CCB 4433Reactor Design for Petrochemicals

2015 September Semester

Lecturer:

Associate Prof Dr Suzana Yusup

Department of Chemical Engineering

Course Contents & DeliveryIntroduction and fundamental of catalyst 5 hrs

Importance of catalyst and catalyst technologyIntroduction to homogeneous and heterogeneous catalysis and system

Fundamental of catalytic technology 5 hrsAdsorption isothermsCatalysisApplication of catalyst for petrochemical processes

Catalyst materials 4 hrsStructurePreparation and forming of catalyst

Catalyst characterization 4 hrsEntire catalystMetal on support

Heterogeneous catalytic reaction 6 hrsReaction kineticsPore diffusion resistancePerformance equation for reactors with heterogeneous catalyst

Fluid-particle reaction 6 hrsIntroduction of modelsShrinking-core modelShrinking-particle modelProgressive conversion model

Catalytic reactor system 6 hrsGas-solid catalyst reactorFluidized bed

References

1. Fogler H. S., Elements of Chemical Reaction Engineering, 3rd Ed., Prentice Hall, 1999.

2. Levenspiel O., Chemical Reaction Engineering, 3rd Ed., John Wiley, 1999.

3. Froment G. F. and Bischoff K. B., Chemical Reactor Analysis and Design, 2nd Ed., John Wiley, 1990.

4. C. H. Bertholomew et al., Fundamentals of Industrial Catalytic Processes 2nd ed., Wiley Interscience (2006).

Chemical Engineering Programme Outcomes (12POs)

• Apply knowledge of mathematics, science and engineering fundamentals and an engineering specialisation to the solution of complex chemical engineering problems.

• Identify, formulate, research literature and analyse complex chemical engineering problems reaching substantiated conclusions using first principles of mathematics, natural sciences and engineering sciences

• Design solutions for complex chemical engineering problems and design systems, components or processes that meet specified needs with appropriate consideration for public health and safety, cultural, societal, and environmental considerations. (PO3)

• Investigate complex chemical engineering problems using research based knowledge and research methods including design of experiments, analysis and interpretation of data and synthesis of information to provide valid conclusions. (PO4)

• Use modern engineering and IT tools to evaluate complex chemical engineering activities.• Apply reasoning informed by contextual knowledge to assess societal, health, safety, legal and cultural issues and the

consequent responsibilities relevant to professional engineering practice.• Understand the impact of professional engineering solutions in societal and environmental contexts and demonstrate

knowledge of and need for sustainable development.• Apply ethical principles and commit to professional ethics and responsibilities and norms of chemical engineering

practice• Communicate effectively on complex chemical engineering activities with the engineering community and society.• Function effectively as an individual, and as a member or leader in diverse teams and in multi-disciplinary settings.• Recognise the need for, and have the preparation and ability to engage in independent and life-long learning in the

broadest context of technological change.• Demonstrate knowledge and understanding of engineering and management principles and apply these to one’s own

work, as a member and leader in a team, to manage projects and in multidisciplinary environments.

Course Learning Outcomes (5CLOs)

At the end of this course, students should be able to:CLO1. Understand and appreciate catalysis and catalyst for designing solutions for complex chemical engineering problemsCLO2. Understand and appreciate heterogeneous catalytic and non-catalytic reactions for designing solutions for complex chemical engineering problemsCLO3. Design flexibly solid catalysts for investigating complex chemical engineering problemsCLO4. Understand and appreciate representative catalytic and non-catalytic reactors for investigating complex chemical engineering problemsCLO5. Design flexibly heterogeneous catalytic and non-catalytic reactors for investigating complex chemical engineering problems

CLO1. Catalysis, catalyst

CLO2. Heterogeneous catalytic and non-catalytic reactions

CLO4. Representative catalytic and non-catalytic reactors

Appreciate Design flexibly

CLO3. Solid catalysts

CLO5. Heterogeneous catalytic and non-catalytic reactors

PO3 PO4

Assessment & Time TableTest -40%Assignment -10%Final examination -50%

Week Time & Venue123456789

1011121314  

Chapter 1Introduction and fundamental of catalyst

1. Importance of catalyst and catalyst technology1) Ammonia synthesis2) Petroleum refining

2. Introduction to homogeneous and heterogeneous catalysis

Nitrogen circulation by living creatures

N2

NO3- NO2

- NH4+ Amino acids Proteins

Fixation by microbes200 million ton/year

Ammonia synthesisSOCIETY

At the end of the 19th century, demand for the basic fertilizers P, K and N increased in Europe because of increase in population.

