CarbEx II CarbEx is a styrene-divinylbenzene copolymer filler. The cation exchanger filler material is available with the following counterions: H and Ca form. The filling material has a very good chemical and physical stability. It can be used up to 120 bar pressure and a temperature of 90 ° C. The eluent may contain up to 70% methanol. The eluent should be well filtered and degassed. The sample should also be filtered before injection. Use in-line filters to protect the column, and possibly a short guard column (e.g., 30 mm in length). Do not load the column immediately with the full flow velocity and thus a high pressure. Slowly increase the flow rate from 0.1 ml / min to its working flow rate (e.g., 0.5-0.8 ml / min for a 250 x 8.0 mm column). The column should be tempered while operating. This gives you a faster analysis with better peak shapes and narrower peaks, as well as lower pressure. 40-65 ° C is the ideal working temperature range. Above 50 ° C, you will not get any significant separation effects. Please note that very clean, double-distilled water must be used for Ca-shaped columns.