Marine Biogeochemistry

Method / Description ICP-AES

Generally:
Determination of the main and trace elements with atomic emission spectroscopy with inductively coupled plasma (ICP)-AES.

An atomic emission spectrometer with inductively coupled plasma contains a high frequency generator, a plasma torch, a high resolution spectrometer and a computer to control the instruments and the data output. An induction coil, fed by a high frequency generator, generates a strong, oscillating magnetic field at the IC-plasma torch (inductively, coupled). Argon is supplied to the burner, wich is lit with the help of a tesla coil. The high frequency generator with induction coil, supplies the energy for the ionization work in the plasma. The energy stands in direct relation to plasma-density and temperature. The plasma torch is connected with an atomizer (sprayer) system. The sample is transported to the plasma with the help of an argon-carrier-gas. The flowing argon gas generates a tunnel inside the plasma, where the sample is evaporated and stimulated (at high temperatures and longer residence time). The spectrometer receives the radiation from the observation zone above the live plasma zone. In the spectrometer the light is spectrally separated. The light intensities are measured sequentially (monochromator) or simultaneously (polychromator). All standards are diluted in a matrix similar to the sample-matrix.
 

1. Porewater samples

2. Gashydrat samples and other samples with lower concentration

3. Acid digestions of sediments (main elements)

4. Acid digestions of sediments (trace elements)
 

1. Porewater samples
ICP-AES:  JY 170 ULTRACE
Sprayer: Cross-Flow-sprayer
Reagents: HCl suprapur 30%
                NaCl p.a.
                NaCl-St.Solution: 163,3475g NaCl p.a./1000ml
                standard solution (in water). from Spex:

Ca

10000mg/l

K

10000mg/l

Mg

10000mg/l

Sr

1000mg/l

Mn

1000mg/l

B

1000mg/l

Ba

1000mg/l

Li

1000mg/l

Si

10000mg/l

Fe

10000mg/l

Y

10000mg/l

Standards, wavelengths, adjustments at the photomultiplier(HV) and measuring modus:

Element

Wave-
length

STD 0

STD 0

STD1

STD1

STD2

STD2

STD3

STD3

HV

Mess.-
mode

 

nm

mg/l

mmol/l

mg/l

mmol/l

mg/l

mmol/l

mg/l

mmol/l

V

 

K

766.490

0

0

100

2.558

200

5.115

500

12.79

993

sequential

Ca

317.933

0

0

100

2.495

200

4.99

500

12.48

455

simultaneous

Mg 

383.231

0

0

500

20.57

1000

41.14

2000

82.29

625

sequential

Na

330.237

 

599

 

279.5

 

559

 

559

723

sequential

B

249.773

0

0

1.00

0.0925

5.00

0.4625

10.0

0.925

783

sequential

 

 

mg/l

µmol/l

mg/l

µmol/l

mg/l

µmol/l

mg/l

µmol/l

 

 

Sr

407.771

0

0

2.00

22.83

5.00

57.06

10.0

114.1

676

simultaneous

Mn

257.610

0

0

0.1000

1.82

0.200

3.64

0.500

9.1

903

sequential

Li

670.784

0

0

0.100

14.41

0.200

28.81

0.500

72.04

993

sequential

Sil

251.611

0

0

2.00

71.21

10.0

356

20.0

712

953

sequential

Fe

238.204

0

0

0.100

1.791

0.5000

8.953

1.00

17.91

923

sequential

 

 

µg/l

nmol/l

µg/l

nmol/l

µg/l

nmol/l

µg/l

nmol/l

 

 

Ba

455.500

0

0

20.0

145.6

50.0

364.1

100

728

993

sequetial

-diluted in 100ml volumetric flask with 500µl HCl

Preparation of the sample:
On board: 3ml of the porewater sample and 30µl HCl are filled into 3ml-bottels(Zinsser), right after squeezing.
In the lab: all standards and samples are diluted in the relation 1:10 with a special solution: 3ml HCl and 1.1111ml Y-standard in 1000ml pure water.
Seawater standard (IAPSO) is measured as a control standard.

