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ContentsContents

Fundamentals of AdsorptionFundamentals of Adsorption

Adsorbent propertiesAdsorbent properties

Adsorber designAdsorber design

ThermodynamicsThermodynamics

KineticsKineticsIndustrial applicationsIndustrial applications

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Fundamentals ofFundamentals of

AdsorptionAdsorption

Surface phenomenon: unlikeSurface phenomenon: unlikeabsorption which is bulkabsorption which is bulkphenomenonphenomenon

i!usion of moleculesi!usion of molecules "seful in remo#ing trace components"seful in remo#ing trace components "sed to reco#er compounds or get"sed to reco#er compounds or get

rid of no$ious substancerid of no$ious substance

%rinciple%rinciple istillation: &olatilityistillation: &olatility

'$traction: istribution coe!cient'$traction: istribution coe!cient

Absorption: SolubilityAbsorption: Solubility

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Some common termsSome common terms

%hysical adsorption (%hysical adsorption (ChemisorptionChemisorption

Adsorption is alwaysAdsorption is always

')*T+',-IC')*T+',-IC -onolayer.-ultilayer adsorption-onolayer.-ultilayer adsorption

Fi$ed bed adsorberFi$ed bed adsorber

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Adsorbent propertiesAdsorbent properties

/arge internal surface area/arge internal surface area %ore si0e distribution%ore si0e distribution

'asily regenerated'asily regenerated Should not age rapidly with timeShould not age rapidly with time -echanically strong enough to-echanically strong enough to

withstand bulk handling andwithstand bulk handling and

#ibrations#ibrations Some e$amples:Some e$amples:

-olecular sie#es1 Acti#ated carbon1-olecular sie#es1 Acti#ated carbon1

Silica gel1 Acti#ated AluminaSilica gel1 Acti#ated Alumina

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Adsorber designAdsorber design

Thermodynamics: Adsorption e2uilibriumThermodynamics: Adsorption e2uilibrium/angmuir Isotherm/angmuir Isotherm3'T Isotherm3'T Isotherm

4ibbs Isotherm4ibbs Isotherm

Adsorption kineticsAdsorption kineticsetermines e!iciency of real processetermines e!iciency of real process+eat ( -ass transfer limitations+eat ( -ass transfer limitations

,eaction kinetics limitations,eaction kinetics limitations-i$ing ( i!usion in the inter.particle #oid space-i$ing ( i!usion in the inter.particle #oid space

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Transport -echanismsTransport -echanisms

Inter.particle transport mechanismsInter.particle transport mechanisms %ore di!usion: -acropore di!usion%ore di!usion: -acropore di!usion

Solid di!usion: Surface di!usion orSolid di!usion: Surface di!usion ormicro.pore di!usionmicro.pore di!usion

,eaction kinetics at phase boundaries,eaction kinetics at phase boundaries

'$tra.particle transport mechanisms'$tra.particle transport mechanisms '$ternal mass transfer'$ternal mass transfer

-i$ing-i$ing

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Transport -echanismsTransport -echanisms

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Inside the adsorbent5Inside the adsorbent5

Local EquilibriumBetween Fluid Phase

and Adsorbent Phase

Pore

Diffusion

Surface

Diffusion

R

r+r

r

Bulk

Solution

Linear

Drivin

Force

Boundar!

La!er

r

"b

"s

qr

"#$r

Fluid Phase Adsorbent Phase

%ass

Flu&

%ass

Flu&

r

= k C Cf b s = D q

r

D C

rs a

r l p

p

p r

$

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Industrial applicationsIndustrial applications

&6778: Cracked gas drier: -olecular sie#es&6778: Cracked gas drier: -olecular sie#es

%SA: %ressure Swing Adsorption: Alcohols plant%SA: %ressure Swing Adsorption: Alcohols plant

Ion e$change bed: emin water plantIon e$change bed: emin water plant I%A *dor remo#al: Sol#ents plantI%A *dor remo#al: Sol#ents plant

ehumidi9cation of air esiccant;: Air.sepehumidi9cation of air esiccant;: Air.sepplantplant

/argest application in laboratories/argest application in laboratories ChromatographChromatograph

4el permeation techni2ue4el permeation techni2ue

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Contents co#eredContents co#ered

Fundamentals of AdsorptionFundamentals of Adsorption

Adsorbent propertiesAdsorbent properties

Adsorber designAdsorber designThermodynamicsThermodynamics

KineticsKineticsIndustrial applicationsIndustrial applications

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