Application of Supercritical Fluids Abstract
Many advantages of supercritical fluids come
Supercritical water is expected to be useful in
from their interesting or unusual properties which
liquid solvents and gas carriers do not possess.
solubility solutes and molecular catalyses, solvent
Such properties and possible applications of
molecules under supercritical conditions gently
supercritical fluids are reviewed. As these fluids
solvate solute molecules and have little influence
on the activities of the solutes and catalysts. This
temperatures, supercritical drying is useful to
property would be attributed to the local density
prepare dry-gel. The solubility and other
fluctuations around each molecule due to high
important parameters as a solvent can be adjusted
molecular mobility. The fluctuations in the
supercritical fluids would produce heterogeneity
advantages as solvents for extraction, coating or
that would provide novel chemical reactions with
chemical reactions thanks to these properties.
molecular catalyses, heterogenous solid catalyses,
Supercritical water shows a high organic matter
solubility and a strong hydrolyzing ability.
Supercritical fluid, Supercritical water, Solubility, Solvation, Waste treatment,
applications development reached the initial peak
1. Introduction
during the period from the second half of the 1960s
There has been rising concern in recent years over
to the 1970s followed by the secondary peak about
supercritical fluids for organic waste treatment and
15 years later. The initial peak was for the
other applications. The discovery of the presence of
separation and extraction technique as represented
critical point dates back to 1822.1) The temperature
by the extraction of caffeine from coffee beans.
and pressure beyond the critical point are in the
Since the practical application in Germany in 1978,
supercritical state. As indicated in Table 1,2) critical
a number of practical plants have been in operation.
points are often in high pressure. Therefore, a high-
The secondary peak concerns decomposition of
pressure test facility (high temperature and high
organic (waste) substances, which started when the
pressure depending on the case) is required for a
U.S. Department of Defense began studies on using
systematic study of fluids in the near- or
supercritical water as a means for completely
supercritical state. This might have been the main
decomposing chemical weapons. And the tertiary
reason why studies in this field were comparatively
peak is about to come with mounting interest in the
possible development of new material program.
R&D Review of Toyota CRDL Vol. 35 No. 1
the force to make free thermal movement. At high
2. What are supercritical fluids?
temperature, however, the force of particles to move
Supercritical fluids are described as “fluids in the
about freely exceeds that of the inter-molecular force
temperature and pressure state of over the critical
if the inter-molecular distance is minimized under
point” as shown in Fig. 1. This definition, however,
pressure. The supercritical state is thus reached
is not sufficient and not providing a good
where no condensed phase is produced.
When the pressure rises, the gas density becomes
For persons handling them, they are not different
higher, however. The inter-molecular distance then
from “high-pressure gas.” They are not
becomes shorter, making it impossible to disregard
distinguishable from gas because they are in a non-
the effects of inter-molecular action. In other words,
condensed state, which disables handling without
when viewed from the molecules inside or from the
using a sealed container. In other words, they may
microscopic standpoint, they are in a state close to
be considered to be gas that does not transform to
liquid. If the molecular movement can be directly
the liquid phase with discontinuous change in the
observed, it is assumed to be as violent as in the
density when the pressure rises under a constant
gaseous state. When observed in a still photograph,
temperature. Substances change their phase
it may resemble that of the liquid. This is the reason
depending on the balance of forces between the
why “supercritical is the intermediate state between
force to form the liquid or solid phase by
condensation under inter-molecular attraction and
3. Characteristics of supercritical fluids
“Supercritical fluids in the intermediate state
between gas and liquid have high diffusivity
comparable with a gas and high solubility as a
liquid.” This is the popular description of
supercritical fluids. This expression may mislead us
to expect that supercritical fluids are wonderful
-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
Phase (Pressure-Temperature) diagram for CO2.
R&D Review of Toyota CRDL Vol. 35 No. 1
solvents that make two mutually opposed properties
be easily removed after completing the reaction by
compatible. As shown in Fig. 2, solubility rises as
returning it to the atmospheric pressure.
the density becomes higher under pressure,
In addition to these general characteristics, in the
simultaneously delaying diffusion, however. In
case of supercritical water, properties specific to the
addition, it is a fact that solubility is lower than
water expand the sphere of possible application,
liquid in a simple system, while the diffusion is
which will be described in detail in Section 5. 4. Application as extractant
Therefore, general descriptions of characteristics
of supercritical fluids are limited. Their
4. 1 Basic principle
characteristics in use differ by each field of
Solubility of supercritical fluids to various solutes
application to be stated later. They may be listed as
is not necessarily high compared with liquid. The
characteristics of using the supercritical fluids for
(1) Generate no liquid (condensed phase) under
extractants are shown in Fig. 2, and their solubility
pressure change or on solid surfaces.
can be continually changed to a large degree.
