmminus3 [NBS] = 20 times10minus4mol dmminus3 [H2SO4] = 05 times 10minus4mol dmminus3 [Hg(OAc)2] = 50 times10minus4mol dmminus3 30 acetic acid (vv) and temperature 40∘C

0

05

1

15

2

25

3

35

4

0 05 1 15 2

Fructose

104k

obssminus

1

103 CTAB (mol dmminus3)

Figure 6 Effect of [CTAB] on fructose [fructose] = 25 times


2] = 50 times

10minus4mol dmminus3 [NBS] = 20 times 10minus4mol dmminus3 30 (vv) acetic acidTemp 40∘C

arrangement (although highly schematic) could be as shownin Scheme 3 which indicates the probable reaction site to bethe ldquoStern and Gouy-Chapman layersrdquo junctural region

312 The Kinetic Model to Explain the Micellar Effects Micel-lar catalysis critically depends on the interactions of themicelle with the substrate(s) and the activated complex Thisis an extremely complicated problem because a number ofdifferent interactions are involved including those associatedwith the head group of the surfactant the different segmentsof the alkyl chain and the counterions In Berezinrsquos model

0

01

02

03

04

05

06

07

08

09

1

0 5 10 15 20 25 30

Fructose

104 (Csurf-CMC) (mol dmminus3)

10minus4k

obsminus

1s

Figure 7 Plot between (119862surf-CMC) versus 119896

minus1

obs (For CTAB)[fructose] = 25 times 10minus2mol dmminus3 [NBS] = 20 times 10minus4mol dmminus3[H2SO4] = 05 times 10minus4mol dmminus3 [Hg(OAc)


30 (vv) acetic acid Temp 40∘C

0

02

04

06

08

1

12

0 02 04 06 08 1 12 14 16

Fructose

104k

obssminus

1

102 [SDS] (mol dmminus3)

Figure 8 Effect of [SDS] on fructose [fructose] = 25 times


2] = 50 times


a solution above the CMC may be considered as a two-phase system consisting of an aqueous phase and a micellarpseudophase The reactants (S and O) may be distributedas shown in Scheme 4 A quantitative rate expression for abimolecular reaction occurring only in aqueous (119896

119882path)

and micellar (119896119872

path) phase for the pseudo-first-order rateconstant is given in Scheme 4 Consider

119896obs =

119896

119882+ 119896

1015840

119872119870S119870O (119862surf minus CMC)

[1 + 119870S (119862surf minus CMC)] [1 + 119870O (119862surf minus CMC)]

(13)

where 119870S and 119870O are the association constants of D-sucroseand NBS respectively with surfactants 119862surf is the analyticalconcentration of surfactants 1198961015840

119872= (119896119872

119881) 119881 is the molar


H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2OH2O

H2O

H2O

H2O

H2O

H2O

H2 O

Hydrolysis

Hydrolysis

Fructose 2HOBr

2HOBr

kW

Products

ProductskM

Brminus

Brminus Brminus

Br minusCH3

CH3

CH3

CH3

CH3

CH3

CH3

CH3

+

+

+

+

+

Fructose +

Core

Stern layer

Gouy-Chapman layer

Micellar surface

H 3CndashN

H3CndashN H3CndashN

H3 CndashN

Scheme 3 Schematic model showing probable location of reactants

(C6H12O6)W + (NBS)WkW (Product)W

(C6H12O6)M + (NBS)MkM

(Product)M

KS KO

Scheme 4 Berezinrsquos model

volume of the micelle and 119896

119882and 119896

119872are the pseudo-first-

order rate constants in absence and presence of micellesrespectively Since the oxidant will be uncharged speciesand the substrate is large molecules the hydrophobic andelectrostatic interactions will be large and hence it may beexpected that 119870S and 119870O will be high Since 119862surf is small itmay be possible that 119896

119882≫ 119896

1015840

119872119870S119870O (119862surf minus CMC) so that

(13) takes the form

119896obs

=

119896

119882

1 + (119870S + 119870O) (119862surf minus CMC) + 119870S119870O(119862surf minus CMC)

2

(14)

Again since (119862surf minusCMC) is very small the terms containing(119862surf minus CMC)

2may be neglected and (14)may be rearrangedto

1

119896obs=

1

119896

119882

+

119870S + 119870O119896

119882

(119862surf minus CMC) (15)

Plot of 119896

minus1

obs versus (119862surf minus CMC) for D-sucrose is linear(Figures 7 and 9)

4 Summary

In summary the following conclusions can be drawn Kineticparameters for the reaction were determined assuming thatthe dominant active species of NBS is HOBr Activationand thermodynamic parameters have been evaluated forboth in absence and presence of the surfactants The CMCvalues are lower than those given in the literature foraqueous solutions of surfactants without added electrolyteThe reaction was found to be first and fractional order eachwith respect to the oxidant and the reductant The mech-anism of the reaction involves (i) hydrolysis of D-sucroseinto monosaccharide units glucose and fructose and (ii)oxidation of both monosaccharide units Oxidation productis lactone of aldonic acid The rate of oxidation increaseswith increasing concentration of CTAB and TX-100The SDSshows inhibitory effect The effect of micellization can becorrelated with the nature of the reducing substrates and


0

02

04

06

08

1

12

14

0 5 10 15 20 25

Fructose

103 (C surf-CMC) (mol dmminus3)

