Contoh Soal dan Jawaban Teknik Reaksi Kimia

Ujian Tengah Tengah Semester : Mata Uji Dosen Pe Pembina Hari/Tanggal 'akt Si*at

: Teknik Reaksi Kimia 3 : Ir Ir. Mi Mining Ha Harsanti MS MSc. : Mingg/!" #$ril %&!& : !%& menit (% jam) : +ka +k

 ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,   ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, ,,,,,,,,,,,,,,,,,,,,,,,,, 

Soal 1 (nilai 50) 'e are consi-ering getting something o* ale *rom aste stream o* a $rocess. This stream (%&&&& liters/-a0) contains chemical # (&.&! kg/liter) hich can be h0-rol01ein a2eos soltion to gie chemical R (ale  4!.&&/kg trans*orme-). Pro-ct R can  be recoere- *rom the soltion at negligible cost hile nreacte- # goes to aste. 5rom the in*ormation belo calclate calclate the 1ise o* Mi6e- Reactor an- conersion leel hich ill ma6imi1e a) the $ro*it  b) the rate o* retrn on inestment ine stment

Data : 7n an ann annal al basi basiss the the cost cost o* reac reacto torr anan- s$$ s$$or orti ting ng e2i e2i$m $men ent8 t8 incl incl-in ing g -e$reciation an- interest charges is : 4m  4%%9 !/% 8 olme in liters ;abor an- o$erating cost  4%&/o$erating -a08 3&& o$erating -a0/0ear. The h0-rol0sis reaction is *irst or-er ith res$ect to # ith a rate constant k  &.%9/hor. Penyelesaian  : reaksi *asa cair : 

 ja-i : 

 

R  

 &  = #  = #& (! < 6 # )

+erlangsng -i -alam Mi6e- Reactor : :=STR   5#&



#

6# 6  = #& . & # < r # < r #

Reaksi or-e>sat terha-a$ # -engan k  &8%9/jam  r   k = #  k = #& (! < 6 # )  A



:=STR   5#&

&8%9 = #& (! < 6 # )  jam

6# 6  = #& . & # < r # < r #

:=STR   =#& . &

6# &8%9  jam

= #& (! < 6 # )

:=STR   . &

6# &8%9 (! < 6 # )  jam

:=STR   %& &&&

:=STR  





6#

!& &&& 3

liter 

(! < 6 # )

+ia0a ntk reactor berikt $eraatan -an $eralatan $en-kngn0a serta -e$resiasi $er tahn : SM  4 %%9 :!/%



6# liter  ! hari hari %?  jam &8%9 (! < 6 # )  jam

@

: -alam liter 

+ia0a brh 4%&/hari@ ! tahn  3&& hari kerja = #&  &8&! kg/liter 



Pro-k R 0ang -ihasilkan : = R   = #&  6 #



Untk laj alir olmetric : . &  %& &&& liter/hari 1at # -alam aliran m$an  &8&!



Untk ! tahn $ro-ksi : R  0ang -ihasilkan  %&& 6 #



4!8& kg

kg tahn



4A& &&& 6 # tahn

4%%9 tahn

!/ %

!/%

:

 !& &&&   4%%9     3  

+ia0a ntk brh $er tahn : +ia0a ntk brh 



B A& &&& 6 #

+ia0a ntk reactor $ertahn : +ia0a ntk reaktor 



kg 3&& hari kg  A& &&& 6 # hari tahn tahn

Harga jal $ro-k R : Sale $ro-k R 



kg liter  kg %& &&&  %&& liter  hari hari

4%& 3&& hari  4A&&&/tahn hari tahn

Pro*it ata kentngan $ertahn : Pro*it  harga $ro-k <  bia0a $ro-ksi

!/%

  6 #      ! < 6 #  

!/%

P  4 A& &&& 6 #



 !& &&&  < 4 %%9     3  

!/%

  6 #     ! <  6 #    

< 4 A&&&

P  *  (6 # ) -P  & -6 #

Pro*it maksimm jika :

