1. Scope

1.1 This test method covers the determination of anionic impurities in 50% caustic soda (sodium hydroxide) and 50% caustic potash (potassium hydroxide) solutions using ion chromatography (IC). Anions that can be determined at concentrations of approximately 0.1-1000 ppm include: bromide, chlorate, chloride, fluoride, nitrate, phosphate, and sulfate.

1.2 By varying the sample size, this test method can be used for anhydrous caustic soda and caustic potash products, as well as other concentrations of liquid products.

1.3 This test method is not intended to be used to quantify chloride in caustic soda where the sodium chloride concentration is approximately 1%. For the most accurate determinations, it is recommended that high concentrations of chloride be analyzed using a potentiometric titration procedure, such as the one described in Test Methods E291.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazards statements are given in Section 8.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

D1193 Specification for Reagent Water

E180 Practice for Determining the Precision of ASTM Methods for Analysis and Testing of Industrial and Specialty Chemicals

E291 Test Methods for Chemical Analysis of Caustic Soda and Caustic Potash (Sodium Hydroxide and Potassium Hydroxide)

Keywords

bromide; caustic potash; caustic soda; chlorate; chloride; chromatography; fluoride; ion chromatography; nitrate; phosphate; potassium hydroxide; sodium hydroxide; sulfate; Anionic impurities; Bromide; Caustic potash; Caustic soda; Chlorate; Chloride analysis--cleaning agents/detergents; Fluoride compounds; Ion chromatography (IC); Nitrate (ion) analysis; Phosphate (ion) analysis; Potassium hydroxide; Sodium hydroxide; Sulfate (ion) analysis;

ICS Code

ICS Number Code 71.040.50 (Physicochemical methods of analysis); 71.060.40 (Bases)

DOI: 10.1520/E1787-96

ASTM International is a member of CrossRef.