10minus4k

obsminus

1s


minus1

obs (For SDS) [fruc-tose] = 25 times 10minus2mol dmminus3 [NBS] = 20 times 10minus4mol dmminus3 [H

2SO4]

= 05 times 10minus4mol dmminus3 [Hg(OAc)2] = 50 times 10minus4mol dmminus3 30 (vv)

acetic acid Temp 40∘C

the reaction conditions This is in agreement with the qual-itative knowledge about the nature of D-sucrose and NBS inH2SO4medium

Conflict of Interests

The author declares that there is no conflict of interestsregarding the publication of this paper

Acknowledgments

Theauthor gratefully wishes to thank theChhattisgarhCoun-cil of Science and Technology (CGCOST) for the ResearchProject Grant The author also thanks Professor Laurence SRomstedDepartment of ChemistryWright-RiemanLabora-tories New Jersey USA for valuable discussions and fruitfulsuggestions

References

[1] JW ParkM-A Chung and KM Choi ldquoProperties of sodiumdodecyl sulfateTriton X-100 mixed micellerdquo Bulletin of theKorean Chemical Society vol 10 no 5 pp 437ndash442 1989

[2] B Samiey K Alizadeh M A Moghaddasi M F Mousavi andN Alizadeh ldquoStudy of kinetics of Bromophenol blue fadingin the presence of SDS DTAB and Triton X-100 by classicalmodelrdquo Bulletin of the Korean Chemical Society vol 25 no 5pp 726ndash736 2004

[3] H Gharibi B Sohrabi S Javadian and M HashemianzadehldquoStudy of the electrostatic and steric contributions to the freeenergy of ionicnonionic mixed micellizationrdquo Colloids andSurfaces A Physicochemical and Engineering Aspects vol 244no 1ndash3 pp 187ndash196 2004

[4] Z Zhi-Guo and Y Hong ldquoInteraction of nonionic surfactantAEO9with ionic surfactantsrdquo Journal of Zhejiang University

Science B vol 6 no 6 pp 597ndash601 2005

[5] G Briganti S Puvvada and D Blankschtein ldquoEffect of ureaon micellar properties of aqueous solutions of nonionic surfac-tantsrdquo Journal of Physical Chemistry vol 95 no 22 pp 8989ndash8995 1991

[6] H H Paradies The Journal of Physical Chemistry A vol 84 p599 1980

[7] A B Mandal B U Nair and D Ramaswamy ldquoDeterminationof the critical micelle concentration of surfactants and thepartition coefficient of an electrochemical probe by using cyclicvoltammetryrdquo Langmuir vol 4 no 3 pp 736ndash739 1988

[8] T van den Boomgaard and J Lyklema ldquoOn the influence ofconcentrated electrolytes on the association behaviour of a non-ionic surfactantrdquo Progress in Colloid and Polymer Science vol68 pp 25ndash32 1983

[9] J P Hanrahan K J Ziegler J P Galvin and J D HolmesldquoWater-in-CO

2emulsions reaction vessels for the production

of tetra-ethyl pyronerdquo Langmuir vol 20 no 11 pp 4386ndash43902004

[10] S K Mehta A K Malik U Gupta and A L J Rao ElectronicJournal of Environmental Agricultural and Food Chemistry vol3 no 6 p 784 2004

[11] N J Turro P-L Kuo P Somasundaran and K Wong ldquoSurfaceand bulk interactions of ionic and nonionic surfactantsrdquo TheJournal of Physical Chemistry vol 90 no 2 pp 288ndash291 1986

[12] A B Mandal D V Ramesh and S C Dhar ldquoPhysico-chemical studies of micelle formation on sepia cartilage col-lagen solutions in acetate buffer and its interaction with ionicand nonionic micelles Hydrodynamic and thermodynamicstudiesrdquo European Journal of Biochemistry vol 169 no 3 pp617ndash628 1987

[13] H-K Ko B-D Park and J-C Lim ldquoStudies on phase behaviorin systems containing NP series nonionic surfactant waterand D-limonenerdquo Journal of Korean Industrial and EngineeringChemistry vol 11 no 6 pp 679ndash686 2000

[14] A Rodrıguez M Munoz M del Mar Graciani S FernandezChacon and M L Moya ldquoKinetic study in water-ethyleneglycol cationic zwitterionic nonionic and anionic micellarsolutionsrdquo Langmuir vol 9 no 3 pp 9945ndash9952 2004

[15] N J Buurma A M Herranz and J B F N Engberts ldquoThenature of the micellar Stern region as studied by reactionkineticsrdquo Journal of the Chemical SocietymdashPerkin Transactionsvol 2 no 1 pp 113ndash119 1999

[16] M Munoz A Rodrıguez and M del Mar Graciani ldquoStudyof the reaction 111-trichloro-22-bis(p-chlorophenyl)ethane +OHminus in nonionic micellar solutionsrdquo Langmuir vol 15 pp7876ndash7879 1999

[17] J Perkowski J Mayer and L Kos ldquoReactions of non-ionicsurfactants triton X-n type with OH radicals A reviewrdquoFibresamp Textiles in Eastern Europe vol 13 no 2 pp 81ndash85 2005

[18] F Mahmood M Arif A Ahmed and S B Niazi ldquoInteractionstudies of tween-40 with some acidic species at 20 Crdquo Journal ofResearch (Science) vol 11 no 1 p 1 2000

[19] Kabir-ud-Din A M A Morshed and Z Khan ldquoInfluence ofsodium dodecyl sulfateTritonX-100 micelles on the oxidationof D-fructose by chromic acid in presence of HClO