(2) Able to control density (solubility), polarity,
Moreover, since they do not form condensed phase,
viscosity and other properties of the fluids
they can infiltrate into very fine gaps of solids under
high pressure. These properties enable them to solve
(3) Can change the property sharply with very
a target substance efficiently from solids to be
little change in pressure as shown in Fig. 3,
particularly in the vicinity of the critical temperature
Large change in the solubility is the main reason
and pressure.3) This suggests that largely different
why supercritical fluids are used for extractants. To
state of property can be simultaneously realized near
realize efficient extraction, increase of solubility
the critical point with the addition of solutes,
itself is desirous, too. One of the effective means to
disturbances on the solid surfaces and fluctuations of
do this is to add a component for increasing the
solubility. This component is called an entrainer or
(4) Molecular association by inter-molecular
modifier. Generally, several percent of a component
actions or the formation of solvation structure of
that reacts strongly with the solute and which is
solute molecules is local and short-lived, hence not
soluble to the basic solvent is added. Such an
additive not only increases solubility, it also
(5) Gaseous substance under ordinary temperature
improves the separation characteristics by
and atmospheric pressure such as carbon dioxide can
controlling the solubility of the solvent. A lot of the
Diffusivity CO2 and solubility of naphtalene inCO2 at 40˚C.
R&D Review of Toyota CRDL Vol. 35 No. 1
research and development done on separation and
absorbents and other separation method.5) A method
extraction concern this entrainer (additive). Still
of setting the extraction condition on multiple stages
finer separation will become possible by combining
Around 1990, there were concentrated patent
4. 2 Applications examples
applications concerning the removal of organic
Measurement of solubility of substance to the
components, the molding binders, from ceramic
supercritical fluids was conducted about 50 years
injection moldings. These applications searched for
after the discovery of the above-mentioned
extract conditions13) without deforming the moldings
supercritical state. It was recognized that they have
at a temperature below the softening point of the
dissolving power close to that of the liquid.
resin. Many of the applications examined extraction
Research has been fully conducted since the
under high pressure of about 35 MPa at which the
extraction of caffeine from coffee beans was
density of carbon dioxide, which is the dissolving
patented in 1964.6) Since the practical application in
power, becomes saturated, while the temperature
Germany in 1978, commercial plants for extracting
was near the comparatively low critical temperature.
hop extract, perfume, tobacco nicotine, spices or
However, as stated earlier, since the dissolving
power of supercritical fluids is not as strong as that
Operation of those plants requires high pressure
of organic solvent liquids, they are not suitable for
(130°C, 35 MPa for processing coffee beans or
removing binders having high molecular weight but
extracting perfume), thus limiting the application to
for removing paraffin oil and other substance of low
foods and other high-value added products. A trial
conducted circa 1990 indicated that a perfume
In recent years, the number of cases directly
extraction plant7) with an annual production of about
associated with the composition of material15) with
800 tons required an equipment cost of some $3
the aim of improving the characteristics by removing
million and the processing cost of $1.10 (personnel
the component of low molecular weight from the
cost of $0.43 included) per kilogram while a
organic polymer has increased remarkably. Also
decaffein plant for coffee beans with an annual
there are a number of applications reflecting the
production of about 200,000 tons8) required an
rising concern of environmental problems. Reports
equipment cost of $34.5 million and a processing
have been made on the examination of hazardous
cost of $0.35 (personnel cost of $0.19 included) per
substances (organic chlorine, organic mercury, PCB,
kilogram. Reduction of production cost through
insecticide, herbicide, etc.) from soil,16) waste17) or
continuous processing, etc. is yet to be developed.
animal or plant tissues,18) and their removal
As thus far stated, research and development
conditions. In most cases, these cases provide the
concerning separation and extraction have
basic extraction data using carbon dioxide as the
continued. In Japan, application was made for about
base solvent and alcohol and/or water as the
80 patents during the 25 years from 1970 to 1995.