2. Gashydrat water samples or other samples with lower salinity:
ICP-AES:  JY 170 ULTRACE
Sprayer: Cross-Flow-sprayer
Reagents: HCl suprapur 30%
                NaCl p.a.
                NaCl-St.Solution: 163,3475g NaCl p.a./1000ml which is 2795mmolNa/l
                standard solution (in water). from Spex:

Ca

10000mg/l

K

10000mg/l

Mg

10000mg/l

Sr

1000mg/l

Mn

1000mg/l

B

1000mg/l

Ba

1000mg/l

Y

10000mg/l

Standards, wavelengths, adjustments at the photomultiplier(HV) and measuring modes:

Element

Wave-
length

STD0

STD0

STD1

STD1

STD2

STD2

STD3

STD3

STD4

STD4

HV

Mess.-
mode

 

nm

mg/l

µmol/l

mg/l

µmol/l

mg/l

µmol/l

mg/l

µmol/l

mg/l

µmol/l

V

 

B

249.773

0

0

0.100

9.25

0.500

46.249

2.00

184.997

5.00

462.492

903

sequential

Mn

257.610

0

0

0.0005

0.0910

0.020

0.3640

0.100

1.820

0.500

9.101

903

sequential

Ca

317.933

0

0

5.00

124.76

20.0

499.03

50.0

1247.6

10.0

2495.1

455

simultaneous

Na

330.237

0

0

 

13975

 

27950

 

559000

 

83850

903

sequential

Mg

383.231

0

0

20.0

822.88

50.0

2057.2

200

8228.8

500

20571

625

sequential

Sr

407.771

0

0

0.050

0.5706

0.200

2.2826

1.00

11.413

5.00

57.065

676

simultaneous

K

766.490

0

0

10.0

255.8

20.0

511.5

50.0

1.2788

100

2.5577

993

sequential

 

 

µg/l

nmol/l

µg/l

nmol/l

µg/l

nmol/l

µg/l

nmol/l

µg/l

nmol/l

 

 

Ba

455.500

0

0

5.00

36.409

20

145.63

200

1456.3

500

3640.9

993

sequential

-diluted in 100ml volumetric flask with 500µl HCl

Preparation of the sample:
On board: 3ml of the porewater sample and 30µl HCl are filled into 3ml-bottels(Zinsser), right after squeezing.
In the lab: all standards and samples are diluted in the relation 1:10 with a special solution: 3ml HCl and 1.1111ml Y-standard in 1000ml pure water.
Seawater standard (IAPSO) is measured as a control standard.

3. Acid digestions of sediments (main elements):
read the method of the acid digestion under: description acid-digestion
ICP-AES:  JY 170 ULTRACE

Sprayer: Cross-Flow-sprayer
Reagents: HNO3 suprapur 60%
                 standard solution(in water). from Spex:

Ca

10000mg/l

K

10000mg/l

Mg

10000mg/l

Sr

1000mg/l

Mn

1000mg/l

Li

1000mg/l

Ba

1000mg/l

Al

10000mg/l

Ti

1000mg/l

Fe 

10000mg/l

Na

10000mg/l

10000mg/l

Standards, wavelengths, adjustments at the photomultiplier(HV) and measuring modus:

Element

Wave-
length

STD0

STD1

STD2

STD3

STD4

STD5

HV

Mess.-
mode

 

nm

mg/l

mg/l

mg/l

mg/l

mg/l

mg/l

V

 

Fe

238.204

0

100

200

500

1000

50

676

simultaneous

Mn

257.610

0

1.00

2.00

10.0

50.0

 

872

simultaneous

Mg

383.231

0

50.0

100

200

500

10.0

625

sequential

Al

308.215

0

100

200

500

1000

 

455

simultaneous

Ca

317.933

0

10.0

20.0

50.0

200

 

455

simultaneous

Na

330.237

0

50.0

100

200

500

 

923

sequential

Sr

407.771

0

0.500

1.00

5.00

10.0

 