4rdquo Carbohy-

drate Research vol 337 no 17 pp 1573ndash1583 2002[20] K-H Chung and S Kim ldquoOxidations of cyclohexanols by N-

bromosuccinimide and sodium hypochloriterdquo Bulletin of theKorean Chemical Society vol 7 no 2 pp 111ndash113 1986

[21] S P Mushran K Singh L Pandey and S M Pandey Proceed-ings of the Indian National Science Academy vol 46 no 2 p 1191980


[22] S K Mavalangi M R Kembhavi and S T NandibewoorldquoOxidation of ethylenediaminetetraacetic acid by N-bromosuccinimide in aqueous alkaline mediummdasha kineticstudyrdquo Turkish Journal of Chemistry vol 25 no 3 pp 355ndash3632001

[23] N A M Farook ldquoKinetics and mechanism of oxidation of4-oxoacids by N-bromosuccinimide in aqueous acetic acidmediumrdquo Journal of the Iranian Chemical Society vol 3 no 4pp 378ndash386 2006

[24] R Ramachandrappa S M Mayanna and N M Made GowdaldquoKinetics and mechanism of oxidation of aspirin bybromamine-T N-bromosuccinimide and N-bromophth-alimiderdquo International Journal of Chemical Kinetics vol 30 no6 pp 407ndash414 1998

[25] S Pandey and S K Upadhyay Indian Journal of ChemicalTechnology vol 12 no 1 p 35 2005

[26] M Z Barakat and M F A El-Wahab ldquoMicrodeterminationof bromine or chlories in N-halogenated imidesrdquo AnalyticalChemistry vol 26 no 12 pp 1973ndash1974 1954

[27] K K Sengupta B A Begum and B B Pal ldquoKinetic behaviourand relative reactivities of some aldoses amino sugars andmethylated sugars towards platinum(IV) in alkaline mediumrdquoCarbohydrate Research vol 309 no 4 pp 303ndash310 1998

[28] A Kumar and R N J Mehrotra ldquoKinetics of oxidation of AldoSugars by quinquevalent vanadium ion in acid mediumrdquo TheJournal of Organic Chemistry vol 40 pp 1248ndash1252 1975

[29] K K Sengupta B A Begum and B B Pal ldquoKinetics andmechanism of the oxidation of some aldoses amino sugarsand methylated sugars by tris(pyridine-2-carboxylato)man-ganese(III) in weakly acidic mediumrdquo Carbohydrate Researchvol 315 no 1-2 pp 70ndash75 1999

[30] E S Amis Solvent Effects on Reaction Rates and MechanismAcademic Press New York NY USA 1966

[31] A Ray and G Nemethy ldquoEffects of ionic protein denaturantson micelle formation by nonionic detergentsrdquo Journal of theAmerican Chemical Society vol 93 no 25 pp 6787ndash6793 1971

[32] A S Perlin ldquoRing contraction during the lead tetraacetateoxidation of reducing sugarsrdquo Canadian Journal of Chemistryvol 42 pp 2365ndash2374 1964

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

High Energy PhysicsAdvances in

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014


FluidsJournal of

Atomic and Molecular Physics

Journal of



Advances in Condensed Matter Physics

OpticsInternational Journal of



AstronomyAdvances in

International Journal of


Superconductivity


Statistical MechanicsInternational Journal of


GravityJournal of


AstrophysicsJournal of


Physics Research International


Solid State PhysicsJournal of

Computational Methods in Physics

Journal of



Soft MatterJournal of

Hindawi Publishing Corporationhttpwwwhindawicom

AerodynamicsJournal of

Volume 2014


PhotonicsJournal of


Journal of

Biophysics


ThermodynamicsJournal of


texture and longer shelf life to the food products in which itis used

2 Experimental

21 Material D-Fructose cetyltrimethylammonium bro-mide (CTAB) sodium dodecyl sulfate (SDS) TritonX-100(TX-100) succinimide (NHS) potassium iodide (KI) (all ARs d fine)mercuric acetate (Hg(OAc)

2 GR loba chemie) and

sodium thiosulfate (Na2S2O3sdot2H2O AR Qualigens Exce-

laR Qualigens fine chemicals) used were of highest purityavailable commercially Solutions were prepared in doubledistilled water To maintain hydrogen ion concentrationconstant sulfuric acid (H

2SO4 AR s d fine) was used

Distilled glacial acetic acid (AR s d fine) was used assolvent NBS (Aldrich Germany) solution was standardizediodometrically and stored in an amber coloured bottle toavoid any photochemical deterioration [26]

22 Kinetic Measurements All the kinetic measurementswere carried out in an amber coloured vessel at 313 Kand performed under pseudo-first-order condition with [D-fructose]≫[NBS] The required solutions of all the reactants(except oxidant) were taken in an amber coloured reac-tion vessel to avoid photochemical deterioration [26] Thereaction vessel was kept in the thermostated water bath atfixed temperature and the solution was left to stand for30min to attain equilibrium The reaction was initiated bythe rapid addition of known amounts of D-fructose to areactionmixture containing the required amount of the NBSH2SO4 mercuric acetate acetic acid and water in glass-

stoppered Pyrex boiling tubes and thermostated at 313 KThereaction was initiated with the addition of required volumeof thermally equilibrated oxidant solution The zero timewas taken when NBS solution has been added The progressof the reaction was followed by iodometric estimation ofunconsumed NBS by pipetting out aliquots at different timeintervals The kinetics was monitored for 80 completion ofthe reaction The results are reproducible to within plusmn25with average linear regression coefficient

