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mechanism of catalyst deactivation

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    Deactivation of catalystduring steam reforming of

    Model Bio-OilPresented by:Hemlata Malav

    Priyanka GuptaSanana MandraiS!ubam Gupta"inita #umari

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    Steam reforming over variouscatalyst

    $ioc!e %&' #ulkarni S&' Meunier (& %&' Breen )& P&' Burc! $& '*Steam reforming of modelcompounds and fast pyrolysis bio-oil on supported noble metal catalysts*' +pplied%atalysis B: ,nvironmental . /01123 .415.46

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    7n absence of catalyst t!e maor products 8ere %O0and %H9 8it! only minor fractions of %O and H0& !ee;tent of t!e reaction increased 8it! temperature and

    at

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    Possible reactions

    %H4%OOH 0 H0O F %O0 9H0 /.4.&9

    kmol3

    0%H4%OOH F %H4%O%H4 %O0 H0O

    /-.2&.kmol3

    %O H0O F %O0 H0 /-9.#)mol3

    %O4H0F%H9 %O0/-01&.#)mol3

    %O0 9H0F %H9 0H0O /-.2&.#)mol3 %H4%OOH F 0%O0H0 /0.4&9#)mol3

    %H9 H0O F%O4H0/01 #)mol3

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    . 0 4 9 2 < C 612

    .1

    .2

    0102

    41

    42

    9192

    21

    H0 yield

    H0 selctivity

    s/c ratio

    yield,selectivity

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    %atalyst Deactivation

    %atalyst deactivation during steamreforming of

    acetic acid over PtArO0

    0%H4%OOH F %H4%O%H4 %O0 H0O

    0%H4%O%H4F /%H430%/OH3%H0%O%H4

    /diacetonealco!ol3 F /%H430%%H%O%H4/mesityl

    o;ide3 H0O

    /%H430%%H%O%H4

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    /%H430%%H%O%H4

    F/%H43%%H0/isobutene3 F

    %0'%4/oligomers3 %H4%OOH F %H0%O H0O/ketene

    formation3

    0%H0%O F %0H9 0%O 0%H0%O F %4H9 %O0

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    #a>u!iro akanabe' #en-ic!i +ika' #& Ses!an' Ieon IeJerts' %atalyst deactivation duringsteam reforming of acetic acid over PtArO0' %!emical ,ngineering )ournal' "olume .01'7ssues .50' . )uly 011' Pages .44-.4

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    Deactivation model

    !e kinetics of bot! t!e main reaction andt!e coking reactions are intimatelyconnected

    !e monolayer5multilayer coke gro8t!model is used to describe t!e cokeformation kinetics

    %oke content in t!e catalyst is describedby taking into account a simultaneousformation of coke over t!e surface of t!ecatalyst and a multilayer coke deposition

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    otal coke formation

    Monolayer

    Multilayer

    % is t!e total coke concentration at any time%m coke concentration in monolayer%M ' multi-layer%ma; ma;imum coke concentration in monolayerk. and k0 are rate constants given by +rr!enius

    e;pression!' n' m are constant

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    !e eLuations 8ere solved for diJerentcombinations of !'n'mN&

    !e @nal values obtained from best @t 8ere!.' n . and m 1&(or t!ese values of !' n and m' t!e above setof eLuations 8ere [email protected] into follo8ingeLuations after integration

    "& +gar8al' Sanay Patel' #& Pant' H0 production by steam reforming of met!anol over

    %uAnO+l0O4 catalysts: transient deactivation kinetics modeling' +pplied %atalysis +:General "olume 0

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