!/%

 !& &&&  < %%9     3  

P  A& &&& 6 #

-P -6 #

!/%

 !& &&&   A& &&& < %%9     3   !/%

 !& &&&  A& &&& < %%9     3   !/%

  6 #    -  ! < 6 #    

 -

!/%

  6 #    -  ! < 6 #    



!/%

  6 #    -  ! < 6 #    





!/%

  6 #    -  ! < 6 #    



!/%

  6 #    -   ! < 6 #  



< A&&&

!/%

  6 #    -   ! < 6 #  

< &

!/%

  6 #    -   ! < 6 #  

6 !/% # (! < 6 # )! / %



 &

!/ % (! < 6 # )! / % -(6 # )! / % <  6 !/% # - (! < 6 # )

(! < 6 # ) % / %


(! < 6 # ) % / % !/% (6 # ) < ! / % (! < 6 # )!/ % (! < 6 # ) % / %

!/%

  6 #    -   ! < 6 #  

!/%

  6 #      ! < 6 #  

! % (6 # ) ! / % (! < 6 # )! / %

(! < 6 # ) % / % % (6 # ) ! / % (! < 6 # ) 3 / %

(! < 6 # ) % (6 # )

!/ %

(! < 6 # )

3/ %

<

<

<

<

!/% (6 # ) ! / % (! < 6 # ) < ! / % (! < 6 # ) % / %

(6 # ) ! / % % (! < 6 # ) 3 / %

(6 # ) !/ % (6 # ) ! / % % (6 # ) ! / % (! < 6 # ) 3 / %

6# % (6 # )

!/ %

(! < 6 # ) 3 / %

!/%

  6 #    -   ! < 6 #  

(! < 6 # ) < 6 #



% (6 # ) ! / % (! < 6 # ) 3 / %

!/%

  6 #    -  ! < 6 #    

!



% (6 # )

!/ %

(! < 6 # ) 3 / %

!/%

 !& &&&  A& &&& < %%9     3  

!/%

  6 #    -  ! < 6 #    

!/%

 !& &&&  A& &&& < %%9     3  

! % (6 # ) ! / % (! < 6 # ) 3 / %

!/%

 !& &&&  A& &&&  %%9     3  

(6 # )

!/ %

(6 # )

!/ %

(! < 6 # )

3/ %

(! < 6 # )

3/ %

(6 # ) (! < 6 # )

3



 &

! % (6 # )

!/ %

(! < 6 # ) 3 / %

%%9  !& &&&      % (A& &&&)   3  

!/%

(3) (C9)  !& &&&      % ("&&) (C9)   3  

(3) % (!A&&)

%

 &

!/%

 !& &&&      3  

(6 # ) (! < 3 6 #  3 6 %# <  6 3# ) 

(6 # ) (! < 3 6 #  3 6 %# <  6 3# ) 

3& &&& (!A) % (!& &&&)

3 (%9A)

%9A (6 # ) (! < 3 6 #  3 6 %# <  6 3# )  3 %9A  6 ?# < 3 (%9A) 6 3#  3 (%9A) 6 %# < %9A 6 #  3  &

Di-a$at : 6#   &8C9

a.

6#

:=STR  

!& &&& 3

(! < 6 # )

:=STR  

!& &&&

&8C9

3

liter 



(! < &8C9)