In 1908, Haber realized it is important to develop catalytic reactor for the synthesis.

In 1913, the first commercial plant capable of 10 tons of ammonia per day was built in Germany.

ACADEMIAControversy on the equilibrium constant of :N2 + 3H2 = 2NH3

H(500ºC)=-109kJ/mol-N2

ACADEMIAIn 1904, NH3 was synthesized from N2 and H2 by Haber et al.

Today, more than 600 large scale plants worldwide, the annual production is over 160 million tons (-> 80% fertilizer).

Fe-Al2O3-K2O

Alkali promoted Ru/C or Ru/MgO

Effects of temperature and pressure on NH3 equilibrium

Catalysis Society of Japan, Basic Industrial Catalytic Reactions, Kohdan-sha (1985).

NH

3 co

ncen

trat

ion

[%] 101.3kPa, 300K

Eq. NH3 = 98%

Required to raise the temp. in order to obtain sufficient catalytic activity.

P [kg/cm-2]

Labo reactor for NH3 synthesis used by Haber

H2 + N2

High pressure circulating pimp

Condenser

Catalyst bed

Heater

High pressure vessel

Liquefied ammonia

Catalysis Society of Japan, Basic Industrial Catalytic Reactions, Kohdan-sha (1985).

Commercial plant for ammonia synthesis

Catalyst bed

Liquefied ammonia

H2 + N2

Compressor

Ammonia condensation

C. H. Bartholomew et al., Fundamentals of Industrial Catalytic Processes 2nd ed., Wiley Interscience (2006).

Nitrogen fertilizer consumptionC

on

su

mp

tio

n [

Mill

ion

to

n-N

/ye

ar]

Year

Russia + East Europe

Europe

Asia

Other

H. Kawashima, World Food Production and Biomass Energy, Tokyo Daigaku Shuppan-kai (2008).

Wheat yield in FranceY

ield

[t/

ha

]

Year

The first NH3 plant

Annual NH3 production2.7 million ton (worldwide)

Annual N consumptionas N fertilizer (worldwide)12 million ton

60 million ton

85 million ton

H. Kawashima, World Food Production and Biomass Energy, Tokyo Daigaku Shuppan-kai (2008).

The effect of N fertilizer on yieldY

ield

[t/

ha

]

Applied N fertilizer [kg-N/ha]

VegetablesCrops

Japan

H. Kawashima, World Food Production and Biomass Energy, Tokyo Daigaku Shuppan-kai (2008).

Applied amount of N fertilizer/field area

Year

Ap

plie

d N

fer

tiliz

er

[kg

-N/h

a]

East Asia

West Europe

South Asia

West Africa

H. Kawashima, World Food Production and Biomass Energy, Tokyo Daigaku Shuppan-kai (2008).

Crop production increase sustains population increase

Year

Re

lati

ve

ma

gn

itu

de

Annual crop production

Population

Annually, 350 kg-crop per capita

H. Kawashima, World Food Production and Biomass Energy, Tokyo Daigaku Shuppan-kai (2008).

40% as crop60% as meat via feed grains for domesticated animals

Global nitrogen circulationStratosphere

Troposphere

E. Sakurai et al., Introductory Plant Physiology, Baifuh-kan, Tokyo (1989).

LandSea

Organic N Organic N

Sediment

Introduction and fundamental of catalyst

1. Importance of catalyst and catalyst technology1) Ammonia synthesis2) Petroleum refining

2. Introduction to homogeneous and heterogeneous catalysis

Crude oil distillation and refining

Crudeoil

C. H. Bertholomew et al., Fundamentals of Industrial Catalytic Processes 2nd ed., Wiley Interscience (2006).

Crude oil distillation and refining

Important catalytic reactions for refining(upgrading distilled crude oil)

1) Removing nitrogen, sulfur, oxygen and metal compounds S and metal; to prevent catalyst deactivation at downstream processes S and N; to reduce fuel NOx and fuel SOx

2) Cracking of heavy fractions To obtain more light fractions (smaller carbon numbers) Heavy gas oil (C20-C40, 350-500ºC) and vacuum residue (>C40, >550ºC) are cracked to gasoline range hydrocarbons (C5-C10, 70-220ºC)

3) Reforming of naphtha To improve gasoline quality (octane number) Naphtha (alkanes and cycloalkanes of C5-C10) is converted to branched alkanes and aromatics.

