Ice 204 Chp1 Introduction

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ICE 204 KINETIKA & KATALISISI. 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 seriparalel

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. JohnWiley & Sons, 1999 CD ii. iii. J. M. Smith. Chemical Engineering Kinetics. 3rd Edition, McGraw-Hill, 1981 Charles G. Hill Jr. An Introduction to Chemical Engineering

Kinetics & Reactor Design, John Wiley & Sons, 1977

5. BUKU RUJUKAN / PELENGKAP :i. ii. iii. I. Chorkendorff, J.W. Niemantsverdriet. Concepts of Modern

Catalysis and Kinetics. 2nd Edition, Wiley-VCH, 2007 CDJens Hagen. Industrial Catalysis. 2nd Edition, Wiley-VCH, 2006 Nicolas P. Chopey. Handbook of Chemical Engineering

Calculations. 3rd Edition, Chapter 5 Reaction Kinetics & ReactorDesign CD iv. v. Robert H. Perry. Handbook of Chemical Engineers. 7th Edition, Section 7 Reaction Kinetics CD 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 - INTRODUCTIONThis 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 H 2O

the steps of reaction : 2 NO H2O2 + + H2 H2 N2 + H2O2

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 ofModern 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.A + B P A Q(desirable) (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 (G < 0) OR not (G > 0) at a certain condition (P, T). In addition, Go (Po = 1 atm) may be the first indication of economical feasibility of a reaction. Go is also useful for predicting the maximum (equilibrium) conversion.

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ICE 204 KINETIKA & KATALISIS CHAPTER 1

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

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ICE 204 KINETIKA & KATALISIS CHAPTER 1 kinetic exp:intrinsic kinetic

spontaneous

THERMODYNAMICSX max

CHEMICAL KINETICS

TRANSPORT PHENOMENA (mass, energy, momentum)

H (+ / -)

Intrinsic kinetics Space time Catalytic aspects (selectivity, deactivation, amount)

Scale up Heterogeneouscatalytic reactions

CHEMICAL REACTOR DESIGN

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, nonisothermallity. 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 REACTORSIntrinsic rate

PILOT SCALE REACTORS

intrinsic rate

+influence of the physical steps (depends on the reactor type chosen)

LARGE SCALE INDUSTRIAL REACTORS

Significance of physical processes is minimized Operated at near isothermal

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 1) Physical resistances are directly projected to a large reactor unit 2) The large reactor should have the same interrelationship 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

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ICE 204 KINETIKA & KATALISIS CHAPTER 1

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