Introduction to Atomic Absorption Spectrometer - PowerPoint

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					Varian Technologies korea., Ltd.
        Introduction to
Atomic Absorption Spectrometer



           조   창   래
Varian Australia, Melbourne




                              1
                   AA280 Configurations Available

                                 AA280 Zeeman or D2 (graphite
AA280 FS (Flame)
                                 furnace)
                                            ICP-MS
           200


           150
Price $k




                                ICP-OES
           100


           80
                                          GF-AAS


           40             Flame AA



                 100%   0.1 %     ppm        ppb     ppt   ppq
          광학 스펙트럼의 기본형


   태양광선               프리즘




 Sir Isaac Newton 이 1600년말 스펙트럼 발견
               Fraunhofer


 1802 Wollaston 이 태양광선에서 검은 spectrum발견
 Fraunhofer 정밀분석




 회색선의 요인은 대기중에서 태양의 특정 파장이 흡수됨
            Kirchhoff & Bunsen 공동실험 (1)

     광원
           렌즈

                     렌즈



금속끝에 염첨가                                  백색종이
                버너



                                          흡수선

                                프리즘
              흡수 vs 방출

                                    Fraunhofer
                                    흡수선



  Cu     Ba   Na           K
                                    방출선




190 nm                         900 nm


               원소의 정성분석
                           주기율표

H                                                        He
              Flame Only
Li Be                                   B C N O F        Ne
Na Mg         Flame & Furnace           Al Si P   S   Cl Ar
K Ca Sc Ti V     Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
Rb Sr Y    Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I      Xe
Cs Ba La Hf Ta W Re Os Ir       Pt Au Hg Tl Pb Bi Po At Rn
Fr Ra Ac
             Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

             Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr
Gamma rays                                     Radio waves
             X rays                    Microwaves
                       UV   Infrared



      1nm        100nm           1mm         1m



                      Visible Region


       430            500     560      600    650      750 nm
바닥상태 원자




          Orbitals
          Neutrons
          Protons
          Electrons
           원자의 에너지흡수



             최 외각 전자

                       들뜬원자의
                 h     상태
           에너지
바닥상태의 원자    흡수
            Energy Level Diagram
            전자에너지 이동
                                   E4

                                   E3
                                   E2
                                   E1




                                   Eo
1   2       3    4   5   6

          공명선은 바닥상태 (Eo)로부터 시작
                     원자흡수과정

                               에너지 전이
                                                  E3

                                                  E2
태양광선     대기흡수
                                                  E1




                                                  Eo
 3 2   1     4        1      2    3   4
 공명선은 바닥상태로부터 유래
  Energy Level Diagram for Pb

                                           E4

                                           E3
                                           E2
                                           E1




                                           Eo
202.2      217.0      261.4        283.3
        Wavelength in Nanometers
             Absorption Energy Diagram
                (Few Lines/Element)

                   Excitation
                           E    이온화



                            E3
                            E2
                                 }   들뜬상태
Energy




                           E1          c
                                       b
         a     b   c   d
                                       a
                            Eo       바닥상태
             Emission Energy Diagram
              (Many Lines/Element)

                  방출
                          E   이온화



                          E3
                          E2
                               }   들뜬상태
Energy




                          E1         c
                                     b
         a    b   c   d
                                     a
                          Eo       바닥상태
                     원자흡수 과정




                Io       It




Resonance
Non-resonance                  Resonance
Fill Gas
              Beer-Lambert 흡수치 계산법


                     Io
         A = log (        ) = abc
                     It
                  Ac
Where:

A = 흡광도                       a = 흡수계수
Io = 입사광 세기                   b = 길이
It = 투과광 세기                   c = 농도
    % 투과량 vs 흡광치




투           과   흡       수

    100 %           0
     10 %           1
      1%            2
    0.1 %           3
    Beer-Lambert 법칙



    이론 선
    A = abc
A
b                    실제선
s
                  A  abc



           Conc
             Reasons for Non-linearity
                               for Calibration Graphs



   Unabsorbed radiation, stray light
   Hollow cathode lamp line width broadening
   Monochromator slit is too wide
   Disproportionate decomposition of
    molecular species
Slit Width
Single Beam Configuration
Double Beam Configuration
The First AAS
  Fast Sequential Lamp Selection


                  High Speed
                 Monochromator


                                    HC Lamps
                              D2
                             Lamp
Reference Beam




   Burner
                 Motorised
                  Mirror
                Atomizers