Most of the applications, however, state the novelty
Separation and extraction remain the central field
of the subject substance with only few stating
of application for supercritical fluids, where the
development beyond the content described in the
basic data are most richly accumulated. Application
basic principle stated in the preceding subsection.
as a cleaning solvent in semiconductor manu-
These applications related to foods are characterized
facturing19) is as an extension of this technology.
by the removal of grease and oil9) from grain,
cholesterol10) from eggs, residual agricultural
5. Decomposition of organic using supercritical
chemicals11) and other unnecessary or hazardous
substance from foods. Also separation and
5. 1 Specificity of supercritical water
extraction of neutral fat and phospholipid other fine
Water is the most commonly used solvent. It is a
separation12) were attempted. In these separations, a
most specific fluid having interesting properties.
combination was made with the above-mentioned
Because of its high critical points for temperature
R&D Review of Toyota CRDL Vol. 35 No. 1
and pressure, attention has recently been given to its
that water under critical temperature dissolves
inorganics easily and dissolves organics when over
The outline of the characteristics of water as a
the critical temperature where inorganic salt is
reactive solvent can be understood with an ionic
product and a dielectric constant. The ionic product
Since supercritical water requires high temperature
becomes the measure for interaction with hydrolysis
and pressure, commercial plants could not
and the dielectric constant with solutes.20) As Fig. 4
immediately be constructed. Nippon Shokubai
shows, water retains a comparatively high ionic
helped to ease this condition by using a catalyst.
product under pressure.3) On the other hand, its
This company carried on systematic studies on the
dielectric constant decreases remarkably near the
matter and applied for about 30 patents during the
critical point3) as shown in Fig. 5. That is,
period from 1989 to 1995. They mainly examined
supercritical water is a non-polar solvent of low
catalysts and reported that titanium and zircon
dielectric constant. It has the capability to dissolve
oxides,22) gold, palladium and other precious
organic compounds, simultaneously retaining active
metals23) or iron or copper ion additives24) were
state of high hydrolysis performance.
effective. On the other hand, Osaka Gas applied for
5. 2 Application to decomposition of organic
an almost identical number of patents in their
compounds
research for possibilities under critical temperature.
Patents applications for using water in the
They searched for a method of supplementing
subcritical (under critical temperature) to super-
incomplete decomposition reaction with precision
critical state as a solvent increased in 1989 and rose
filtration,25) biological and other processings.26)
In recent years, organic decomposition action
Moder, a venture company related to the chemical
using supercritical water itself that contains no
weapon decomposition project of the U.S.
oxidizer has attracted attention. Nishikawa Rubber
Departments of Energy and Defense applied for and
Company and Kochi University conducted joint
received a basic patent around 1989.21) Here,
efficient oxidative degradation is realized using the
devulcanization and oil development of vulcanized
properties of the oxidizing agent (oxygen), which is
rubber. They found that subcritical water with
soluble to the critical water with ease, in addition to
sulfuric absorbents added is effective for
the above-mentioned properties of supercritical
devulcanization and oil development27) and that
water. Furthermore, the company made it possible
to separate inorganics by adroitly using the property
R&D Review of Toyota CRDL Vol. 35 No. 1
supercritical water added with zinc oxide28) or
6. 2 Particulate manufacturing and coating
hydrochloric acid29) is effective in further promoting
technology - Use of extraction and
devulcanization and oil development. In addition,
crystallization growth by changing
Japan is the center of positive basic studies on the
solubility
reactions attributable to the solubility and high ion
It is possible to change the solubility of
product of supercritical water particularly from the
supercritical fluids sharply and continuously with
viewpoint of reaction rate control. Using
the pressure (density) of additives. Solubility drops
supercritical water realizes a cellulose decomposition
sharply when the high pressure in a container in
rate of 102 to 104 compared with conventional acid
which supercritical fluids are stored is discharged
catalyst-based decomposition.30) Based on the results
rapidly. During the process, solute is extracted and
of these basic studies, research has begun on the
inorganic or organic particulates are grown. This
decomposition of biomass31) and polymers32) or
method is called Rapid Expansion of Supercritical
improvement of coal or heavy oil quality.33)
Solution (RESS) by which growth of silica, alumina,
Development of devices for downsizing the reaction
zirconium and other inorganic oxides36) and
section by a using fast reaction rate is expected
medicines, polymers and other organic substances37)
along with operating cost reduction.
