[kg/h] heat duty [kW] [EMIM] - Swinburne University of Technology

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5 Δεκ 2012 (πριν από 8 χρόνια και 8 μήνες)

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Melbourne 2006

Prof. Arlt

1

Chemie
-

und Bioingenieurwesen

Chemical engineering post the oil age

by

Wolfgang Arlt


Chair Professor at the university of Erlangen/Bavaria

Germany

Wolfgang.Arlt@cbi.uni
-
erlangen.de

Friedrich
-
Alexander
-
Universität Erlangen
-
Nürnberg

Melbourne 2006

Prof. Arlt

2

new goals of chemical engineering

1. Nanotechnology

Particles just above the size of melcules show new properties. The scientific
description is in the transfer region of thermodynamics and mechanical
engineering.

2. recovery of bio
-
products/natural products

Biotechnology slowly plays a more and more important role in the production of
mass products. These products cannot be separated by all unit operations.

3. release of pharmaceuticals

During the last 50 years new chemicals as pharmaceuticals were discovered.
Today the targeting of pharmaceuticals to the site of action is a topic.

4. climate change

A considerable increase in the mean temperature is related to anthropogenic CO
2
.
CO
2

can be avoided or separated and temporarily stored.



Melbourne 2006

Prof. Arlt

3

.

chromatography

tomography



Melbourne 2006

Prof. Arlt

4

correlation between production cost and production mass

Produktionskosten [

/kg]
Produktmengen/Jahr [Mt/a]
production per year in Mt


production cost per kg in


FCH: fine chemicals; Agro: agro
-
chemicals



Melbourne 2006

Prof. Arlt

5

what is chromatography?

(mobile
phase)

We have 2 tools for the separation in our hand:


stationary phase


mobile phase

The separation mechanism is a distribution between the stationary and mobile
phase.

Technical scale:


column diameter up to 12 m


continuous process (SMB)



Melbourne 2006

Prof. Arlt

6

pilot plant chromatographic columns

10 cm



Melbourne 2006

Prof. Arlt

7

factors influencing the performance of chromatography

1. Selection of the stationary and mobile phase

resolution, capacity, availability, mechanical stability, time of operation, cost


2. flow through the packed column

HETP, resolution



Melbourne 2006

Prof. Arlt

8

flow in a column: simulation and real column

influence of the frit



Melbourne 2006

Prof. Arlt

9

flow in a column

application of tomography for chemical engineering

z* = z/L =
0,9

0,7

0,5

0,3


Mobile phase


A: dist. water


B: potassium iodide in
dist. water (c = 50g/l)



Siemens Somatom Plus
4
th
-
Generation CT
Scanner


thickness = 2mm


scan time = 2s

A

B











Melbourne 2006

Prof. Arlt

10

intra
-
column

breakthrough behaviour


Observation of the intra
-
column breakthrough
behavior:


5% KI/H
2
O replacing H
2
O


ID50 ; z/L = 0.5


u
superficial

= 0.017cm/s


Convex band shape


preceeding front in the core


subsequent breakthrough in
the vicinity of the wall


Parabolic shape is
characteristic for non
-
optimized distribution
systems
1
.

1
A.

Brandt et al.,


J. Chromatogr. A, 796 (1998)
223

t = 365s

t = 402s

t = 432s

t = 453s

t = 473s

t = 492s

t = 514s

t = 555s

Melbourne 2006

Prof. Arlt

11

internal „break
-
thru“ curves

0,00
0,20
0,40
0,60
0,80
1,00
200
300
400
500
600
700
800
900
Zeit [s]
S
_Kaliumjodid
z/L=0,3
z/L=0,5
z/L=0,7
z/L=0,9
time [s]

conc. potassium iodide



Melbourne 2006

Prof. Arlt

12

summary of this chapter

1. Bio
-
products need „fine“ separation methods.

These methods must differ between small changes of the molecule‘s
structure (enantiomers, anti
-
bodies).


2. Bio
-
products allow for high separation cost.


3. „Fine“ separation methods must be flow
-
optimized.

Tomography based on H
-
NMR or X
-
ray and developed for medical
purposes allows a deep inside into the flow inside an apparatus
(micro
-
chemical engineering)



Melbourne 2006

Prof. Arlt

13

.

drug delivery



Melbourne 2006

Prof. Arlt

14

role of chemical engineering

Targeting of the drug to the site of action is topic of present research.


