TN44: The Determination of Trace Anions in Concentrated Phosphoric Acid

Instrument Type: IC

The determination of trace anions in phosphoric acid is hampered by a large excess of phosphate ion. Diluting the concentrated sample overcomes the problem of a large concentration of the interfering matrix ion, but lacks the required sensitivity for the contaminant ions of interest. An improved method for determining trace anions in concentrated phosphoric acid has been developed to overcome this problem. This Technical Note describes the theory, set up, and analytical procedure for the determination of chloride, nitrate, and sulfate at sub-mg/L (ppm) levels in 85% (w/w) phosphoric acid.

AN94: Determination of Trace Cations in Concentrated Acids (Phosphoric Acid) Using AutoNeutralization Pretreatment and Ion Chromatography

Instrument Type: IC

The determination of trace cationic contamination in processing acids (phosphoric, sulfuric, hydrofluoric) is important to the electronics industries to minimize corrosion. Here trace cationic contamination is determined in a 25% phosphoric acid sample. The acid sample is automatically neutralized through an electrolytic device, and then retained and concentrated onto a concentrator column. After eluting from the concentrator column, the µg/L cations are determined on an IonPac CS16 column using electrolytically generated MSA eluent and suppressed conductivity detection.

AN169: Rapid Determination of Phosphate and Citrate in Carbonated Soft Drinks Using a Reagent-Free Ion Chromatography System

Instrument Type: IC

This application presents a method using a RFIC system for the simultaneous determination of phosphate and citrate in carbonated soft drinks using the hydroxide-selective Dionex IonPac Fast Anion III column.