Avoiding Matrix Interferences in Ion Chromatography Using Solid

Avoiding Matrix Interferences in Ion Chromatography Using Solid Phase Extraction Alltech Associates, Inc. Brandstraat 12, 9160 Lokeren Phone: 09 340 65 65 • Web Site: www. alltechweb. com a Grace company

Types of Sample Matrix Interferences in Ion Chromatography • Samples with components that will damage the column. • Samples that are too acidic for cation analysis. • Samples that are too basic for anion analysis. • Samples that contain high concentrations of interfering ions. a Grace company

Problems with Common Sample Preparation Techniques Dilution and Filtration are not suitable when: • The analytes are present at trace levels. • The analytes differ greatly in concentration. • soluble. Interfering compounds and analytes are both a Grace company

Solid Phase Extraction (SPE) Cartridges for Ion Chromatography • Stable from p. H 2 to 13. • Low IC interference levels. • Requires only 2 - 3 m. L of samples. a Grace company

The Alltech Maxi-Clean™ IC Cartridge Construction Polypropylene Housing Packing Material Female Luer Inlet Male Luer Outlet Polyethylene Frits a Grace company

Types of Maxi-Clean™ IC SPE Cartridges: • Maxi-Clean™ IC-RP • Maxi-Clean™ IC-Ag • Maxi-Clean™ IC-Ba • Maxi-Clean™ IC-OH • Maxi-Clean™ IC-Na • Maxi-Clean™ IC-Chelate a Grace company

General Procedure for Using Maxi-Clean™ IC Cartridges 1. Precondition the cartridge by passing 5 -10 m. L of IC grade water (use 5 m. L of methanol followed by 5 m. L of Water for Maxi-Clean™ IC-RP). 2. Load the sample at a rate of 1 m. L/min or less. (Adjust the sample size to use 50% or less of the device’s capacity). 3. Discard the first 1 m. L eluate. 4. Collect and analyze the remaining eluate. a Grace company

Maxi-Clean™ IC-RP Product Specifications Packing: Polystyrene Particle Size: 300µm Retains: Hydrophobic components by a reversed-phase mechanism Applications: Removal of hydrophobic organic components a Grace company

Maxi-Clean™ IC-RP Removes Organic Contaminants 5351 Trace Anions in Aniline 1. Chloride 2. Nitrate 3. Sulfate Column: Mobile Phase: Flowrate: Detector: Original Sample a Grace company After Cleanup with Maxi-Clean™ IC-RP Anion/S, 250 x 4. 1 mm 4 m. M KHP p. H 4. 5 2. 0 m. L/min Alltech Conductivity

Average % Recovery of Ions with Maxi-Clean™ IC-RP Cartridge a Grace company

Sample Preparation by Precipitation Maxi-Clean. TM IC-Ba • to analysis For removal of sulfate and phosphate prior Resin-2 -Ba+2 + M+2 SO 4 -2 Ba+2 SO 4 -2 Resin-2 -M+2 + Maxi-Clean. TM IC-Ag • For removal of halides prior to analysis Resin--Ag+ + M+X- M=Sample cations X= Cl-, Br-, I- a Grace company Resin--M+ + Ag+X-

The Solubility of Barium and Silver Salts in Aqueous Solutions Compound Solubility (g/100 m. L) Temperature (°C) 0. 12 37. 5 67. 5 8. 7 0. 01 - 0. 02 2. 2 x 10 -4 182 2. 8 x 10 -7 8. 9 x 10 -5 0. 155 3. 7 x 10 -4 122 0. 57 25 26 20 20 N/A 25 15. 5 25 10 0 100 Ba. F 2 Ba. Cl 2 Ba(NO 2)2 Ba(NO 3)2 Ba. HPO 4 Ba 2 SO 4 Ag. F Ag. I Ag. Cl Ag. NO 2 Ag. Br Ag. NO 3 Ag 2 SO 4 a Grace company

Maxi-Clean™ IC-Ba Product Specifications Packing: Particle Size: Capacity: Retains: Applications: Strong cation exchanger in the Ba 2+ form 106µm 0. 8/2. 4 meq. Sulfate by precipitation Removal of sulfate before the analysis of other anions a Grace company

Maxi-Clean™ IC-Ba Removes Sulfate 5348 Anions in Battery Acid 1. 2. 3. 4. 5. 6. 7. Fluoride Chloride Nitrite Bromide Nitrate Phosphate Sulfate Column: Mobile Phase: Flow rate: Detector: Original Sample a Grace company After Cleanup with Maxi-Clean™ IC-BA Anion/R, 250 x 4. 1 mm 5 m. M p HBA, p. H 8. 5 1. 5 m. L/min. Alltech Conductivity

