摘要 |
The process is based on the separated recycling of two parts of an anion exchanger in the original chloride form. The first part is partially recycled by a solution containing sulphur ions, preferably in a concentration less than 0.5 mol/l. The second part is partially recycled by a solution containing hydrogen carbonate ions, preferably in a concentration less than 0.5 mol/l. Both parts are mixed together in such a ratio that the resulting representation of the functional groups in the mixture is 50 to 98 % sulphuric forms, 2 to 50 % chloride forms and 2 to 50 % hydrogen carbonate forms. |