23 Product Analysis and Stoichiometry Different ratiosof NBS to D-fructose were equilibrated at 313 K in thepresence of a requisite amount of all reactants that issulfuric acid mercuric acetate and acetic acid under thecondition of [NBS] ≫ [D-fructose] for 72 h (when [NBS] =10 times 10

minus3mol dmminus3 then [fructose] = 10 times 10

minus4mol dmminus3and when [NBS] = 50 times 10

minus4mol dmminus3 then [fructose] =10 times 10

minus4mol dmminus3) Estimation of residual [NBS] in eachset showed that 1mol of fructose consumed 1mol of NBSAccordingly the stoichiometric equation was formulated inthe following equation

Product of Fructose Oxidation Consider

fructose + NBS 997888rarr lactone of aldonic acid + NHS (1)

Table 1 Critical micelle concentration (CMC) values of surfactantsin different experimental conditions

Solutions 104 CTABmol dmminus3

103 SDSmol dmminus3

(i) Water 103 915(ii) Fructose 942 523(iii) NBS 990 945(iv) Acetic acid (vv) 90 226(v) H2SO4 820 157(vi) Fructose + NBS + acetic acid(vv) + H2SO4

390 492

Reaction conditions [fructose = 25 times 10minus2 mol dmminus3 [NBS] = 20 times10minus4 mol dmminus3 [Hg(OAc)2] = 50 times 10minus4 mol dmminus3 [H2SO4] = 05 times10minus4 mol dmminus3 and acetic acid (30 (vv)) Literature value at 25∘C cmc ofCTAB is 92 times 10minus4mol dmminus3 SDS is 83 times 10minus3mol dmminus3

After the kinetic experiment was completed a part of theoxidized reaction mixture was treated with alkaline hydroxy-lamine solution and the presence of lactone in the reactionmixture was tested by FeCl

3-HCl blue test [27 28] To the

other part of the reaction mixture barium carbonate wasadded to make the solution neutral [29] FeCl

3solution

that had been coloured violet with phenol when added tothis reaction mixture gave bright-yellow colouration [38]indicating the presence of aldonic acid It is concluded thatlactone formed in the rate-determining step is hydrolyzedto aldonic acid in neutral medium in a fast step At higherpH [lactone] is reduced because of the formation of aldonicacid anion that shifts the equilibrium away from lactone

24 Determination of CMC Values The role of micellarcatalysis may not be understood without its critical micelleconcentration This is the concentration where surfactantwill work as micelle Therefore it is very interesting aswell as important to know this factor very correctly andaccurately The critical micelle concentration (CMC) valuesof surfactants (CTAB SDS TX-100) in the presence andabsence of substrate and oxidants (Table 1) were determinedfrom plots of the specific conductivity (Q) versus surfactantconcentration using conductometric determination methodand carried out with a digital conductivity meter model 611Eat 40∘CThe values of CMC of surfactants are sensitive to thenature of the reactants and also depend upon reaction con-ditions The break point of nearly two straight-line portionsin the plot is taken as an indication of micelle formation andthis corresponds to the CMC of surfactant

3 Results and Discussion

Kinetics due tomolecular bromine interventionwas removedby the addition of mercury (II) ions which removed Brminusions either as HgBr

2or as HgBr

4

2minus Here mercuric acetatewas added as a scavenger Preliminary observations showedthat the solution of CTAB became turbid in presenceof HClO

4 Turbidity increases with [HClO

4] at constant




Aqueousa CTABb SDSc

10 20 05 30 080 20 062

25 111 350 086

50 155 540 123

100 20 80 163

200 264 1210 246

25 10 05 30 113 354 088

20 111 350 086

30 111 350 08540 110 350 08450 110 349 084

25 20 050 30 111 350 08610 092 260 070250 065 175 05350 049 132 039100 036 10 031

25 20 05 20 209 525 1025 182 460 09530 111 350 08640 066 230 07750 048 178 065



strength constant








rized in Table 2



log 119896obs = log 119896

1015840

0minus

119885

119860119885

119861119890

2119873

2303 (4120587120576

0) 119889

119860119861119877119879

times

1

120576

(2)

where 119896

1015840



119860and 119885


ions 119889119860119861




2in the



through NBS


NBS + H2O1198961

999444999469 HOBr + NHS (3)


0

05

1

15

2

25

0 05 1 15 2 25

aqctab

sds

5+

logk

obs

3 + log[fructose]




0

02

04

06

08

1

12

0 5 10 15 20 25 30 35 40

log[

NBS

]

aqctab

sds

t (s)



2] = 50 times








002040608

112141618

2

0 05 1 15 2 25 3

aqctab

sds

5+

logk

obs

102 1120576






0

02

04

06

08

1

12

14

16

18

0 05 1 15 2 25

aqctab

sds

5+

logk

obs

3 + log[H2SO4]










119886(kJmolminus1) 4769 4069 4827

log119901







and Δ119866







002040608

112141618

2

305 31 315 32 325 33 335

aqctab

sds

5+

logk

obs

103 1T








NBS + H2O 999445999468 NHS + HOBr (4)

HOBr + H+ 999445999468 (H2OBr)+ (5)

NBS + H+ 999445999468 (NBSH)

