Project Details Separation - Revision of the Orange Book CHAPTER 4

Project No.:
Start Date:
01 January 2012
End Date:
08 January 2018
Division Name:
Analytical Chemistry Division
Division No.:


To prepare a revised vocabulary of concepts and terms in separation sciences that is compatible with the glossary format used in the Gold Book. (Orange Book online version is accessible at

> Orange Book (4th edition) draft content: project 2012-005-1-500


The last edition of the Orange Book was published in 1998. Analytical chemistry has moved into new fields of science, and the importance of some areas has changed. The revision of the Orange Book is a major endeavor of the Analytical Division and is expected to take until 2015.

With the development of modern science and technology, many of the terms are outdated. In the meantime, more and more new terms in the field of separation methods (traditional separation, chromatography in all forms, electrophoresis, ion mobility, membrane separation) have appeared or are emerging. The relating new methods have been established or are being developed. Furthermore, some terms in the old version of separation methods are not correct on the basis of strict scientific significance, even completely wrong.
Briefly, the new Chapter 4 will include:

4.1. Introduction

4.2. Chromatography

4.3. Ion Exchange

4.4. Liquid-Liquid Distribution (Solvent Extraction)

4.5. Electrophoresis

4.6. Centrifugation

4.7. Membrane Separation

4.8. Reference


Feb 2014 update – A preliminary text of Chapter 4 has been drafted and shared with all members of the project task group for discussion. The Task Group plans to meet in Hungary at the end of March to finalize the text.

Feb 2017 update – The provisional recommendations titled “Terminology of Separation Methods” is available for public review till 30 June 2017.

Jan 2018 update – The IUPAC Recommendations is published in PAC Volume 90, Issue 1, Pages 181–231,

Project complete

Last update 8 Jan 2018