 Flame atomization

 Graphite furnace atomization

 Vapor generation
Flame Atomization
                    Flame Types


 Air - C2H2 flame / 2125 ~ 2400(oC)
  : Cu, Pb, K, Na, etc.
 (Air) - N2O - flame / 2600 ~ 2800(oC)
 : Al, Si, W
 Both : As, Ca, Cr, Mg, Os, Se, Sr
 Fuel - C2H2
 Oxidant - Air in Air/C2H2
             N2O in N2O/C2H2
 Fuel rich flame = Reductant flame
 Fuel thin flame = Oxidant flame
                Flame Atomization


   1) Nebulization   M+ + A- (Solution)
   2) Desolvation    M+ + A- (Aerosol)
   3) Liquefation    MA      (Solid)
   4) Vaporization   MA      (Liquid - Gas)
   5) Atomization    M0 + A0 (Gas)
   6) Excitation     M*      (Gas)
   7) Ionization     M+ + e- (Gas)
Flame Atomizer - Burner
Spraychamber Kits
Nebulizer Assembly
Nebulization
Sample Introduction Pump System
         SIPS - 10 / 20
                                What is SIPS?


 SIPS-20 dual pump system
  provides additional benefits:

   On-line addition of chemical
     modifiers e.g.
      Ionization suppressants
      Internal standard correction


    On-line Standard Additions
     calibration from one standard

    On-line preparation of
     analytical spikes from 1 Std.
                 Schematic of SIPS-10 Operation

 Sample is pumped to a Tee
                                                                 to nebulizer
 Tee is also connected to diluent
and outlet flows to nebulizer

 Stop pump, only diluent is
aspirated through nebulizer                                      air inlet
                                                   continuous
 Start pump, sample is pumped                            flow
and mixed with diluent as it flows to    sample                       mariotte
the nebulizer                              or                         bottle
                                        standard
 Pump speed controls dilution                              diluent
ratio applied - balance of nebulizer
flow made-up of diluent

 Typical dilution error < 2 %
                   Schematic of SIPS-20 Operation

 SIPS-20 with 2 pumps allows
sample to be introduced with
another solution e.g. standard,
modifier, internal standard

 Proportion of solution added to
sample is controlled by relative pup
speed

 Can “spike” sample with varying
amounts of modifier – providing new
capabilities e.g. on-line standards
additions, internal standarization

 Sample pump speed is reduced,
compared with SIPS-10 operation,
to prevent flooding of nebulizer
Graphite Furnace Atomizer
Typical Graphical Representation from ATOM
                 Steps in Running SRM Wizard

    Examine the
    results
    (30 to 40 mins.
    later)


      Shape
      maximum is
      the optimum
      setting




Pressing OK creates a method with the optimum settings
               Enhanced Tube Lifetimes –
                            Precision Comparison




Signal graphics for sample at 400th & 4,000th firing
Based on 10 replicates per sample for a 30ug/L Cu Ave
precision < 0.5% RSD
               Furnace Atomization


   1) Drying
   2) Ashing(Pyrolysis)
   3) Cool down(optional)
   4) Atomization
   5) Clean out
   6) Cool down
                      Workhead


    Water Cooling      Gas Out                   Sealed
                                                 Quartz
                                                 Window

Optical
 Path




          Gas Inlet
                                 Flexible Seal
      비불꽃 원자화 과정



                           Clean
                            Out
                 Atomize

                                          T
                                   Cool   E
       Ash                                M
                                   Down
                                          P
Dry



             T I M E
                  Interferences




   1) Spectral interference
   2) Chemical interference
   3) Ionization interference
   4) Matrix interference
   5) Non-specific interference
               Chemical Modifier



     Chemical Modifiers for Specific Elements in GFAAS


Analyte        Modifier         Effect


As             Ni              Permits a higher ashing temperature
               Pd              and enhances the signal

Cd             H3PO4+          Conversion to less volatile phosphate
                Mg(NO3)2       which atomizes at a higher temperature
               NH4H2PO4
               Pd


Pb             H3PO4+          Permits a higher ashing temperature
                Mg(NO3)2       and stabilizes the signal
               NH4H2PO4
               EDTA
               citrate
               oxalate
                    Chemical Modifier




     Chemical Modifiers for Specific Matrices in GFAAS


Interfering    Analyte      Modifier       Effect
Species

Blood          Pb           Triton X-100   Dispersing Agent-
                                           Facilitates dispensing

Serum &        Al, Cr, Mn   Dilute
Blood                       Triton X-100
Vapor Generation Atomizer
- As, Se, Sn, Sb, Te, Bi, Hg
                 Light Sources



   Hollow cathode lamps - HCL
   Multi-element lamps
   Ultra lamps
   Electrodeless discharge lamps - EDL
   Deuterium lamp - D2
               Hollow Cathode Lamp Process