+ (6)

NBS + H+ 999445999468 NHS + Br+ (7)






1 119870

2are the



H

H

O


HOH2CO




O

O

O

OO

NndashBr ++ H2Ok1

kminus1NndashH HOBr


O

HOBrOH

CH2OH

+

+ +

+k2

kminus2fast

OndashBr H3O+

CH2Ominus

Fructose

O

O

O

OndashBr

CH2ndashOminus

kW

Slow


O

Brminus CH H

(7)

(12)

(13)

∙∙

∙∙

Aminus




minus

119889 [NBS]119889119905

=

119896119896

1119896


[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(8)

where

[NBS]119879


rate = 119896obs[NBS]119879 (10)

119896obs =

rate[NBS]119879

=

119896119896

1119896

2 [Fructose]

[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(11)

1

119896obs=

[H+] [NHS]119896119896

1119896

2 [Fructose]

+

[H+]119896119896

2 [Fructose]

+

1

119896

(12)






0 111 0 11102 125 02 10204 131 04 1006 150 06 09708 216 075 09310 290 08 09112 350 10 08614 240 11 08416 20 12 08118 172 14 078


119908 sminus1 (10minus4) 107 131

(119870119878+ 119870


(10minus6) 257 341


0

05

1

15

2

25

3

35

4

0 05 1 15 2

Fructose

104k

obssminus

1




2] = 50 times




0

01

02

03

04

05

06

07

08

09

1

0 5 10 15 20 25 30

Fructose


10minus4k

obsminus

1s


minus1




0

02

04

06

08

1

12

0 02 04 06 08 1 12 14 16

Fructose

104k

obssminus

1




2] = 50 times



119882path)



119896obs =

119896

119882+ 119896

1015840

119872119870S119870O (119862surf minus CMC)


(13)


119872= (119896119872

119881) 119881 is the molar


H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2OH2O

H2O

H2O

H2O

H2O

H2O

H2 O

Hydrolysis

Hydrolysis

Fructose 2HOBr

2HOBr

kW

Products

ProductskM

Brminus

Brminus Brminus

Br minusCH3

CH3

CH3

CH3

CH3

CH3

CH3

CH3

+

+

+

+

+

Fructose +

Core

Stern layer

Gouy-Chapman layer

Micellar surface

H 3CndashN

H3CndashN H3CndashN

H3 CndashN




(Product)M

KS KO



119882and 119896



119882≫ 119896

1015840


(13) takes the form

119896obs

=

119896

119882


2

(14)



1

119896obs=

1

119896

119882

+

119870S + 119870O119896

119882


Plot of 119896

minus1


4 Summary



0

02

04

06

08

1

12

14

0 5 10 15 20 25

Fructose


10minus4k

obsminus

1s


minus1


2SO4]






Acknowledgments


References























4rdquo Carbohy-





















FluidsJournal of


Journal of










Superconductivity




GravityJournal of








Journal of






Volume 2014


PhotonicsJournal of


Journal of

Biophysics






Aqueousa CTABb SDSc

10 20 05 30 080 20 062

25 111 350 086

50 155 540 123

100 20 80 163

200 264 1210 246

25 10 05 30 113 354 088

20 111 350 086

30 111 350 08540 110 350 08450 110 349 084

25 20 050 30 111 350 08610 092 260 070250 065 175 05350 049 132 039100 036 10 031

25 20 05 20 209 525 1025 182 460 09530 111 350 08640 066 230 07750 048 178 065



strength constant








rized in Table 2



log 119896obs = log 119896

1015840

0minus

119885

119860119885

119861119890

2119873

2303 (4120587120576

0) 119889

119860119861119877119879

times

1

120576

(2)

where 119896

1015840



119860and 119885


ions 119889119860119861




2in the



through NBS


NBS + H2O1198961

999444999469 HOBr + NHS (3)


0

05

1

15

2

25

0 05 1 15 2 25

aqctab

sds

5+

logk

obs

3 + log[fructose]




0

02

04

06

08

1

12

0 5 10 15 20 25 30 35 40

log[

NBS

]

aqctab

sds

t (s)



2] = 50 times








002040608

112141618

2

0 05 1 15 2 25 3

aqctab

sds

5+

logk

obs

102 1120576






0

02

04

06

08

1

12

14

16

18

0 05 1 15 2 25

aqctab

sds

5+

logk

obs

3 + log[H2SO4]










119886(kJmolminus1) 4769 4069 4827

log119901







and Δ119866







002040608

112141618

2

305 31 315 32 325 33 335

aqctab

sds

5+

logk

obs

103 1T








NBS + H2O 999445999468 NHS + HOBr (4)

HOBr + H+ 999445999468 (H2OBr)+ (5)

NBS + H+ 999445999468 (NBSH)

+ (6)

NBS + H+ 999445999468 NHS + Br+ (7)






1 119870

2are the



H

H

O


HOH2CO




O

O

O

OO

NndashBr ++ H2Ok1

kminus1NndashH HOBr


O

HOBrOH

CH2OH

+

+ +

+k2

kminus2fast

OndashBr H3O+

CH2Ominus

Fructose

O

O

O

OndashBr

CH2ndashOminus

kW

Slow


O

Brminus CH H

(7)

(12)

(13)

∙∙

∙∙

Aminus




minus

119889 [NBS]119889119905

=

119896119896

1119896


[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(8)

where

[NBS]119879


rate = 119896obs[NBS]119879 (10)

