Page 69 - Subyek Encyclopedia - Encyclopedia of Separation Science

64 I / CRYSTALLIZATION/ Derivatization

which are the most mature in terms of their evolu- approach to separations, and will be better under-
tionary development, although it is widely recognized stood and correctly employed if we abandon the
that column liquid chromatography still lacks a sensi- current trend to compartmentalize the technique
tive and universal detector for general applications. based on specialization in individual subject areas.
This void may be Rlled by mass spectrometry, which
has made great strides in the last few years towards See Colour Plate 3.
this goal based on particle-beam interfaces and atmo-
spheric ionization techniques coupled with the devel- Further Reading
opment of low cost mass separators. By comparison,
thin-layer chromatography and supercritical Suid Berger TA (1995) Packed Column Supercritical Fluid
chromatography have become recognized as tech- Chromatography. Cambridge: Royal Society of Chem-
istry.
niques with niche applications and are unlikely to Braithwaite A and Smith FJ (1996) Chromatographic
supplant gas and column liquid chromatography as Methods. London: Blackie Academic & Professional.
the dominant chromatographic methods used in ana- Giddings JC (1991) UniTed Separation Science. New York:
lytical laboratories. The microcolumn techniques of Wiley-Interscience.
capillary electrophoresis, micellar electrokinetic Guiochon G and Guilleman CL (1988) Quantitative Gas
chromatography, and capillary electrochromatogra- Chromatography for Laboratory Analysis and On-Line
phy have quickly established themselves as useful Process Control. Amsterdam: Elsevier.
laboratory methods and are likely to become of in- Guiochon G, Shirazi SG and Katti AM (1994) Funda-
creasing importance as they complete their evolution- mentals of Preparative and Nonlinear Chromatography.
Boston: Academic Press.
ary cycle. In particular, the infant capillary electro-
Heftmann E (1992) Chromatography, Parts A and B. Am-
chromatography has the potential to replace column
sterdam: Elsevier.
liquid chromatography from many of its traditional
Jennings W, Mittlefehldt E and Stremple P (1997)
separation roles, but has yet to reach a state of devel- Analytical Gas Chromatography. San Diego: Academic
opment to be considered as a routine laboratory tech- Press.
nique. Lee ML, Yang FJ and Bartle KD (1984) Open Tubular
The only thing that is certain about science is un- Column Gas Chromatography. Theory and Practice.
certainty. Although chromatographic methods are New York: Wiley-Interscience.
likely to dominate separation science for the Rrst part Li SFY (1992) Capillary Electrophoresis. Principles, Prac-
of the twenty-Rrst century, it would be a foolish tice and Applications. Amsterdam: Elsevier.
person who predicts their form, continuing develop- Poole CF and Poole SK (1991) Chromatography Today.
ment, and main applications. Throughout the history Amsterdam: Elsevier.
of chromatography general approaches have had to Robards K, Haddad PR and Jackson PE (1994) Principles
and Practice of Modern Chromatographic Methods.
adapt to changing needs brought about by dramatic London: Academic Press.
shifts in the focus on different types of applications, Sherma J and Fried B (1997) Handbook of Thin-Layer
and this has a signiRcant impact on the relative im- Chromatography. New York: Marcell Dekker.
portance of the various techniques. However, Snyder LR, Kirkland JJ and Glajch JL (1997) Practical
chromatography should be considered as an holistic HPLC Method Development. New York: J Wiley.

CRYSTALLIZATION

H. J. M. Kramer and G. M. van Rosmalen, however, the dispersed phase consisting of numerous
Delft University of Technology, Delft, The Netherlands solid particles also forms the Rnal product, that has to
meet the required product speciRcations. Crystalliza-
Copyright ^ 2000 Academic Press
tion can thus also be seen as a technique to obtain
solid products, where the crystallization process has
to be carefully controlled in order to meet the ever-
Introduction
increasing demands of the customer on particle
Crystallization from solution is a separation tech- properties like particle size distribution, crystal
nique where a solid phase is separated from a mother shape, degree of agglomeration, caking behaviour
liquor. In contrast to other separation processes, and purity. Since the particles must also be easily