Handbook of Inductively Coupled Plasma Spectrometry

Transcription

1 Handbook of Inductively Coupled Plasma Spectrometry

2 Handbook of Inductively Coupled Plasma Spectrometry Second Edition MICHAEL THOMPSON, BSc, PhD, ARCS, CChem., FRSC Department of Chemistry Birkbeck College University of London J. NICHOLAS WALSH, BSc, PhD Department of Geology Royal Holloway and Bedford New College University of London with additional invited chapters from S.J. Walton and G.E.M. Hall Blackie Glasgow and London Published in the USA by Chapman and Hall New York

3 Blackie and Son Ltd Bishopbriggs, Glasgow G64 2NZ 7 Leicester Place, London WC2H 7BP Published in the USA by Chapman and Hall a division of Routledge, Chapman and Hall, Inc. 29 West 35th Street, New York, NY Blackie & Son Ltd Softcover reprint of the hardcover 1st edition 1989 First published 1983 Reprinted 1984, 1985, 1986 This edition 1989 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, recording or otherwise, without prior permission of the Publishers. British Library Cataloguing in Publication Data Thompson, Michael, Handbook of inductively coupled plasma spectrometry. -2nd ed. I. Chemical analysis. Inductively coupled plasma emission spectroscopy I. Title II. Walsh, J. Nicholas (John Nicholas) 543'.0858 ISBN-13: e-isbn: DOl: / Library of Congress Cataloging-in-Publication Data Thompson, Michael, Ph.D. Handbook of inductively coupled plasma spectrometry. "A complete revision with additional invited chapters from S.J. Walton and G.E.M. Hall." Bibliography: p. Includes index. \. Plasma spectroscopy. I. Walsh, J.N. (John Nicholas) II. Title. QD96.P62T ' Phototypesetting by Thomson Press (India) Limited, New Delhi

4 Preface The first edition of our Handbook was written in In the preface to the first edition we noted the rapid development of inductively coupled plasma atomic emission spectrometry and its considerable potential for elemental analysis. The intervening five years have seen a substantial growth in ICP applications; much has happened and this is an appropriate time to present a revised edition. The basic approach of the book remains the same. This is a handbook, addressed to the user of the technique who seeks direct, practical advice. A concise summary of the technique is attempted. Detailed, theoretical treatment of the background to the method is not covered. We have, however, thoroughly revised much of the text, and new chapters have been added. These reflect the changes and progress in recent years. We are grateful to Mr Stephen Walton, Dr Gwendy Hall and London and Scandinavian Metallurgical Co. Ltd for their contributions. Chapter 3 (Instrumentation) has been rewritten by Mr Walton, the new Chapter on ICP-mass spectrometry has been written by Dr Hall, and London and Scandinavian provided much of the information for the chapter on metals analysis by ICP-AES. These chapters have been integrated into the book, and a conscious effort has been made to retain the unity of style within the book. New material has been added elsewhere in the book, archaeological materials are considered, pre concentration methods and chemometrics covered more fully. Other sections of the Handbook have stood the test of time and remain much as before. The chapter on 'ICP and the future' has been omitted-the future is with us now. It is our intention that this Handbook will provide an introduction to ICP spectrometry for those using the technique in routine analytical applications. It is designed to present general background information on ICP-AES analysis for those who need to familiarize themselves with the reality and the potential of the technique. The book brings together a systematic collection of information on the background and operation of the ICP. It also provides detailed methods for those involved in routine analysis. In our revision of the book we have tried to expand its usefulness to cover a greater range of areas of application. We hope that it will be both a laboratory manual and a general reference text. We should like to acknowledge our considerable debt to all those friends and colleagues who have contributed to this book, directly or v

5 vi PREFACE indirectly, by way of material assistance, collaboration, technical discussion or simply tolerating us while we were writing. One of us (JNW) is indebted to the Natural Environment Research Council, the University of London and Philips for financial support, and to Jan Barker and Alison Warren for their support and assistance.

6 Contents 1 Introduction Preliminary-purpose and scope of book The ICP as a spectroscopic source Applications of the ICP Simplicity of the ICP technique The literature of ICP-AES Historic development of ICP spectrometry Background to quantitative ICP analysis Sample introduction (nebulization) Sample excitation system Analysis and quantification of emission spectrum Range of determinable elements in geological materials 14 2 Analytical characteristics Introduction Simultaneous analysis Compromise operating conditions Sequential analysis ICP system Detection limits Calibration range oflcp-aes Interferences Spectral overlaps Stray light interference Matrix effect Precision and accuracy Chemometric improvements to data quality Experimental considerations Solution volumes and sample weights Number of elements determined in liquid samples Number of elements determined in solid samples The injection of organic liquids into an ICP 40 3 Instrumentation for ICP-AES Introduction Spectrometers General requirements Simultaneous spectrometers Sequential spectrometers Combined simultaneous/sequential spectrometers Plasma torches Nomenclature The Greenfield torch The Fassel torch The Minitorch Torch maintenance Nebulizer systems Introduction Concentric pneumatic nebulizers 66 vii