are verified. Particulates grown here are often non-
crystal, but when made to react under supercritical
6. Recent studies
water of high temperature, this method can form iron
6. 1 Manufacture of inorganic porous bodies
oxides, zirconia, titania (anatase), ceria and other
and use of supercritical drying
crystal particulates.38) Moreover, a single spraying
Supercritical drying is known as a method for
enables a microcapsule with the effect of the
applying supercritical fluids. This method removes
chemical content shielded with poly-lactic acid,
solvent by using the characteristics that make it
possible to change the density continuously from a
The spraying mechanism based on rapid expansion
density close to liquid to one close to gas without
resembles coating equipment. The above-mentioned
phase change. This method was used for preparing
composition, however, sprays only particulates and
samples for observation with an electron microscope
it is not possible to expect a uniform adhesion of the
from a biosubstance with a high water content. It is
particulates on the substrate. Union Carbide of the
possible to prevent contraction caused by the solid
U.S. began research on a method to substitute the
particles that condense when the water or other
coating solvent and the compressed air in the air
solvent dries by vaporization. Matsushita Electric
spray with supercritical carbon dioxide from the mid
Works applied this property for manufacturing
1980s. The company still continues its research and
inorganic oxide porous bodies.34) In water, alcohol
applied for a number of patents concerning the basic
and other solvents, clay mineral and inorganic
principle,40) paints and the solvent feeding method
particulates synthesized with sol gel reaction to form
during that period. To stably solve organic
a suspension or sol where these particulates are
polymers, which are the basic components of paint,
highly dispersed. Supercritical drying is effective
and realize about the same finish as ordinary
for drying the suspension or sol while retaining the
coatings, the company adds ordinary organic
suspended state as much as possible. By using this
solvents as well. It closely examines the process of
drying method, an inorganic porous solid is formed.
solution and extraction under the ternary system.41)
Spaces where the solvent molecules existed remain
Ideally, the polymer is solved in mixed supercritical
as voids. They are useful as heat insulators,
fluids of organic solvent and carbon dioxide in a
adsorbents or catalyst supports. In particular, a
high-pressure container as Fig. 6E shows.
combination of sol gel reaction and supercritical
Immediately after the spraying, the carbon dioxide
drying enables transparent inorganic porous solids
first vaporizes, leaving the organic solvent and
(aerogel)35) having density of under 0.01g/cc to be
polymer behind. After attaching itself to the base
material, the organic solvent vaporizes, forming the
R&D Review of Toyota CRDL Vol. 35 No. 1
polymer film just as ordinary paints do. The
controlled with ease for precision reaction including
principle may seem simple, but there are a number
stereochemistry. However, the catalyst and reaction
of problems, which include the sharp drop of the
molecules in the solution are often inactive as they
temperature during expansion, retention of viscosity
are always surrounded by a number of solvent
suitable to the coating and optimal composition,
molecules. Strong solvation to such solvents and
processing of pigments and other additives, the
reaction molecules often has a negative effect on the
spraying of high-pressure fluids of over 10 MPa, and
acceleration of reaction. The solvent least affects
so forth. Beside these, there is a long way to go
reaction in the gas phase when a solid catalyst is
before practical application can be achieved,
used. In this case, reaction is rapid because the
including reduction of hazardous organic solvents,
catalyst and reaction molecules are in naked state.
development of devices and operating costs. The
Control of reaction is difficult because of the
technology is quite interesting and important.
heterogeneity of the catalytic structure, however. 6. 3 Characteristics as synthesized organic
Furthermore, molecular catalysts cannot be applied
solvents - Specific intermolecular action
In the synthesis of substances, solvents are used to
The ideal catalytic reaction is a high-speed
accelerate or control the reaction. In this case, the
selective reaction provided with priority given to
solvent is first required to be able to solve the
both reactions in the gas and liquid phases. To
reactive material, catalyst or other additives. The
realize this, it is necessary to have a reaction system
characteristics when supercritical fluids are used for
to make molecular catalyst soluble and suppress
the reaction solvent are best described by Ikariya
deactivation caused by the catalyst to a minimum.
