Analysis of pure lead and lead alloys for the automotive leadacid battery industry by inductively coupled argon plasma emission spectroscopy

1 J P Matousek, B J Orr, and M Selby, Appl Spectrosc 38, 231 (1984) J P Nogier, Communication SITEF, Toulouse (1987) T Fuyuki, K Ohtoshi, T Saito, and H Matsunami, Proc 8th Intern Symp Plasma Chem., Tokyo, 1,519 (1987) L G Piper and W T Rawlins, J Phys Chem 90, 320 (1986) D A Parkes, L F Keyser, and F Kaufman, Astrophys J 149, 217 (1967) R Avni and J D Winefordner, Spectrochim Acta 30B, 281 (1975) S R Goode, N P Buddin, B Chambers, K W Baughman, and J P Deavor, Spectrochim Acta 40B, 317 (1985) P S Moussounda, P Ranson, and J M Mermet, Spectrochim Acta 40B, 641 (1985) K Tanabe, H Haraguchi, and K Fuwa, Spectrochim Acta 38B, 49 (1983) 10 K Fallgatter, V Svoboda, and J D Winefordner, Appl Spectrosc 25, 347 (1971) 11 J Hubert, M Moisan, and A Ricard, Spectrochim Acta 33B, (1979) 12 A Lifshitz, G B Skinner, and D R Wood, J Chem Phys 70, 5607 (1979) 13 A Bouvier, S Abed, B Charlet, and A Bouvier, J Phys Coll., C7., 40, 197 (1979) 14 J M Workman, P G Brown, D C Miller, C J Seliskar, and J A Caruso, Appl Spectrosc 40, 857 (1986) 15 M H Abdallah and J M Mermet, Spectrochim Acta 37B, 391 (1982) 16 J M Workman, P A Fleitz, H B Fannin, J A Caruso, and C J Seliskar, Appl Spectrosc 42, 96 (1988) 17 C Dupret, B Vidal, and P Goudmand, Rev Phys Appl 5, 337 (1970) 18 J Terrien, N.P.L Symposium No 11, Interferometry 435, Teddington (1959) 19 G H Dieke and H M Crosswhite, J Quant Spectrosc Radiat Transfer 2, 97 (1962) 20 S De Jaegere, M Willems, and C Vinckier, J Phys Chem 86, 3569 (1982) 21 M Capitelli and E Molinari, Topics in Current Chemistry 90, 59 (1980) 22 A T Zander and G M Hieftje, Appl Spectrosc 35, 357 (1981) 23 F Etile, Th~se, Universit~ Pierre et Marie Curie, Paris (1979) 24 T Carrington and H P Broida, J Molec Spectrosc 2, 273 (1958) 25 D E Rapakoulias and D E Gerassimou, Proc 8th Intern Symp Plasma Chem., Tokyo, 3, 1967 (1987) 26 A M Diamy, N GonzalezFlesca, and J C Legrand, Spectrochim Acta 41B, 317 (1986) Analysis of Pure Lead and Lead Alloys for the Automotive Lead/Acid Battery Industry by Inductively Coupled Argon Plasma Emission Spectroscopy T J SCHMITT,* J P WALTERS, and D A WYNNt Johnson Controls, Inc., Corporate Applied Research Center, 5757 N Green Bay Avenue, Milwaukee, Wisconsin 53209 (T.J.S., D.A.W.); and Department of Chemistry, St Olaf College, Northfield, Minnesota 55057 (J.P.W.) Pure lead and lead alloy dissolution procedures suitable for elemental determinations by inductively coupled argon spectroscopy are described The group of lead types investigated consisted of pure lead, Pb-Sb alloys, Pb-Ca-AI alloys, and Pb-Ca-Sn-AI alloys Major alloy concentrations range up to 10% Sb, 2% Sn, 0.2% Ca, and 0.1% AI Trace impurities from 0.5 to 10 ppm are determined in pure lead and in several lead alloys Major and trace element determinations are routinely performed simultaneously with the use of five to seven matrix-matched standards for each alloy type Accuracy and precision data for certified and internal reference materials are reported Chemical, spectral, and metallurgical interferences are also discussed Index Headings: Lead; Pure lead; Lead alloys; Dissolution procedures; Inductively coupled argon plasma; ICP INTRODUCTION T h e purpose of this work is to d e m o n s t r a t e t h a t inductively coupled argon plasma emission spectroscopy (ICP) is a very precise and accurate tool for the analysis of pure lead and lead alloys Inductively coupled argon plasma emission spectroscopy is an ideal instrumental m e t h o d of analysis for lead as a result of the argon plasma stability, the absence of major spectral interferences for Received 11 November 1988 * Present address: Compunetics Inc., 2000 Eldo Road, Monroeville, PA 15146 t Author to whom correspondence should be sent Volume 43, Number 4, 1989 the lead alloys analyzed, and simultaneous multielement analysis capability Major alloy elements and trace impurities in lead can be routinely d e t e r m i n e d without any special instrument, standard, or sample preparation considerations T h e lead types of interest in this work are pure lead, calcium-aluminum