Silicon, Si

Known issues with the parameter and/or important method changes

Summary of problems with the silicon analysis at the Geochemical laboratory during 2005-2010 (in Swedish).

Method comparison from the change to optical ICP (in Swedish).

Current method of measurement (inductively coupled plasma)

Valid since January 2018
Metod: Metod: ICP-MS, SS-EN ISO 17294-2:2016
Instrument: Agilent.

Previous methods

Previous methods (inductively coupled plasma)

2016 01 - 2017 12 (implemented Maj 2016 but valid for samples from January 2016)
Method: ICP-MS, SS-EN ISO 17294-2:2005
Instrument: Agilent.

2014 01 - 2015 12
Method: ICP (inductively-coupled plasma), SS-EN ISO 11885:2009
Instrument: PerkinElmer OPTIMA 2100

Previous methods (molybdate-reactive silicon)

The forms of silicon that occur in natural waters exhibit highly variable reactivity with different analytical reagents. Our earlier method measured so-called molybdate-reactive silicon, which represents the amount of dissolved silicon.

2007 01 - 2013 12
Method: Bran & Leubbe Method G-177-96 rev. 8 (Multitest MT 19)
Instrument: Autoanalyzer 3 (upgraded Autoanalyzer II).
NB: Samples conserved with H₂SO₄.

1995-01 – 2006-12
Method: Bran & Leubbe Industrial Method No. 811-86T.
Instrument: Technicon Traacs 800.
NB: Water samples converved with HgCl₂ until 1996, and with H₂SO₄ since 1997.

1987-01 – 1994-12
Method: Standard Methods 12th Ed. 1965. Henriksen, A: Automatic Modification.
Instrument: Technicon Autoanalyzer II.
NB: Water samples converved with HgCl₂.

1971-01 – 1986-12
Method: Standard Methods 12th Ed. 1965. Henriksen, A: Automatic Modification.
Instrument: Technicon Autoanalyzer I.
NB: Water samples converved with HgCl₂.

1965-01 – 1970-12
Method: Karlgren, L. 1961, Vattenkemiska analysmetoder (Hydrochemical Analytical Methods, in Swedish). Fotometrisk bestämning av molbyldatreaktivt kisel (Photometric determination of molbyldate-reactive silicon, in Swedish).
NB: Water samples converved with HgCl₂.