119896obs =

rate[NBS]119879

=

119896119896

1119896

2 [Fructose]

[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(11)

1

119896obs=

[H+] [NHS]119896119896

1119896

2 [Fructose]

+

[H+]119896119896

2 [Fructose]

+

1

119896

(12)






0 111 0 11102 125 02 10204 131 04 1006 150 06 09708 216 075 09310 290 08 09112 350 10 08614 240 11 08416 20 12 08118 172 14 078


119908 sminus1 (10minus4) 107 131

(119870119878+ 119870


(10minus6) 257 341


0

05

1

15

2

25

3

35

4

0 05 1 15 2

Fructose

104k

obssminus

1




2] = 50 times




0

01

02

03

04

05

06

07

08

09

1

0 5 10 15 20 25 30

Fructose


10minus4k

obsminus

1s


minus1




0

02

04

06

08

1

12

0 02 04 06 08 1 12 14 16

Fructose

104k

obssminus

1




2] = 50 times



119882path)



119896obs =

119896

119882+ 119896

1015840

119872119870S119870O (119862surf minus CMC)


(13)


119872= (119896119872

119881) 119881 is the molar


H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2OH2O

H2O

H2O

H2O

H2O

H2O

H2 O

Hydrolysis

Hydrolysis

Fructose 2HOBr

2HOBr

kW

Products

ProductskM

Brminus

Brminus Brminus

Br minusCH3

CH3

CH3

CH3

CH3

CH3

CH3

CH3

+

+

+

+

+

Fructose +

Core

Stern layer

Gouy-Chapman layer

Micellar surface

H 3CndashN

H3CndashN H3CndashN

H3 CndashN




(Product)M

KS KO



119882and 119896



119882≫ 119896

1015840


(13) takes the form

119896obs

=

119896

119882


2

(14)



1

119896obs=

1

119896

119882

+

119870S + 119870O119896

119882


Plot of 119896

minus1


4 Summary



0

02

04

06

08

1

12

14

0 5 10 15 20 25

Fructose


10minus4k

obsminus

1s


minus1


2SO4]






Acknowledgments


References























4rdquo Carbohy-





















FluidsJournal of


Journal of










Superconductivity




GravityJournal of








Journal of






Volume 2014


PhotonicsJournal of


Journal of

Biophysics




0

05

1

15

2

25

0 05 1 15 2 25

aqctab

sds

5+

logk

obs

3 + log[fructose]




0

02

04

06

08

1

12

0 5 10 15 20 25 30 35 40

log[

NBS

]

aqctab

sds

t (s)



2] = 50 times








002040608

112141618

2

0 05 1 15 2 25 3

aqctab

sds

5+

logk

obs

102 1120576






0

02

04

06

08

1

12

14

16

18

0 05 1 15 2 25

aqctab

sds

5+

logk

obs

3 + log[H2SO4]










119886(kJmolminus1) 4769 4069 4827

log119901







and Δ119866







002040608

112141618

2

305 31 315 32 325 33 335

aqctab

sds

5+

logk

obs

103 1T








NBS + H2O 999445999468 NHS + HOBr (4)

HOBr + H+ 999445999468 (H2OBr)+ (5)

NBS + H+ 999445999468 (NBSH)

+ (6)

NBS + H+ 999445999468 NHS + Br+ (7)






1 119870

2are the



H

H

O


HOH2CO




O

O

O

OO

NndashBr ++ H2Ok1

kminus1NndashH HOBr


O

HOBrOH

CH2OH

+

+ +

+k2

kminus2fast

OndashBr H3O+

CH2Ominus

Fructose

O

O

O

OndashBr

CH2ndashOminus

kW

Slow


O

Brminus CH H

(7)

(12)

(13)

∙∙

∙∙

Aminus




minus

119889 [NBS]119889119905

=

119896119896

1119896


[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(8)

where

[NBS]119879


rate = 119896obs[NBS]119879 (10)

119896obs =

rate[NBS]119879

=

119896119896

1119896

2 [Fructose]

[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(11)

1

119896obs=

[H+] [NHS]119896119896

1119896

2 [Fructose]

+

[H+]119896119896

2 [Fructose]

+

1

119896

(12)






0 111 0 11102 125 02 10204 131 04 1006 150 06 09708 216 075 09310 290 08 09112 350 10 08614 240 11 08416 20 12 08118 172 14 078


119908 sminus1 (10minus4) 107 131

(119870119878+ 119870


(10minus6) 257 341


0

05

1

15

2

25

3

35

4

0 05 1 15 2

Fructose

104k

obssminus

1




2] = 50 times




0

01

02

03

04

05

06

07

08

09

1

0 5 10 15 20 25 30

Fructose


10minus4k

obsminus

1s


minus1




0

02

04

06

08

1

12

0 02 04 06 08 1 12 14 16

Fructose

104k

obssminus

1




2] = 50 times



119882path)



119896obs =

119896

119882+ 119896

1015840

119872119870S119870O (119862surf minus CMC)


(13)


119872= (119896119872

119881) 119881 is the molar


H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2OH2O

H2O

H2O

H2O

H2O

H2O

H2 O

Hydrolysis

Hydrolysis

Fructose 2HOBr

2HOBr

kW

Products

ProductskM

Brminus

Brminus Brminus

Br minusCH3

CH3

CH3

CH3

CH3

CH3

CH3

CH3

+

+

+

+

+

Fructose +

Core

Stern layer

Gouy-Chapman layer

Micellar surface

H 3CndashN

H3CndashN H3CndashN

H3 CndashN




(Product)M

KS KO



119882and 119896



119882≫ 119896

1015840


(13) takes the form

119896obs

=

119896

119882


2

(14)