 Sputtering

 Collision and Exitation

 Emission and Stabilization
           Background Correction


 Deuterium technique
 Smith - Heiftje technique
 Zeeman technique:
  DC Zeeman design
  AC Zeeman design
  Longitudinal Zeeman Design
  Transverse Zeeman Design
             D2 Background Correction



                  Deuterium Lamp Operation




I
    1
n
t 0.8
e
  0.6
n
s 0.4   Normal Range
                                Lower HCL mA
i        190-
         190-300 nm
  0.2                             300-
                                  300-425 nm
t                                                         No D2
                                                       425-
                                                       425-900 nm
y 0
    190 210 230 250 270 290 310 330 350 370 390 410 430 450 470 490

                               Wavelength
Smith - Heiftje Technique
Zeeman Technique
Longitudinal Zeeman Design
Transverse Zeeman Design
     Monochromator



Czerny - Turner Type


Ebert - Fastie Monochromator


Littrow Monochromator Design
Czerny - Turner Type
Ebert - Fastie Monochromator
Littrow Monochromator Design
Gratings
                 Detectors


 Photomultiplier tube(PMT)
           불꽃 vs 비 불꽃 AAS

Criteria        Flame   Furnace
분석원소            67      48
감 도             ppm-%   ppt-ppb
정밀도             good    fair
간   섭           few     many
속   도           rapid   slow
사용하기            easy    more complex
불꽃에대한위험         yes     no
자동화             yes     yes
분석비용            low     medium
          불꽃 vs 비 불꽃 검출한계 비교


Element        Flame (ppb)    Furnace(ppb)*
 Ag               3             0.035
 As             450             0.25
 Bi              50             0.45
 Cd               3             0.01
 Cr               9             0.075
 Pb              15             0.2
 Zn               1.5           0.0075
  *Note: 20 L Volume & D2 Peak Height Abs
                        불꽃 vs 비 불꽃 감도


                          100 g/L Pb @ 217.0 nm

0.936
                                            비불꽃 시그날
                                            for 10 L
  Absorbance




               불꽃 시그날




0.004
                  Terminology


   1) Sensitivity
   2) Detection limit
   3) Quantitation limit
   4) Accuracy
   5) Precision
   6) Standard Deviation
SpectrAA 50/55
SpectrAA 220FS
   New SPS2 & SPS3 Flame Autosamplers

 SPS 2 & SPS 3 Autosamplers
Schematic of Traveling Rinse


   Probe

               Housing for Traveling Rinse

                        Inlet for rinse solution
                              (from pump)


                       Outlet to waste
    D.L Using UltrAA Lamps



                                    Conventional
                                                   Ultra Lamp
Element   Wavelength   Slit Width   lamp
                                                   D.L
                                    D.L

  As      193.7nm         0.5           1.4          0.25

  Pb      283.3nm         0.5           0.8          0.20

  Se      196.0nm         1.0           1.1          0.30
SpectrAA 220Z
What is ICP – AES ?
AAS 와 ICP-AES 비교
Sequential 과 Simultaneous 비교
What is ICP – MS ?
                                   Varian ICP-MS
                                  Design Highlights
90 degree ion mirror for the                     Peltier cooled spraychamber
highest sensitivity and low                       and low sample uptake for low
background                                        oxides and reduced sample
                                                  usage
High speed, low
noise/background quadrupole                       Optimized interface for high
with curved fringe rods                           transmission, good matrix
                                                  tolerance and low oxides
Robust, high efficiency, solid
state 27MHz balanced plasma                       9 orders, all digital detector for
system                                            easy setup and operation
(no torch shield required)
  Varian ICP-MS
개선된 Ion Optics Design

              High efficiency
                 >1000 Mcps/ppm in high sensitivity
                  mode

              Low background
                 90 degree ion mirror
                 Double off axis quad

              Low oxides
                 <1% CeO
                           Comparison of Techniques
                          ICP-MS           ICP-OES       FAAS         GFAAS
Detection Limits            Excellent         good         good       Excellent
Productivity                Excellent      very good       good           low
LDR                             108             105          103          102
Precision                     1-3%           0.3-2%       0.1-1%        1-5%
Spectral interference          few          common      almost none    very few
Chemical interference       moderate           few         many         many
Ionization                  minimal         minimal        some        minimal
Mass Effects            high on low mass      none         none          none
Isotopes                        yes           none         none          none
Dissolved solids            0.1-0.4%         2-25%        0.5-3%      up to 20%
No. of elements                 75              73           68            50
Sample usage                   low          medium         high        very low
Semi-quantitative               yes             yes          no            no
Isotope analysis                yes             no           no            no
Routine operation              easy            easy         easy         easy
Method development           skill req      skill req       easy       skill req
Running costs                  high           high          low        medium
Capital costs               very high         high          low        medium
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posted:10/9/2012
language:English
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