Auto-regeneration of anion-trap columns for improved determination of silica by ion chromatography

The goal of this project was to develop an automated method to regenerate the ATC-3 trap columns that are used on the DX-800 on-line ion chromatography silica systems. The old method of regenerating the ATC-3 trap columns was to physically remove the trap columns from the silica system once every 2 weeks and manual regenerate them. A new automated regeneration method was developed by re-plumbing the silica system to allow 300 mM NaOH to run as the eluent. This regenerates the trap column automatically once every 24 h. The data have shown that regenerating the ATC-3 trap columns once per day improves the R.S.D. values for 250 ng/l silica analysis from 26.0 to 8.7%. The length of useful lifetime for the silica concentrator column was increased by an average of 9 months.