1

119896obs=

1

119896

119882

+

119870S + 119870O119896

119882


Plot of 119896

minus1


4 Summary



0

02

04

06

08

1

12

14

0 5 10 15 20 25

Fructose


10minus4k

obsminus

1s


minus1


2SO4]






Acknowledgments


References























4rdquo Carbohy-





















FluidsJournal of


Journal of










Superconductivity




GravityJournal of








Journal of






Volume 2014


PhotonicsJournal of


Journal of

Biophysics







119886(kJmolminus1) 4769 4069 4827

log119901







and Δ119866







002040608

112141618

2

305 31 315 32 325 33 335

aqctab

sds

5+

logk

obs

103 1T








NBS + H2O 999445999468 NHS + HOBr (4)

HOBr + H+ 999445999468 (H2OBr)+ (5)

NBS + H+ 999445999468 (NBSH)

+ (6)

NBS + H+ 999445999468 NHS + Br+ (7)






1 119870

2are the



H

H

O


HOH2CO




O

O

O

OO

NndashBr ++ H2Ok1

kminus1NndashH HOBr


O

HOBrOH

CH2OH

+

+ +

+k2

kminus2fast

OndashBr H3O+

CH2Ominus

Fructose

O

O

O

OndashBr

CH2ndashOminus

kW

Slow


O

Brminus CH H

(7)

(12)

(13)

∙∙

∙∙

Aminus




minus

119889 [NBS]119889119905

=

119896119896

1119896


[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(8)

where

[NBS]119879


rate = 119896obs[NBS]119879 (10)

119896obs =

rate[NBS]119879

=

119896119896

1119896

2 [Fructose]

[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(11)

1

119896obs=

[H+] [NHS]119896119896

1119896

2 [Fructose]

+

[H+]119896119896

2 [Fructose]

+

1

119896

(12)






0 111 0 11102 125 02 10204 131 04 1006 150 06 09708 216 075 09310 290 08 09112 350 10 08614 240 11 08416 20 12 08118 172 14 078


119908 sminus1 (10minus4) 107 131

(119870119878+ 119870


(10minus6) 257 341


0

05

1

15

2

25

3

35

4

0 05 1 15 2

Fructose

104k

obssminus

1




2] = 50 times




0

01

02

03

04

05

06

07

08

09

1

0 5 10 15 20 25 30

Fructose


10minus4k

obsminus

1s


minus1




0

02

04

06

08

1

12

0 02 04 06 08 1 12 14 16

Fructose

104k

obssminus

1




2] = 50 times



119882path)



119896obs =

119896

119882+ 119896

1015840

119872119870S119870O (119862surf minus CMC)


(13)


119872= (119896119872

119881) 119881 is the molar


H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2OH2O

H2O

H2O

H2O

H2O

H2O

H2 O

Hydrolysis

Hydrolysis

Fructose 2HOBr

2HOBr

kW

Products

ProductskM

Brminus

Brminus Brminus

Br minusCH3

CH3

CH3

CH3

CH3

CH3

CH3

CH3

+

+

+

+

+

Fructose +

Core

Stern layer

Gouy-Chapman layer

Micellar surface

H 3CndashN

H3CndashN H3CndashN

H3 CndashN




(Product)M

KS KO



119882and 119896



119882≫ 119896

1015840


(13) takes the form

119896obs

=

119896

119882


2

(14)



1

119896obs=

1

119896

119882

+

119870S + 119870O119896

119882


Plot of 119896

minus1


4 Summary



0

02

04

06

08

1

12

14

0 5 10 15 20 25

Fructose


10minus4k

obsminus

1s


minus1


2SO4]






Acknowledgments


References























4rdquo Carbohy-





















FluidsJournal of


Journal of










Superconductivity




GravityJournal of








Journal of






Volume 2014


PhotonicsJournal of


Journal of

Biophysics




H

H

O


HOH2CO




O

O

O

OO

NndashBr ++ H2Ok1

kminus1NndashH HOBr


O

HOBrOH

CH2OH

+

+ +

+k2

kminus2fast

OndashBr H3O+

CH2Ominus

Fructose

O

O

O

OndashBr

CH2ndashOminus

kW

Slow


O

Brminus CH H

(7)

(12)

(13)

∙∙

∙∙

Aminus




minus

119889 [NBS]119889119905

=

119896119896

1119896


[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(8)

where

[NBS]119879


rate = 119896obs[NBS]119879 (10)

119896obs =

rate[NBS]119879

=

119896119896

1119896

2 [Fructose]

[NHS] [H+] + 119896

1119896

2 [Fructose] + 119896

1[H+]

(11)

1

119896obs=

[H+] [NHS]119896119896

1119896

2 [Fructose]

+

[H+]119896119896

2 [Fructose]

+

1

119896

(12)






0 111 0 11102 125 02 10204 131 04 1006 150 06 09708 216 075 09310 290 08 09112 350 10 08614 240 11 08416 20 12 08118 172 14 078