Reason for cracking & reforming1. Difference between composition of crude oil and demand2. Increase in demands of light and high octane components

BP Statistical Review of World Energy 2008

Introduction and fundamental of catalyst

1. Importance of catalyst and catalyst technology1) Ammonia synthesis2) Petroleum refining

2. Introduction to homogeneous and heterogeneous catalysis

Homogeneous and heterogeneous catalysis

CatalystA catalyst is a substrate that affects the rate of a reaction.

CatalysisThe acceleration of a reaction by a catalyst.

Usage exampleAmides are hydrolyzed to ammonium salts with catalysis by acids or a alkalis. The acids or alkalis act as a catalyst.

Concrete

Abstract

Homogeneous and heterogeneous catalysis

Basically, the principle of catalysis is the same.

When it occurs on solid surface, it is called heterogeneous catalysis.

When it occurs in homogeneous phase such as liquid phase, it is called homogeneous catalysis.

A

A*(without cat)

B

Reaction coordinate

Ene

rgy

leve

l

A* (with cat)

A → A* → B

Reactant ProductActivated complex

(unstable, short life)

Homogeneous catalytic reaction

Partial oxidation of ethene to produce acetaldehyde (Wacker reaction)

H2C=CH2 + H2O + PdCl2 → CH3CHO + Pd + 2HCl (1)

Pd + 2CuCl2 → PdCl2 + 2CuCl (2)

2CuCl + (1/2)O2 + 2HCl → 2CuCl2 + H2O (3)

H2C=CH2 + (1/2)O2 → CH3CHO (1) + (2) + (3)

Overall reaction

Ethene partial oxidation

Pd2+ regeneration

Cu2+ regeneration

Catalytic

Homogeneous catalytic reactionThe details of the step (1) of Wacker reaction:

Activated complex

B. C. Gates et al., Chemistry of Catalytic Processes, McGraw Hill (1999).

Industrially relevant homogeneous catalytic reaction and catalyst

C. H. Bertholomew et al., Fundamentals of Industrial Catalytic Processes 2nd ed., Wiley Interscience (2006).

Enzymatic reaction

A. L. Lehninger et al., Principle of Biochemistry 2nd ed., Worth Publishers (1993).

TCA cycle

An example of enzyme

- Rubisco in tobacco- MW 550,000- The enzyme for producing biomass from CO2

Why does a catalyst have this kind of porous structure?

H. S. Fogler, Elements of Chemical Reaction Engineering 4th ed., Pearson Education (2006).

Heterogeneous catalytic reaction -overall-

A typical structure of heterogeneous catalyst

C. H. Bertholomew et al., Fundamentals of Industrial Catalytic Processes 2nd ed., Wiley Interscience (2006).

Heterogeneous catalyst-the reason for fine partciles

Heterogeneous catalyst -the reason for porous structure-

Typical pore structure of catalyst (support)

C. H. Bertholomew et al., Fundamentals of Industrial Catalytic Processes 2nd ed., Wiley Interscience (2006).

Heterogeneous catalytic reaction -intrinsic reaction (overall)-

→ Hydrogenation of ethene ← Dehydrogenation of ethane On metal (Pt, Ni etc) surface

PtCH2=CH2 + H2 ↔ CH3CH3

Heterogeneous catalytic reaction -intrinsic reaction (mechanism)-

Reaction mechanism(Langmuir-Hinshelwood type, abbreviated as L-H type)

B. C. Gates et al., Chemistry of Catalytic Processes, McGraw Hill (1999).

*: Active site of the catalyst such as Pt or Ni

Idea of ‘controlling step’

Two extremes. How about the intermediate condition?

C. H. Bertholomew et al., Fundamentals of Industrial Catalytic Processes 2nd ed., Wiley Interscience (2006).

Comparison of homogeneous and heterogeneous catalysts

C. H. Bertholomew et al., Fundamentals of Industrial Catalytic Processes 2nd ed., Wiley Interscience (2006).

Measures of reaction rates

O. Levenspiel, Chemical Reaction Engineering Third edition, John Wile&Sons (1999).

Measures of reaction ratesHomogeneouscatalytic

Heterogeneouscatalytic

Homo-geneous non-catalytic

Hetero-geneous non-catalytic

No Yes? No No

Yes Yes No No

No Yes (Short time use in lab)

No No

No Yes (Analysis for one particle)

No No

Yes No Yes Yes

No No No Yes

cat.