ice 204 chp1 introduction
TRANSCRIPT
ICE 204 – KINETIKA & KATALISIS
I. PENDAHULUAN
I.1 Teknik reaksi kimia (kinetika, katalisis, dan
perancangan reaktor) sebagai salah satu inti
ilmu TK
I.2 Kinetika reaksi kimia
I.3 Katalisis
II. TERMODINAMIKA REAKSI KIMIA
II.1 Kesetimbangan reaksi kimia
II.2 Kespontanan reaksi
II.3 Pengaruh kondisi reaksi (T,P) terhadap
kesetimbangan
II.4 Konversi maksimum (kesetimbangan)
III. KINETIKA REAKSI HOMOGEN TANPA KATALIS
III.1 Laju, orde, konstanta laju, dan mekanisme
reaksi kimia
III.2 Pengaruh T terhadap laju reaksi
III.3 Laju reaksi sederhana : reaksi satu arah
dengan reaktan tunggal dan jamak
III.4 Reaksi bolak-balik
III.5 Reaksi kompleks : seri, paralel, dan seri-
paralel
IV. PERCOBAAN DAN ANALISIS DATA
IV.1 Aspek-aspek eksperimen kinetika reaksi
IV.2 Metode interpretasi data kinetika
IV.3 Metode diferensial
IV.4 Metode integral
V. KATALIS & KATALISIS
V.1 Katalis & katalisis dalam reaksi kimia
V.2 Klasifikasi katalis
V.3 Katalis homogen dan heterogen
VI. KATALISIS DALAM INDUSTRI
VI.1 Katalis dalam industri
VI.2 Katalis padat
VI.3 Katalis industri homogen
VI.4 Katalis industri heterogen
VI.5 Paper project :
A. Katalisis dalam kilang minyak dan
industri petrokimia: Hydrotreating,
Gasoline production, Olefins
B. Katalisis dalam produksi amoniak
VII. KINETIKA REAKSI BERKATALIS HOMOGEN
VIII. KINETIKA REAKSI BERKATALIS HETEROGEN
NOTES:
1. JUMLAH MINGGU PERKULIAHAN = 13 - 14
2. ABSENSI MINIMUM (SYARAT WD 1) = 80%
3. PERKIRAAN BOBOT PENILAIAN :
QUIZ / TUGAS = 20%
UTS = 40%
UAS = 40%
4. BUKU PEGANGAN :
i. Ronald W. Missen, Charles A, Mims, & Bradley A. Saville.
Introduction to Chemical Reaction Engineering & Kinetics. John
Wiley & Sons, 1999 – CD
ii. J. M. Smith. Chemical Engineering Kinetics. 3rd Edition, Mc-
Graw-Hill, 1981
iii. Charles G. Hill Jr. An Introduction to Chemical Engineering
Kinetics & Reactor Design, John Wiley & Sons, 1977
5. BUKU RUJUKAN / PELENGKAP :
i. I. Chorkendorff, J.W. Niemantsverdriet. Concepts of Modern
Catalysis and Kinetics. 2nd Edition, Wiley-VCH, 2007 – CD
ii. Jens Hagen. Industrial Catalysis. 2nd Edition, Wiley-VCH, 2006
iii. Nicolas P. Chopey. Handbook of Chemical Engineering
Calculations. 3rd Edition, Chapter 5 Reaction Kinetics & Reactor
Design – CD
iv. Robert H. Perry. Handbook of Chemical Engineers. 7th Edition,
Section 7 Reaction Kinetics – CD
v. Margaret Robson Wright. An Introduction to Chemical Kinetics.
John Wiley & Sons, 2004 – CD
6. e-Learning : http://elearning.unpar.ac.id berisi
slide2 kuliah, tugas, pengumuman, dll. Diupdate
tiap minggu. Enrolment key & sign up!
ICE 204 KINETIKA & KATALISIS – CHAPTER 1
CHP 1 - INTRODUCTION
This section covers the definition of chemical kinetics and
catalysis and their linkage with other core chemical
engineering courses
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ICE 204 KINETIKA & KATALISIS – CHAPTER 1
1.1 Chemical kinetics is the study of the rate
and mechanism by which one chemical
species is converted to another.
Rate [=] mass (moles) of a reactant consumed or a
product produced per unit time (rate is normally per
unit volume of reaction mixture – homogeneous
reactions OR per unit mass of catalyst –
heterogeneous fluid-solid reactions).
Mechanism is the sequence of individual chemical
events whose overall-result produces the observed
reactions.
2 NO + 2 H2 N2 + 2 H2O
the steps of reaction :
2 NO + H2 N2 + H2O2
H2O2 + H2 2 H2O
However, to design a reactor the reaction
mechanism is NOT necessary.
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ICE 204 KINETIKA & KATALISIS – CHAPTER 1
1.2 Catalysis is all processes in which the
rate of a reaction is influenced by a
substance that remains chemically
unchanged. The catalysis material does
take part in the reaction, however, it
remains unchanged at the end of the
reaction.