119908 sminus1 (10minus4) 107 131

(119870119878+ 119870


(10minus6) 257 341


0

05

1

15

2

25

3

35

4

0 05 1 15 2

Fructose

104k

obssminus

1




2] = 50 times




0

01

02

03

04

05

06

07

08

09

1

0 5 10 15 20 25 30

Fructose


10minus4k

obsminus

1s


minus1




0

02

04

06

08

1

12

0 02 04 06 08 1 12 14 16

Fructose

104k

obssminus

1




2] = 50 times



119882path)



119896obs =

119896

119882+ 119896

1015840

119872119870S119870O (119862surf minus CMC)


(13)


119872= (119896119872

119881) 119881 is the molar


H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2OH2O

H2O

H2O

H2O

H2O

H2O

H2 O

Hydrolysis

Hydrolysis

Fructose 2HOBr

2HOBr

kW

Products

ProductskM

Brminus

Brminus Brminus

Br minusCH3

CH3

CH3

CH3

CH3

CH3

CH3

CH3

+

+

+

+

+

Fructose +

Core

Stern layer

Gouy-Chapman layer

Micellar surface

H 3CndashN

H3CndashN H3CndashN

H3 CndashN




(Product)M

KS KO



119882and 119896



119882≫ 119896

1015840


(13) takes the form

119896obs

=

119896

119882


2

(14)



1

119896obs=

1

119896

119882

+

119870S + 119870O119896

119882


Plot of 119896

minus1


4 Summary



0

02

04

06

08

1

12

14

0 5 10 15 20 25

Fructose


10minus4k

obsminus

1s


minus1


2SO4]






Acknowledgments


References























4rdquo Carbohy-





















FluidsJournal of


Journal of










Superconductivity




GravityJournal of








Journal of






Volume 2014


PhotonicsJournal of


Journal of

Biophysics







0 111 0 11102 125 02 10204 131 04 1006 150 06 09708 216 075 09310 290 08 09112 350 10 08614 240 11 08416 20 12 08118 172 14 078


119908 sminus1 (10minus4) 107 131

(119870119878+ 119870


(10minus6) 257 341


0

05

1

15

2

25

3

35

4

0 05 1 15 2

Fructose

104k

obssminus

1




2] = 50 times




0

01

02

03

04

05

06

07

08

09

1

0 5 10 15 20 25 30

Fructose


10minus4k

obsminus

1s


minus1




0

02

04

06

08

1

12

0 02 04 06 08 1 12 14 16

Fructose

104k

obssminus

1




2] = 50 times



119882path)



119896obs =

119896

119882+ 119896

1015840

119872119870S119870O (119862surf minus CMC)


(13)


119872= (119896119872

119881) 119881 is the molar


H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2OH2O

H2O

H2O

H2O

H2O

H2O

H2 O

Hydrolysis

Hydrolysis

Fructose 2HOBr

2HOBr

kW

Products

ProductskM

Brminus

Brminus Brminus

Br minusCH3

CH3

CH3

CH3

CH3

CH3

CH3

CH3

+

+

+

+

+

Fructose +

Core

Stern layer

Gouy-Chapman layer

Micellar surface

H 3CndashN

H3CndashN H3CndashN

H3 CndashN




(Product)M

KS KO



119882and 119896



119882≫ 119896

1015840


(13) takes the form

119896obs

=

119896

119882


2

(14)



1

119896obs=

1

119896

119882

+

119870S + 119870O119896

119882


Plot of 119896

minus1


4 Summary



0

02

04

06

08

1

12

14

0 5 10 15 20 25

Fructose


10minus4k

obsminus

1s


minus1


2SO4]






Acknowledgments


References























4rdquo Carbohy-





















FluidsJournal of


Journal of










Superconductivity




GravityJournal of








Journal of






Volume 2014


PhotonicsJournal of


Journal of

Biophysics




H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2O

H2OH2O

H2O

H2O

H2O

H2O

H2O

H2 O

Hydrolysis

Hydrolysis

Fructose 2HOBr

2HOBr

kW

Products

ProductskM

Brminus

Brminus Brminus

Br minusCH3

CH3

CH3

CH3

CH3

CH3

CH3

CH3

+

+

+

+

+

Fructose +

Core

Stern layer

Gouy-Chapman layer

Micellar surface

H 3CndashN

H3CndashN H3CndashN

H3 CndashN




(Product)M

KS KO



119882and 119896



119882≫ 119896

1015840


(13) takes the form

119896obs

=

119896

119882


2

(14)



1

119896obs=

1

119896

119882

+

119870S + 119870O119896

119882


Plot of 119896

minus1


4 Summary



0

02

04

06

08

1

12

14

0 5 10 15 20 25

Fructose


10minus4k

obsminus

1s


minus1


2SO4]






Acknowledgments


References























4rdquo Carbohy-





















FluidsJournal of


Journal of










Superconductivity




GravityJournal of








Journal of






Volume 2014


PhotonicsJournal of


Journal of

Biophysics




0

02

04

06

08

1

12

14

0 5 10 15 20 25

Fructose


10minus4k

obsminus

1s


minus1


2SO4]






Acknowledgments


References























4rdquo Carbohy-





















FluidsJournal of


Journal of










Superconductivity




GravityJournal of








Journal of






Volume 2014


PhotonicsJournal of


Journal of

Biophysics




















FluidsJournal of


Journal of










Superconductivity




GravityJournal of








Journal of






Volume 2014


PhotonicsJournal of


Journal of

Biophysics



Research Article Kinetic Treatment of the Reaction of...

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Transcript of Research Article Kinetic Treatment of the Reaction of...