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Chemical Analysis Modern Instrumentation Methods and Techniques Second Edition Francis Rouessac and Annick Rouessac University of Le Mans, France Translated by Francis and Annick Rouessac and Steve Brooks Chemical Analysis Second Edition Chemical Analysis Modern Instrumentation Methods and Techniques Second Edition Francis Rouessac and Annick Rouessac University of Le Mans, France Translated by Francis and Annick Rouessac and Steve Brooks English language translation copyright © 2007 by John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex PO19 8SQ, England Telephone (+44) 1243 779777 Email (for orders and customer service enquiries): [email protected] Visit our Home Page on www.wiley.com Translated into English by Francis and Annick Rouessac and Steve Brooks First Published in French © 1992 Masson 2nd Edition © 1994 Masson 3rd Edition © 1997 Masson 4th Edition © 1998 Dunod 5th Edition © 2000 Dunod 6th Edition © 2004 Dunod This work has been published with the help of the French Ministère de la Culture-Centre National du Livre All Rights Reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except under the terms of the Copyright, Designs and Patents Act 1988 or under the terms of a licence issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road, London W1T 4LP, UK, without the permission in writing of the Publisher. Requests to the Publisher should be addressed to the Permissions Department, John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex PO19 8SQ, England, or emailed to [email protected], or faxed to (+44) 1243 770571. This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is sold on the understanding that the Publisher is not engaged in rendering professional services. If professional advice or other expert assistance is required, the services of a competent professional should be sought. Other Wiley Editorial Offices John Wiley & Sons Inc., 111 River Street, Hoboken, NJ 07030, USA Jossey-Bass, 989 Market Street, San Francisco, CA 94103-1741, USA Wiley-VCH Verlag GmbH, Boschstr. 12, D-69469 Weinheim, Germany John Wiley & Sons Australia Ltd, 33 Park Road, Milton, Queensland 4064, Australia John Wiley & Sons (Asia) Pte Ltd, 2 Clementi Loop #02-01, Jin Xing Distripark, Singapore 129809 John Wiley & Sons Canada Ltd, 6045 Freemont Blvd, Mississauga, Ontario, L5R 4JE Canada Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books. Anniversary Logo Design: Richard J. Pacifico Library of Congress Cataloging in Publication Data Rouessac, Francis. [Analyse chimique. English] Chemical analysis : modern instrumentation and methods and techniques / Francis Rouessac and Annick Rouessac ; translated by Steve Brooks and Francis and Annick Rouessac. — 2nd ed. p. cm. Includes bibliographical references and index. ISBN 978-0-470-85902-5 (cloth : alk. paper) — ISBN 978-0-470-85903-2 (pbk. : alk. paper) 1. Instrumental analysis. I. Rouessac, Annick. II. Title. QD79.I5R6813 2007 543—dc22 2006036196 British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library ISBN 978-0-470-85902-5 (HB) ISBN 978-0-470-85903-2 (PB) 1 1 Typeset in 10 /2/12 /2pt Times by Integra Software Services Pvt. Ltd, Pondicherry, India Printed and bound in Great Britain by Antony Rowe Ltd, Chippenham, Wiltshire This book is printed on acid-free paper responsibly manufactured from sustainable forestry in which at least two trees are planted for each one used for paper production. Contents Foreword to the first English edition xiii Preface to the first English edition xv Preface to second edition xvii Acknowledgments xix Introduction xxi PART 1 SEPARATION METHODS 1 1 General aspects of chromatography 3 1.1 General concepts of analytical chromatography 3 1.2 The chromatogram 6 1.3 Gaussian-shaped elution peaks 7 1.4 The plate theory 9 1.5 Nernst partition coefficient (K)11 1.6 Column efficiency 12 1.7 Retention parameters 14 1.8 Separation (or selectivity) factor between two solutes 17 1.9 Resolution factor between two peaks 17 1.10 The rate theory of chromatography 19 1.11 Optimization of a chromatographic analysis 22 1.12 Classification of chromatographic techniques 24 Problems 27 2 Gas chromatography 31 2.1 Components of a GC installation 31 2.2 Carrier gas and flow regulation 33 2.3 Sample introduction and the injection chamber 34 2.4 Thermostatically controlled oven 39 2.5 Columns 39 2.6 Stationary phases 41 2.7 Principal gas chromatographic detectors 46 2.8 Detectors providing structural data 50 2.9 Fast chromatography 52 2.10 Multi-dimensional chromatography 53 2.11 Retention indexes and stationary phase constants 54 Problems 58 vi