Average % Recovery of Ions with Maxi-Clean™ IC-Ba Cartridge a Grace company

Maxi-Clean™ IC-Ag Product Specifications Packing: Particle Size: Capacity: Strong cation exchanger in Ag+ form Retains: Halides by precipitation Removal of halides before analysis of other anions Applications: 106µm 0. 8/2. 4 meq. a Grace company

Maxi-Clean™ IC-Ag Removes Chloride 5347 1 Nitrite in Brine 1. Chloride 2. Nitrite 2 Original Sample a Grace company After Cleanup with Maxi-Clean™ Column: 250 x 4. 1 mm Packing: Anion/R Mobile Phase: 5 m. M p HBA, p. H 8. 5 Flow rate: 1. 5 m. L/min. Detector: Alltech Conductivity

Average % Recovery of Ions with Maxi-Clean™ IC-Ag Cartridge a Grace company

Maxi-Clean™ Cartridges to Adjust Sample p. H • Baseline disturbances and/or system peaks result when sample p. H differs from eluant p. H. • Strong anion exchange resin in the hydroxide form removes anions and neutralizes an acidic sample. • Cation exchange resin in the hydrogen form removes cations and neutralizes an alkaline sample. a Grace company

Maxi-Clean™ IC-OH Product Specifications Packing: Particle Size: Capacity: Retains: Applications: a Grace company Strong anion exchanger in OH- form 75µm 0. 6/1. 8 meq Anions Adjusting sample p. H before cation analysis

Maxi-Clean™ IC-OH Neutralizes Acid 5352 Monovalent Cations in 1 M Nitric Acid 1. Sodium 2. Potassium Column: Cation/R, 100 x 43. 1 mm Mobile Phase: 3. 2 m. M nitric acid Flowrate: 1. 0 m. L/min Detector: Alltech Conductivity Original Sample a Grace company After p. H Neutralization with Maxi-Clean™ IC-OH

Recovery of Ions with Maxi-Clean™ IC-OH Cartridges a Grace company

Maxi-Clean™ IC-H Product Specifications Packing: Particle Size: Capacity: Retains: Applications: a Grace company Strong cation exchanger in H+ form 106µm 0. 8/2. 4 meq. Cations Adjusting sample p. H before anion analysis

Maxi-Clean™ IC-H Neutralizes Hydroxide Trace Anions In Caustic Solution 1. 2. 3. 4. 5. 6. 7. 8. Original Sample After p. H Neutralization with Maxi-Clean™ IC-H a Grace company 5349 Fluoride Bicarbonate Chloride Nitrite Bromide Nitrate Phosphate Sulfate Column: Anion/R, 150 x 4. 1 mm Mobile Phase: 5 m. M p. HBA, p. H 8. 5 Flowrate: 1. 5 m. L/min. Detector: Alltech Conductivity

Recovery of Ions with Maxi-Clean™ IC-H Cartridges a Grace company

Maxi-Clean™ IC-Na Product Specifications Packing: Particle Size: Capacity: Retains: Applications: Strong cation exchanger in Na+ form 106µm 0. 8/2. 4 meq. Cations (exchanges cations for sodium) Removal of cations from sample without changing sample p. H a Grace company

Maxi-Clean™ IC-Na+ Isolates Iron (III) 5813 Analysis of Iron (III) Procedures: 1. Precondition IC-Na+ cartridge with 5 m. L water. 2. Load the sample to preconcentrate iron (III) present. 3. Wash with 10 m. L water. 4. Elute the iron (III) with 5 m. L of 25 m. M EDTA, disodium salt. 5. Analyze the eluant for iron (III). 1. Iron (III) Column: Alltech Universal Anion, 150 x 4. 6 mm Mobile Phase: 2 m. M EDTA, disodium salt Flowrate: 1. 0 m. L/min. Detector: UV at 330 nm *Problem with IC-H+--> the precipitation of H 4 EDTA a Grace company

Maxi-Clean™ IC-Chelate Product Specifications Packing: Particle Size: Capacity: Retains: Applications: a Grace company Styrene-divinylbenzene copolymer containing iminodiacetate ion 225µm 0. 2/0. 6 meq. Polyvalent metal ions (exchanges cations for sodium) Removal of polyvalent metal ions from sample

Benefits of Alltech Maxi-Clean™ IC Cartridges • Remove interfering components from the sample matrix. • Little or no loss of sample. • Easy, quick, and convenient. • Disposable. a Grace company