Kinetics and Mass Transfer of Free Fatty Acids Esterificatio(9)

r*)observedreactionrateperunitofparticlesvolume(mol/(mincm3))

Wcat)catalystweight(g)

XOA)fractionalconversionofoleicacid

Ain,Aout)acidity(%bywt)oftheinletandoutletstreams(wt%)

Qtot)overallvolumetricfeedflowrate(cm3/min)L)bedlength(cm)DR)beddiameter(cm)Rp)particleradius(cm)

xi)liquidphasemolefractionofcomponentiφi)associationfactorforcomponentiT)absolutetemperature(K)µ)viscosity(g/(cmmin))

Vi)molarvolumeofcomponenti(cm3/mol)W)weightofcatalystloadedinthereactor(g)η)catalysteffectivenessfactor

Vi)stoichiometriccoefficientofcomponentiMw)i)molecularweightofcomponenti(g/mol)C0concentrationattheparticlesurface(mol/cm3)

CiS)concentrationofcomponentiattheparticlesurface(mol/cm3)

Ci)concentrationofcomponenti(mol/cm3)z)reactoraxialcoordinate(cm)as)specificsurfacearea(cm2/cm3)JS,i)mass-transferrate(mol/(mincm2))U)linearvelocity(cm/min)

Deff)effectivediffusivity(cm2/min)Deff,B)effectivediffusivity(cm2/min)

D,DA,Mix)moleculardiffusivityofcomponentAinmixture(cm2/min)

p)particleporosity B)bedporosity

Fcat)catalystdensity(g/cm3)

σ)constrictionfactor(particleorbed)τP)intraparticletortuosityfactorτB)bedtortuosityfactor

ks,ksi)externalmass-transfercoefficient(cm/min)Sh)SherwooddimensionlessnumberSc)SchmidtdimensionlessnumberRe)Reynoldsdimensionlessnumber

Roil/MeOHIN)volumetricratioofacidicoiltomethanolinthefeed

xA)molefractionofoleicacidinthereactionmixturexM)molefractionofmethanolinthereactionmixturexE)molefractionofmethyloleateinthereactionmixturexW)molefractionofwaterinthereactionmixture

Ind.Eng.Chem.Res.,Vol.46,No.15,20075121

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ReceiVedforreViewDecember20,2006ReVisedmanuscriptreceiVedMay7,2007

AcceptedMay15,2007

IE061642J