676

simultaneous

Ba

455.500

0

0.500

1.00

5.00

20.0

 

383

sequential

Li

670.784

0

0.10

0.200

0.500

1.00

 

993

sequential

K

766.490

0

25.0

50.0

200

500

 

993

sequential

Ti

334.941

0

1.00

2.00

5.00

10.0

 

583

sequential

-diluted in 100ml volumetric flask with 3ml HNO3

Preparation of the sample:
All standards and samples are diluted in the relation 1:10 with a special solution: 3ml HNO3 and 1.1111ml Y-standard in 1000ml pure water.

A sediment standard (MAG) is measured as a control standard.

4. Acid digestions of sediments (trace elements):
read the method of the acid digestion under: description acid-digestion
ICP-AES:  JY 170 ULTRACE
Sprayer: Meinhard-sprayer
Reagents: HNO3 suprapur 60%
                standard solution (in water). from Spex:

Cr

1000mg/l

Mo

1000mg/l

Ni

1000mg/l

Zn

1000mg/l

Cu

1000mg/l

V

1000mg/l

Y

10000mg/l

l
Standards, wavelengths, adjustments at the photomultiplier(HV) and measuring modus:

Element

Wave-
length

STD0

STD1

STD2

STD3

STD4

STD5

HV

Measuring-
mode

 

nm

µg/l

µg/l

µg/l

µg/l

µg/l

µg/l

V

 

Cr

284.325

0

10.0

50.0

100

500

1000

853

sequential

Mo

202.030

0

10.0

20.0

50.0

200

 

903

sequential

Ni

231.604

0

10.0

50.0

100

500

1000

993

sequential

Zn

213.856

0

10.0

50.0

100

500

 

753

sequential

Cu

324.754

0

20.0

50.0

100

500

 

993

sequential

V

290.882

0

10.0

50.0

100

500

 

853

sequential

-diluted in 100ml volumetric flask with 3ml HNO3  

Preparation of the sample:
The Y-srandard is diluted in the relation 1:10.
5ml of all standards and all samples are mixed with 50µl of the diluted Y-standard before they are measured.

A sediment standard (MAG) is measured as a control standard.

5. Detection- and quantification limits:

Element

Conz.

Pore-
water

Pore-
water

Gashydrat-
water

Gashydrat-
water

Acid digestion of sediment (main elements)

Acid digestion of sediment (main 
elements)

Acid
degestion
of
sediment
(trace
elements)

Acid
degestion
of
sediment
(trace
elements)

 

 

DL

QL

DL

QL

DL

QL

DL

QL

Ca

mg/l

2.00

6.00

0.60

2.00

0.05

0.20

 

 

Mg

mg/l

6.00

20.0

2.00

6.00

0.15

0.50

 

 

K

mg/l

4.00

12.0

2.00

6.00

0.60

2.00

 

 

Fe

mg/l

 

 

 

 

0.20

0.50

 

 

Al

mg/l

 

 

 

 

0.80

2.50

 

 

Ti

mg/l

 

 

 

 

1.50

5.00

 

 

Sr

µg/l

25.0

80.0

1.50

4.00

0.30

0.80

 

 

Ba

µg/l

6.00

20.0

0.60

2.00

3.00

10.0

 

 

Li

µg/l

25.0

80.0

 

 

2.00

6.00

 

 

Mn

µg/l

5.00

15.0

5.00

15.0

8.00

30.0

 

 

B

µg/l

40.0

150

10.0

30.0

 

 

 

 

Mo

µg/l

 

 

 

 

 

 

5.00

20.0

Zn

µg/l

 

 

 

 

 

 

6.00

20.0

Ni

µg/l

 

 

 

 

 

 

15.0

50.0

Cr

µg/l

 

 

 

 

 

 

5.00

1.0

V

µg/l

 

 

 

 

 

 

5.00

15.0

Cu

µg/l

 

 

 

 

 

 

6.00

20.0

DL=Detection limit
QL=Quantification limit