BS EN ISO 10304-3:1997

This standard BS EN ISO 10304-3:1997 Water quality. Determination of dissolved anions by liquid chromatography of ions is classified in these ICS categories:

• 13.060.50 Examination of water for chemical substances

This part of ISO 10304 specifies methods for the determination in aqueous solution of the dissolved anions

• iodide, thiocyanate and thiosulfate (clause 4);

• sulfite (clause 5);

• chromate (clause 6).

An appropriate pretreatment of the sample (e.g. dilution) and the application of a conductivity detector (CD), UV detector (UV) or amperometric detector (AD) make the working ranges given in table 1 feasible.

Table 1

Applicable working ranges

Anion	Working range1)	Detector
Chromate (CrO4), clause 6	0,05 mg/l to 50 mg/l	UV (λ = 365 nm)
Iodide (I), clause 4	0,1 mg/l to 50 mg/l	CD or UV (λ = 205 nm to 236 nm) AD (approximately 0,7 V to 1,1 V)
Sulfite (SO3), clause 5	0,1 mg/l to 50 mg/l 0,5 mg/l to 50 mg/l	CD UV (λ = 205 nm to 220 nm)
Thiocyanate (SCN), clause 4	0,1 mg/l to 50 mg/l	CD or UV (λ = 205 nm to 220 nm) AD (approximately 0,7 V to 1,1 V)
Thiosuifate (S2O3), clause 4	0,1 mg/l to 50 mg/l	CD or UV (λ = 205 nm to 220 nm) AD (approximately 0,7 V to 1,1 V)

¹⁾ The working range is restricted by the exchange capacity of the columns. Dilute the sample into the working range if necessary.