This is the reason why we are paying attention to
“To effect molecular catalytic reaction in a
supercritical fluids having intermediate properties
solution, solvents are used to form a uniform system
with catalyst and reaction molecules for, and
Based on this point, they succeeded in accelerating
effective mass transfer. To do this, molecular
the reaction by using supercritical carbon dioxide as
catalytic reaction in the liquid phase can be
the solvent in a reaction to form formic acid useful
as a chemical material from carbon dioxide and
hydrogen by using Ru-complex as the catalyst.43)
Moreover, it is found that reaction is further
accelerated by adding dimethylamine that is soluble
in supercritical carbon dioxide. This extracts formic
acid as amine salt insoluble in supercritical carbon
dioxide. “The intermediate property between liquid
and gas” mentioned here, that is, the “property that
makes molecules soluble but not inactive” is
attributable to the characteristics (4) of the
aforementioned supercritical fluids. Section 2 stated
that supercritical fluids can be handled as “gas of
high density.” From the viewpoint of the reaction
solvent, however, it is more understandable if we
think of it as liquid of intensive molecular motion.
Enzyme reaction is normally effected in an
aqueous solution. Here too, supercritical fluids are
being used as an interesting solvent for the very
same reasons as for molecular catalysts.44) In this
case, it is necessary to give consideration to the
Fundamentals of coating with supercritical fluids
inactivation of enzymes and other restrictions caused
R&D Review of Toyota CRDL Vol. 35 No. 1
by reaction between enzyme protein and carbon
; Inada, S. : Examined Patent Pub. H07-16373
dioxide. The characteristics of supercritical fluids
are utilized for accelerating high reaction, making
; Yoshida, O., et al. : Examined Patent Pub.
water-insoluble molecules react, forming organic
polymers of uniform molecular weight, etc.
10) Hasegawa, M., et al. : Unexamined Patent Pub.
7. Conclusion
11) King, J. W., et al. : J. Chromatogr. Sci., 31-1 (1993), 1
Supercritical fluids have a number of interesting
; Ahronson, N., Lehotey, S. J. and Ibrahim, M. A. :
and useful characteristics. Above all, the viewpoints
J. Agric. Food Chem., 42-12(1994), 2817
of Noyori et al. in the preceding section are
12) Montanari, L., et al. : J. Food Sci., 61-6(1996), 1230
considered to be the most important and interesting.
13) Nakajima, N., et al. : Examined Patent Pub.
The characteristics of supercritical fluids are that
while they form a uniform solution system as a
; Ishihara, M., et al. : Unexamined Patent Pub.
whole, they simultaneously realize a heterogeneous
state where the surrounding conditions of the
; Mizuno, S. : Unexamined Patent Pub. S63-11577
molecules are in constant change with violent
fluctuations. Because of such fluctuations,
; Ishihara, M., et al. : Unexamined Patent Pub.
supercritical fluids are a solvent that can realize
advantages of both liquid and gas simultaneously.
; Masuoka, H., et al. : Examined Patent Pub.
One of the interesting fields for future research
and development would be to make positive studies
14) Chartier, T. M., Ferrat, M. and Baumard, J. F. :
and use of the fluctuations including solid surfaces,
"Supercritical debinding of injection molded
adsorption or heterogeneous catalytic reaction.
ceramics", J. Am. Ceram. Soc., 78(1995)1787
15) Kimura, M., et al. : Unexamined Patent Pub.
Referrence
1) Taylor, L. T. : Supercritical Fluid Extraction (1996), 1,
; Pub. Jpn. Transl. PCP. H06-511278 (in Japanese)
; Oka, H., et al, : Unexamined Patent Pub.
2) Unexamined Patent Pub. H03-207436 (in Japanese)
3) Inomata, H. : Chourinkairyutai no Youbaibussei to
16) For example, Snyder, J. L., et al. : J. Chromatogr. Ouyou Gijutsu, Ed. by Yamazaki, N., (1998), 681
4) Ikariya, T. and Noyori, R. : Gendaikagaku
17) For example, Kawamoto, K., et al. : Dai 3 kai
(in Japanese), 5(1996), 43 Kankyou Kagaku Touronkai Kouen Youshishu (in
5) Iwai, Y., et al. : Ind. Eng. Chem. Res., 33-9(1994),
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18) For example, Hale, R. C., et al. : Int. J. Environ.