Source : Concepts of Modern Catalysis and Kinetics
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ICE 204 KINETIKA & KATALISIS – CHAPTER 1
Why catalysts are VERY important? (Concepts of
Modern Catalysis and Kinetics)
• around 90% industrial reactions use catalysts
• catalysts make reactions proceed much faster and
milder conditions (lower T & P) can be used
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ICE 204 KINETIKA & KATALISIS – CHAPTER 1
• catalysts direct and control reactions: speed up the
desirable reaction and at the same time slow down
unwanted reactions.
PBA →+ (desirable)
QA → (side reaction)
for reactions without any catalysts presence: choose a correct
type of reactor and/or reaction conditions so that rP >> rQ.
most of industrial reactions are catalytic; directing reaction to
be selective for main product is one of the main features of a
catalyst!! Therefore, a proper or suitable catalyst needs to be
designed and used for a specific reaction.
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ICE 204 KINETIKA & KATALISIS – CHAPTER 1
Source : Fogler, Elements of Chemical Reaction Engineering
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ICE 204 KINETIKA & KATALISIS – CHAPTER 1
1.3 Tasks to be addressed by a chemical
engineer regarding chemical reactions:
A. Determine whether a reaction is thermodynamically
and economically feasible – a reaction may be either
thermodynamically possible (ΔG < 0) OR not (ΔG > 0)
at a certain condition (P, T). In addition, ΔGo (Po = 1
atm) may be the first indication of economical
feasibility of a reaction. ΔGo is also useful for
predicting the maximum (equilibrium) conversion.
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ICE 204 KINETIKA & KATALISIS – CHAPTER 1
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B. Design reactor type and dimension – space time
(how long the reaction mixture should be placed or
flowing inside the reactor).
C. Determine reactor construction-materials – reaction
mixture nature and conditions (P, T).
Source : Subagyo, Slide Kuliah “Kinetika & Katalisis “ – Reaktor-reaktor Industrial
ICE 204 KINETIKA & KATALISIS – CHAPTER 1
TTHHEERRMMOODDYYNNAAMMIICCSS
TTRRAANNSSPPOORRTT PPHHEENNOOMMEENNAA
spontaneous
((mmaassss,, eenneerrggyy,, mmoommeennttuumm))
CCHHEEMMIICCAALL KKIINNEETTIICCSS
kinetic exp: intrinsic kinetic
CCHHEEMMIICCAALL RREEAACCTTOORR DDEESSIIGGNN
X max
Intrinsic kinetics Space time
Catalytic aspects (selectivity, deactivation,
amount) Δ H (+ / -)
Scale up Heterogeneous-
catalytic reactions
Other Chem Eng CORE subjects: Mass & energy balances Separation processes (OTK III
& IV) Fluid mechanics (OTK I) Heat transfer (OTK II)
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ICE 204 KINETIKA & KATALISIS – CHAPTER 1
Intrinsic kinetic means the chemical species change rates
are ONLY dependent on the chemical transformation
process and not affected by other (possible & influencing)
physical effects.
Reliable correlations for most mass and energy transfer
are usually available, however, intrinsic kinetics are
ALWAYS obtained from experiments.
Possible influencing physical effects: mass transfer
limitations (diffusion), the degree of mixing, non-
isothermallity. In a catalytic heterogeneous reaction, the
intrinsic kinetic determination is a rather complex
problem, because the rate of physical (diffusion) effects
must be minimized and much smaller than the reaction.
Therefore, to minimize these physical effects, intrinsic
kinetic determinations are normally carried out in a small
laboratory scale reactors (either batch or continuous).
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ICE 204 KINETIKA & KATALISIS – CHAPTER 1
1.4 SCALE-UP COMMERCIAL REACTORS (Smith, Chemical Eng Kinetics)
LAB SCALE REACTORS
LLAARRGGEE SSCCAALLEE IINNDDUUSSTTRRIIAALL RREEAACCTTOORRSS
PPIILLOOTT SSCCAALLEE RREEAACCTTOORRSS
Intrinsic rate
intrinsic rate +
influence of the physical
steps (depends on the reactor type chosen) Significance of
physical processes is minimized
Operated at near isothermal
1) Physical resistances are directly projected to a large reactor unit
2) The large reactor should have the same inter-relationship of chemical & physical process > reactor dimensions & operating conditions must be similar as in the pilot scale reactor
3) Scale-up will be easier if exactly the same type of reactor is used for lab & commercial applications – pilot scale may be omitted unless an integrated pilot plant is necessary to build
4) 3 types of diffusional effects need to be considered for scaling up heterogeneous reactors (eg. fixed bed reactor): mixing characteristics, cohesion between the fluid (gas or liquid) and solid catalyst, internal diffusion
Miniature of REAL industrial reactors
Particular reactor type is chosen
Operating conditions are chosen
Economic considerations
Hardly isothermal
SCALE-UP – see the illustration at next page
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