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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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11

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11

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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 simpli@ed 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