Role of chemical engineering

1. The pathway of a drug to the site of action is a series of dissolution and
membrane processes. These steps can be described by regular
thermodynamics and mass transfer laws.

2. Appropriate carriers can improve the mentioned steps.

3. Chemical engineering provides techniques like supercritical gas loading
in order to avoid organic solvents.



Melbourne 2006

Prof. Arlt

15

(SiO
2
)
n


Silica Aerogel

:


Highly porous, nanoscopic material




density:


0.003
-
0.35 g/cm
3



refractive index:


1.0
-
1.05



sound velocity:


100 m/s



thermal conductivity:

0.017 W/mK



porosity:


90
-
99 %



surface area:


600
-
1000 m
2



Young`s modulus

106 N/m
2


properties of silica aerogels



Melbourne 2006

Prof. Arlt

16

steps to make drug
-
loaded aerogels


condensation reaction


supercritical drying


(for hydrophobic aerogels: reaction with gaseous alcohol)


dissolution of the drug in a supercritical gas


adsorption from supercritical fluid on aerogel

advantages


equal load of aerogel ensured by thermodynamics


no milling and mixing process



Melbourne 2006

Prof. Arlt

17

maximum loading of aerogels


Drug


Loading of drug in aerogel [wt %]

Ketoprofen

30

Griseofulvin

6
.
3

Miconazol

60

Dithranol

4
.
4

Flurbiprofen

18

Ibuprofen

73

experimental condition: hydrophilic aerogels from saturated solutions in
CO
2

at 180 bar, 40
°
C.



W. Arlt; I. Smirnova; K.
-
P.
Yoo; S.Y. Kim;
Verfahren
zur Beschleu
-
nigung der
Herstellung von
Aerogelen,
Dt.
Patentanmeldung DE
100 48 654 v. 26.9.2000

Melbourne 2006

Prof. Arlt

18

delivery of Griseofulvin from different sources

nano
-
particle
200
nm (RESS)

crystalline

milled

from aerogel



% released

time [min]

Melbourne 2006

Prof. Arlt

19

mechanism of ultra
-
fast release


drug on

aerogel aerogel network destroyed by capillary forces











Water



Water

Melbourne 2006

Prof. Arlt

20

.

ionic liquids



Melbourne 2006

Prof. Arlt

21

choice of entrainer in extractive distillation

Entrainer

Feed

A+B

pure
distillate A

2nd component B

+ entrainer

An entrainer influences the activity coefficients
of at least 1 component in the separation factor
and is high
-
boiling

2
LV
2
1
LV
1
2
1
2
1
2
1
12
P
P
y
x
x
y
K
K






Criteria for a best
-
suited entrainer

1.
large separation factor at low entrainer
concentration

2.
negligible vapour pressure: no entrainer in the
distillate and no separation internals in the top
of the column

3.
energy efficient recovery of entrainer (low
reflux ratio)



Melbourne 2006

Prof. Arlt

22

.



what are Ionic Liquids?

N
+
R1
R2
R1
R1
P
+
R1
R2
R1
R1
Cation

Anion

imidazolium
-
ion

pyridinium
-
ion

phosphonium
-
ion

ammonium
-
ion

Cl
-

acetate

...

N
R
+
N
N
R2
R1
+
alkylsulfonate

alkylsulfate

tosylate

dialkylphosphate

designable

cations and anions

extremely low vapour pressure

liquid at ambient temperature, wide liquid range

non explosive

most are not harmfull

Melbourne 2006

Prof. Arlt

23

savings of energy: comparison of non
-
volatile and common
entrainer for ethanol
-
water

2900

3100

3300

3500

3700

3900

4100

4300

4500

8000

12000

16000

20000

24000

28000

32000

entrainer mass flow [kg/h]


heat duty [kW]

[EMIM] [BF4]

hyperbr. polyglycerol PG

1,2
-
ethanediol

area of reduced heat duty








results with non
-
optimized ionic
liquids

Melbourne 2006

Prof. Arlt

24

.

climate



Melbourne 2006

Prof. Arlt

25

The climate is endangered!

It is no more important, if there are disbelievers, it is a political fact.

Chemical engineering plays an important role.

The Kyoto protocol has a political impact, not on climate.