alloys, calcium-tin-alum i n u m alloys, and a n t i m o n y alloys T o t a l weight percent of lead in these alloys never drops below ninety in routine analyses T h e accurate analysis of pure lead and lead alloys is very i m p o r t a n t in the lead/acid b a t t e r y industry Trace impurities as well as major alloy c o m p o n e n t s affect the overall performance of the b a t t e r y system Several elem e n t s (such as Te, As, and Se) at trace levels ( < ppm) c a u s e severe g a s s i n g p r o b l e m s w h e n b a t t e r i e s are charged 1,2 Gassing is the generation of hydrogen and oxygen from the electrochemical dissociation of water T h e presence of a gassing element is t h o u g h t to lower the hydrogen overcharge potential by several mechanisms Excessive gassing depletes the electrolyte, shortens b a t t e r y life, and causes battery case bulging Major alloy concentrations are i m p o r t a n t for proper b a t t e r y grid strength, corrosion resistance, and proper b a t t e r y grid manufacturing B a t t e r y grids provide the mechanical s u p p o r t and electrical current p a t h in b o t h the negative and positive plates of the battery All of these factors affect b a t t e r y life and performance 0003-7028/89/4304-068752.00/0 © 1989 Society for Applied Spectroscopy APPLIED SPECTROSCOPY 887 TABLE Description of ICP instrument Jobin Yvon 1.0-m PaschenRunge JY-48P vacuum with 39 channels Thermoregulation of polychromator Modifiedso that analyte emission can be blocked from the 182.037nm and 220.353-nmexit slits Entrance is 0.020 mm and is Slits computer controlledfor background correction.Exits are 0.039 and 0.050 ram Holographic, 2550 groves/ Grating mm Dispersion First order, 0.39 nm/mm Spectral range 160-416 nm Optical path Extension tube purged with argon Mini-monochro- Instruments SA, Model H-20 mator Monochromator Hilger-Engis, Model 1000 Plasma Therm, Model 2500, Source Generator 27.12 MHz Auto impedance matching network with remote control Quartz, 135 mm Torch MAK-10 cross-flow."PerisalSample Nebulizer tic pump used (0.8 mL/ transport min) MAK-20, glass expansion Spray chamber chamber with baffle." Digital Equipment Corp Computer Processor PDP 11/03 system Disk drives Two 8-in RX02 drives Printer LA 120 Decwriter "Sherritt Gorden Mines Limited, Fort Saskatchewan, Alberta Canada T8L 2P2 Spectrometers Polychromator Arc emision spectroscopy,3,4,5 f a m e atomic absorption, 4,~,6x-ray fluorescence,7 and wet chemical methods, 4,5 have been the methods of analysis used for trace and alloy element determinations in the battery industry All of these methods are useful but have certain undesirable features Flame atomic absorption and wet chemical methods are very time-consuming when multielement analysis is needed X-ray fluorescence is useful for multielement analysis of major alloy elements but does not have the required detection limits for trace analysis Arc emission is used extensively in the industry because of the speed of analysis, solid sampling, minor and major element determinations, and minimal sample preparation However, arc emission does have inherent problems in the analysis of lead First, only the surface of the lead sample is analyzed This will yield an accurate analysis only if the sample is homogeneous Second, the lead is soft, and incorrect polishing of lead disks can cause erroneous results due to smearing of the sample surface Third, the limits of quantitation (LOQ) for some elements (such as Sb, Co, and Ni) in pure lead and lead alloys are not low enough for all applications Fourth, the lead standards which would be needed for arc emission techniques would be very difficult to prepare for the large number of elements routinely determined by ICP Solid calibration standards for arc emission analysis are not certified and are usually made by the user Solution 688 Volume 43, Number 4, 1989 TABLE II Routine operating conditions Frequency RF power Reflected power Argon outer flow Argon intermediate flow Argon carrier flow Observation height Sample pump rate Integration time: Off peak On peak Cleaning time Number of integrations (MHz) (kW) (W) (L/min) (L/min) (L/rain) (mm) (mL/min) 27.12 1.0