!& &&&

3  !& &&& liter 

3

 b. Rate o* Retrn on Inesment (R7I) R7I 

 $ro*it $er tahn  6 !&&D total in.esment !/%

P  4 A& &&& 6 #

 !& &&&  < 4 %%9     3  

!/%

  6 #     ! <  6 #     !/%

 !& &&&  P  4 A& &&& (&8C9) < 4 %%9     3  

< 4 A&&&

!/%

  &8C9      ! < &8C9 

P  4 A& &&& (&8C9) < 4 %% 9&& < 4 A &&&  4 !A 9&&

!/%

 !& &&&  In.estasi  4 %%9     3  

 4 %% 9&&  4 A &&&  4 %" 9&&

R7I 

!/%

  &8C9     ! < &8C9    

4 !A 9&&  6 !&&D  9"D 4 %" 9&&

 4 A&&&

< 4 A&&&

Soal 2 (nilai 50) Reaksi *asa cair : # E + P a-alah reaksi searah -an elementer 8 berlangsng -i-alam reactor alir -engan m$an 1at # -an 1at + $a-a jmlah 0ang e2imolar $a-a tem$eratre %C o= -an laj alir  olmetric sebesar % liter/-etik. a) a$abila reaksi berlangsng secara a-iabatik8 hitng olme =STR 0ang -i$erlkan ntk menca$ai konersi sebesar FF.  b) hitng tem$eratre m$an mask maksimm8 s$a0a tem$eratre reaksi (0ait titik -i-ih cairan reaksi) ti-ak boleh melebihi 99& K sekali$n ntk konersi sem$rna. Diketahi : Panas $embentkan : H#o ($a-a %C3 K)  < %& kcal/mol. H+o ($a-a %C3 K)  < !9 kcal/mol. HPo ($a-a %C3 K)  < ?! kcal/mol. Konsentrasi aal #  =#&  &8! mol/liter  Ka$asitas $anas (=$) =$#  =$+  !9 cal/(mol K) =$P  3& cal/(mol K) Konstanta laj reaksi (k) $a-a tem$eratre 3&& K a-alah &8&! liter/(mol -etik) Gnergi aktiasi  G  !& &&& cal/mol.

Pen0elesaian : B) Reaksi *asa cair berarti reaksi ti-ak mengalami $erbahan olme *li-a ata $erbahan laj alir olmetric (  &) B) = #  = #& (! < 6 # ) B) reaksi elementer : < r #  k = # = + B) -ignakan m$an $a-a jmlah e2imolar8 berarti : n #&  n +& 0 #&  0 +&  !/% B) -ari $ersamaan stokiometri reaksi : = #  =+ % % % B) ja-i $ersamaan laj reaksi menja-i : < r #  k = #  k = #& (! < 6 # )

B) reaksi berlangsng -i -alam =STR :

:=STR   5#&

6# 6  =#& .& # < r # < r #

6#

:=STR   =#& .&

k =%#& (! < 6 # )%

&8FF k (&8!) (! < &8FF) %

:=STR   %

!8F" k (&8!) (&8&!)%

:=STR  

(!8F") (!&) (!&&&&) (!8F") (!&)9  :=STR   k k

Konstanta laj reaksi (k) $a-a tem$eratre 3&& K a-alah &8&! liter/(mol -etik) Gnergi aktiasi  G  !& &&& cal/mol. k  #e

<

G RT

B) Mencari/menghitng nilai k $a-a tem$eratre T B) menghitng tem$eratre T $a-a konersi sebesar 6#  &8FF

T 

in



6  <  H (TR )  o R 

 i

= $ i T&  6  = $ TR 

i !

in

  = $ i

i

  6  = $

i !

 H oR (TR )   H o*8 P (TR ) <  H o*8 # (TR ) <  H o*8 + (TR )

 H oR (TR )  < ?!  %&  !9  < A kkal/mol  < A&&& kal/mol in

  = $ i

i

 ( # = $ # 

 +

= $ +   P = $ P )

i !

in

 

i

= $ i  (! B!9  ! B !9  & B 3&)  3&

i !

= $  =$ P < =$ # < =$ +  3& < !9 < !9  &

&8FF (< (
T 

<

e

k ?F" K  

<

e <

!&&&&

<

(!8F")(?F" )

k 3&& K  

!&&&& (!8F"C)(3& &)

G RT

<

e <

e

G R(?F")

<

!&&&& (!8F")(?F" ) !&&&&

(&8&!) 

(!8F"C)(3& &)

G !8F"C(?F")

k ?F" K  #e e e     G G G < < < k 3&& K  # e RT e R(3&&) e !8F"C(3&&) a. Menghitng olme reactor ntk menca$ai konersi sebesar FF

(!8F") (!&) (!&&&&) (!8F") (!&)9 :=STR    k k



 b. Menentkan tem$eratre m$an s$a0a tem$eratre reaksi -i -alam reactor  ti-ak lebih -ari 99& K 

99& 

in



6  <  H (TR )  o R 

 i

= $i T&  6  = $ TR 

i !

in

  = $ i

i

  6  = $

i !

99&  99& 

!8& (< (
!A9&&  A&&&  3& T& !&9&&  3& T&  T&  39& K