The real savings in CO
2

emissions are:

Germany

Kyoto

-
21% (compared to 1990, supported by the break
-
down



of East

German industry)

needed

-
80%

Australia

promised an increase by 8% only



Melbourne 2006

Prof. Arlt

26

Chemical engineering takes part in 2 areas of climate protection in
electrical power plants:


1.

separation of CO
2

in existing or new power plants


2.

interim storage in the underground or in the sea

focusing on electricity



Melbourne 2006

Prof. Arlt

27

capture: solvents

solvent

capacity

Δ
H
GL

kJ/kg

T
reboiler


Monoethanolamine

0,5 mol/mol MEA (theoretical load)

1844

120
°
C

MDEA

1 mol/mol MDEA (theoretical load)

1285

120
°
C

PSR

(mixed amines and
physical solvents)

20
-
80% more CO
2

is absorbed per
unit volume of solvent

compared
to MEA

77% of
MEA

110
°
C

KS
-
1

1 mol/mol KS
-
1

(theoretical load)

85% of
MEA

110
°
C

Cansolv

1 mol/mol (theoretical load)

??

110
°
C

Rectisol

@
-
30
°
C,10 atm: 0.454 mol/mol

@
-
30
°
C,1 atm: 0.026 mol/mol

507

Melbourne 2006

Prof. Arlt

28

storage of CO
2
: rock

graph after Dominik, TU Berlin

Speicherung

in Kavernen

Speicherung

in ehem.

Öl od. Gasfeldern

CO
-
Fluten

in Ölfeldern

2

Speicherung

in Saline Aquifere

Speicherung

in nicht abbauwürdigen

Kohleflözen

Speicherung bei der

Flözgasgewinnung

Injiziertes CO

2

CO Injektion

2

Öl
-

oder Gas
-
Produktion

in saline aquifers

enhanced oil
recovery

in caverns

in oil and
gas fields

produce seam gas

in coal seam


injected CO
2

CO
2

injection

oil and gas prod.



Melbourne 2006

Prof. Arlt

29

storage of CO
2
: ocean (the natural option)

deep sea

flat water

liquid CO2

liquid CO2

CO gas

2

200 ~ 400 m

1000 ~ 3000 m

>3400 m

CO
-
hydrate

2

liquid CO2

1 phase or 2
phases

The storage is a
mixing problem:
+11,5

mol C / kg
seawater (DIC)

SLL
-
equilibrium

gas solubility

compressibilty

pressure
-
dependent
density



Melbourne 2006

Prof. Arlt

30

Thermodynamical considerations for sequestration in rocks

Melbourne 2006

Prof. Arlt

31

Montmorillonite

63
-
90
μ
m


Adsorption by dry mineral *)


100 g CO
2
/kg (40
°
C, 90 bar)



Solubility in brine


45 g CO
2
/kg (37
°
C, 90 bar)



Trapping as a supercritical fluid


ρ
CO
2

= 485,5 kg/m
3

(40
°
C, 90
bar)




221 kg CO
2

5,7 kg CO
2

14,5 kg CO
2




1 m
3


241 kg CO
2
/m
3

Example of estimation of storage
capacity for CO
2

in Montmorillonite:

3%
supercritical CO
2

85% rock

85% rock

12%
brine

15%
pore volume

virgin

after CO
2
sequestration

sequestration: thermodynamical considerations



*) in the case of fine powder

Melbourne 2006

Prof. Arlt

32

Montmorillonite, 40°C
0
0,05
0,1
0,15
0,2
0,25
0,3
0
20
40
60
80
100
120
140
pressure (bar)
g CO2/g sample
mixture with water
dry sample
sequestration: adsorption data of a clay

Montmorillonite is regarded to be a seal!

A technical seal does not show absorption neither adsorption.

data includes a (small) amount of surface reaction



Melbourne 2006

Prof. Arlt

33

conclusion from the view of chemical engineers

1.
Chemical engineers
-
as in the past
-

must cooperate with other
disciplines, now with medical doctors, geologists and meteorologists

2.
Oil
-
based processes has been developed to a high standard

3.
New tasks are waiting

medicine

pharmacy

biotechnology

speciality products (nano
-
particles)

climate

4.
the curricula must be changed to the new goals

in Erlangen: MAP = advanced
m
aterials
a
nd
p
rocesses

5.
Thermodynamics will relate on molecular models

The profession „chemical engineering“ is needed in future!



Melbourne 2006

Prof. Arlt

34

Thank you for your patience!


I am happy to answer your
questions.

Melbourne 2006

Prof. Arlt

35

.



.