CONTENTS 3 High-performance liquid chromatography 63 3.1 The beginnings of HPLC 63 3.2 General concept of an HPLC system 64 3.3 Pumps and gradient elution 65 3.4 Injectors 68 3.5 Columns 68 3.6 Stationary phases 70 3.7 Chiral chromatography 75 3.8 Mobile phases 76 3.9 Paired-ion chromatography 78 3.10 Hydrophobic interaction chromatography 80 3.11 Principal detectors 80 3.12 Evolution and applications of HPLC 87 Problems 89 4 Ion chromatography 93 4.1 Basics of ion chromatography 93 4.2 Stationary phases 96 4.3 Mobile phases 98 4.4 Conductivity detectors 100 4.5 Ion suppressors 101 4.6 Principle and basic relationship 104 4.7 Areas of the peaks and data treatment software 105 4.8 External standard method 105 4.9 Internal standard method 107 4.10 Internal normalization method 110 Problems 112 5 Thin layer chromatography 117 5.1 Principle of TLC 117 5.2 Characteristics of TLC 120 5.3 Stationary phases 121 5.4 Separation and retention parameters 122 5.5 Quantitative TLC 123 Problems 125 6 Supercritical fluid chromatography 127 6.1 Supercritical fluids: a reminder 127 6.2 Supercritical fluids as mobile phases 129 6.3 Instrumentation in SFC 130 6.4 Comparison of SFC with HPLC and GC 131 6.5 SFC in chromatographic techniques 133 7 Size exclusion chromatography 135 7.1 Principle of SEC 135 7.2 Stationary and mobile phases 137 7.3 Calibration curves 138 7.4 Instrumentation 139 7.5 Applications of SEC 140 Problems 143 CONTENTS vii 8 Capillary electrophoresis and electrochromatography 145 8.1 From zone electrophoresis to capillary electrophoresis 145 8.2 Electrophoretic mobility and electro-osmotic flow 148 8.3 Instrumentation 152 8.4 Electrophoretic techniques 155 8.5 Performance of CE 157 8.6 Capillary electrochromatography 159 Problems 161 PART 2 SPECTROSCOPIC METHODS 165 9 Ultraviolet and visible absorption spectroscopy 167 9.1 The UV/Vis spectral region and the origin of the absorptions 167 9.2 The UV/Vis spectrum 169 9.3 Electronic transitions of organic compounds 171 9.4 Chromophore groups 173 9.5 Solvent effects: solvatochromism 174 9.6 Fieser–Woodward rules 176 9.7 Instrumentation in the UV/Visible 178 9.8 UV/Vis spectrophotometers 181 9.9 Quantitative analysis: laws of molecular absorption 186 9.10 Methods in quantitative analysis 190 9.11 Analysis of a single analyte and purity control 192 9.12 Multicomponent analysis (MCA) 193 9.13 Methods of baseline correction 196 9.14 Relative error distribution due to instruments 198 9.15 Derivative spectrometry 200 9.16 Visual colorimetry by transmission or reflection 202 Problems 203 10 Infrared spectroscopy 207 10.1 The origin of light absorption in the infrared 207 10.2 Absorptions in the infrared 208 10.3 Rotational–vibrational bands in the mid-IR 208 10.4 Simplified model for vibrational interactions 210 10.5 Real compounds 212 10.6 Characteristic bands for organic compounds 212 10.7 Infrared spectrometers and analysers 216 10.8 Sources and detectors used in the mid-IR 221 10.9 Sample analysis techniques 225 10.10 Chemical imaging spectroscopy in the infrared 230 10.11 Archiving spectra 232 10.12 Comparison of spectra 233 10.13 Quantitative analysis 234 Problems 238 viii CONTENTS 11 Fluorimetry and chemiluminescence 241 11.1 Fluorescence and phosphorescence 241 11.2 The origin of fluorescence 243 11.3 Relationship between fluorescence and concentration 245 11.4 Rayleigh scattering and Raman bands 247 11.5 Instrumentation 249 11.6 Applications 253 11.7 Time-resolved fluorimetry 255 11.8 Chemiluminescence 256 Problems 259 12 X-ray fluorescence spectrometry 263 12.1 Basic principles 263 12.2 The X-ray fluorescence spectrum 264 12.3 Excitation modes of elements in X-ray fluorescence 266 12.4 Detection of X-rays 271 12.5 Different types of instruments 273 12.6 Sample preparation 277 12.7 X-ray absorption – X-ray densimetry 278 12.8 Quantitative analysis by X-ray fluorescence 279 12.9 Applications of X-ray fluorescence 279 Problems 281 13 Atomic absorption and flame emission spectroscopy 285 13.1 The effect of temperature upon an element 285 13.2 Applications to modern instruments 288 13.3 Atomic absorption versus flame emission 288 13.4 Measurements by AAS or by FES 290 13.5 Basic instrumentation for AAS 291 13.6 Flame photometers 297 13.7 Correction of interfering absorptions 298 13.8 Physical and chemical interferences 302 13.9 Sensitivity and detection limits in AAS 304 Problems 305 14 Atomic emission spectroscopy 309 14.1 Optical emission spectroscopy (OES) 309 14.2 Principle of atomic emission analysis 310 14.3 Dissociation of the sample into atoms or ions 311 14.4 Dispersive
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