6) Zosel, K. : German Patent No.1, 493, 190 (1964)
Anal. Chem., 64(1996), 11
7) Novak, R. A. and Robey, R. J. : ACS Symp. Ser.,
19) Jpn. Transl. PCP. H59-502137 (in Japanese)
406(1989), 511
; Kaminaga, K. and Okada, J. : Unexamined Patent
8) Layers, W., Novak, R. and Linnig, D. A. : Proc. of
2nd Int. Symp. Supercritical Fluids, (1991), 261
; Furue, T., et al. : Unexamined Patent Pub.
9) Taniguchi, M., et al : Examined Patent Pub.
; Minamihonoki, K. : Unexamined Patent Pub.
; Ito, N., et al. : Examined Patent Pub. H03-78096
20) Yamazaki, N. and Yamazaki, Y. : Nihon Bunkou
; Ito, N., et al. : Examined Patent Pub. H04-21548
21) Examined Patent Pub. H01-38532 (in Japanese)
; Hayakawa, K. and Kitamura, I. : Examined Patent
22) Mitsui, K., et al. : Examined Patent Pub. H06-2227
R&D Review of Toyota CRDL Vol. 35 No. 1
23) Mitsui, K., et al. : Unexamined Patent Pub.
36) Matson, D. W., Peterson, R. C. and Smith, R. D. :
Adv. Ceram. Mater., 1-3(1986), 242
; Yamaguchi, Y. et al. : Unexamined Patent Pub.
37) Griscik, G. J., Rousseau, R. W. and Tja., A. S. :
"Crystallization of n-octacosane by the Rapid
24) Mitsui, K., et al. : Unexamined Patent Pub.
Expansion of Supercritical Solusions", J. Cryst.
Growth, 155(1995), 112
25) Kijima, J., et al. : Unexamined Patent Pub.
38) Adsciri, T., Kanazawa, M. and Arai, K. : J. Am.
Ceram. Soc., 75(1992), 1019
26) Yamada, N., et al. : Unexamined Patent Pub.
39) Kim, J-H., Paxton, T. E., Tomasko, D. L. :
"Microencapsulation of Naproxen Using Rapid
27) Yamazaki, N., et al. : Unexamined Patent Pub.
Expansion of supercritical Solusions", Biotech. Prog.,
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28) Yamazaki, N., et al. : Unexamined Patent Pub.
40) Examined Patent Pub. H06-57336 (in Japanese)
41) Unexamined Patent Pub. H04-260460 (in Japanese)
29) Yamazaki, N., et al. : Unexamined Patent Pub.
42) Noyori, R. : The TRC News, No.56(1996), 1
43) Ikariya, T., et al. : Unexamined Patent Pub.
30) Adschiri, T., et al. : "Noncataltic Conversion of
Cellulose in Supercritical Water", J. Chem. Eng. Jpn.,
; Ikariya, T., et al. : Unexamined Patent Pub. 26-6(1993), 676
31) Arai, K. : Energy and Resources (in Japanese),
; Ikariya, T., et al. : Unexamined Patent Pub. 16-2(1995), 175
32) Enomoto, H., et al. : Unexamined Patent Pub.
44) Randolph, T. W., et al. : Biotechnol. Lett., 7(1985),
33) Enomoto, H., et al. : Unexamined Patent Pub.
34) Takahama, K. : Examined Patent Pub. H05-77606
Yoshiaki Fukushima Year of birth : 1949
; Takahama, K. : Examined Patent Pub. H05-71546
Academic degree : Dr. Eng. Academic society : Jpn. Inst. Met., Chem.
35) Takahama, K. : Examined Patent Pub. H03-257027
R&D Review of Toyota CRDL Vol. 35 No. 1
FEMA Cross-reference List This is a cross-reference list of addresses to the August 29, 2008 FEMA list of structures that are not located in the Special Flood Hazard Area. The flood plain gods have smiled on you! The page numbering starts with the first page of addresses - not the FEMA cover letter. The FEMA list has several typo's and omissions. So when there is a cross-reference to a
Title: How to manage risky drinkers in Primary Health Care Authors: Acknowledgements: This guide has been writen in accordance with the criteria of the PHEPA Training Programme on identification and brief interventions and the PHEPA Clinical Guidelines on identification and brief interventions. It is also inspired in ‘Helping patients who drink too much. A clinician’s guide. 2005 Edition’ fr