7 viii CONTENTS Cross-flow nebulizers Babington-type nebulizers Frit-type nebulizers Ultrasonic nebulizers Direct nebulization Spray chambers Radiofrequency generators and source Electronics, computers and software Software requirements Trends Fourier transform spectrometers ICP-atomic fluorescence spectrometry Direct current plasmas (DCP) Microwave plasmas (MIP) Choice of an ICP system ICP-AES in relation to AAS ICP-AES and X-ray fluorescence ICP-AES and DCP emission spectrometry ICP-AES and ICP-mass spectrometry ICP-AES and other excitation methods 9 I Evaluation of an ICP-AES system 92 4 Silicate rock analysis Dissolution methods for silicates Introduction Fusion dissolution methods Hydrofluoric acid dissolution methods-open evaporation Hydrofluoric acid dissolution methods-closed digestion Instrument calibration Major element determinations Trace element analysis Rare earth element determinations Introduction Dissolution procedure REE separation REE spectral lines Evaluation of results Multielement applications of ICPS in applied geochemistry The nature and evolution of applied geochemistry Introduction General aspects of applied geochemical analysis Analytical requirements in applied geochemistry Analytical quality control procedures ICP instrumentation in relation to the requirements of applied geochemistry Introduction Translational interference effects Rotational interference effects 14 I Other instrumental constraints in multielement analysis Decomposition procedures in applied geochemical analysis Introduction General aspects of large-batch analysis Decomposition with nitric acid and perchloric acid Decomposition with hydrofluoric acid, nitric acid and perchloric acid (test tube version) 156

8 CONTENTS ~ 6 Gas phase sample injection The development of gas phase injection methods Methodology of the hydride injection system Equipment Operating conditions Performance of the hydride generation/icp system Interference effects and their avoidance Arsenic speciation methods Applications of the hydride injection system General introduction Traces of arsenic, antimony and bismuth in soils and sediments Traces of arsenic, antimony and bismuth in plant materials Trace concentrations of selenium in soils and sediments The determination of trace concentrations of arsenic, antimony, bismuth, selenium and tellurium in waters The determination of tin in rock, soils and sediments Injection methods for solid samples Introduction to solid sample injection methods Sample injection following electrothermal vaporization Direct sample injection from a graphite rod Discrete sample injection by means of laser ablation General introduction The Lasertrace system The LMAIO laser-icp microprobe system Nebulization of slurries Water analysis by ICP-AES Introduction 20 I 8.2 General aspects of water analysis Sampling Filtration Storage Stabilization Avoidance of contamination Direct water analysis by ICP-AES Pneumatic nebulizers Alternative nebulizers Gas phase injection Electrothermal vaporization and other discrete methods Water analysis with preconcentration Evaporation methods Mixed-bed ion exchange method Selective ion exchange methods Solvent extraction methods A chelation-solvent extraction procedure Coprecipitation methods The analysis of environmental materials by ICP-AES Introduction 2 I Air analysis Volatile contaminants Particle contaminants Sewage sludge 219

9 x CONTENTS 9.4 Domestic dust, road dust and industrial dust Domestic dusts Road dusts Industrial dusts Domestic and industrial refuse The analysis of animal and plant tissues General introduction Sample decomposition of biological materials Destruction of organic matter in plant and animal tissue with perchloric acid-nitric acid mixtures The analysis of archaeological materials by ICP-AES Introduction Archaeological materials Analysis of flints Pottery and clay analysis Analysis of bricks, tiles, glazes, etc Analysis of metals Analysis of slags and ores Inductively coupled plasma mass spectrometry 238 ILl Instrumentation Optimization Interferences Spectral interferences Non-spectral interferences Calibration strategies External Isotope dilution Standard additions 251 1l.5 Applications of ICP-MS with sample introduction by nebulization Elemental analysis of solubilized geological samples Isotope ratio measurements Analysis of waters Other modes of sample introduction Electrothermal vaporization (ETV) Direct sample insertion device (DSID) Laser ablation of solids Arc nebulization (solid sampling) Slurry nebulization (solid sampling) Future directions Analysis of metals by ICP-AES Introduction Instrument calibration Internal standards Sample preparation and dissolution Analysis of iron and steel Spectral lines Sample dissolution Analysis of other metals Virgin aluminium program Titanium-boron-aluminium program Zirconium-aluminium program Chromium program Chrome carbon program 281

10 CONTENTS Nickel-cobalt ailoy program Ferro-boron program Nickel-boron program Copper base program Stellite program I Manganese tablet program I 2 Ferro-aluminium program Appendix 1 Safety Appendix 2 Manufacturers of ICP systems and accessories References Index xi