The proposed mechanism was verified using data from experiments with model solutions. This was attributed to size-exclusion of individual ions which leads to co-operative sorption of NaOH in the presence of the sodium salts of hydroxy acids. As an example, an SEC HPLC method for the separation of a mAb using 5 m, 7.8 mm ID × 30 cm SEC column (TSKgel G3000SWXL) was transferred to a 2 m, 4.6 mm ID × 30 cm SEC column (TSKgel UP-SW3000 SEC) on a UHPLC instrument. High column loadings, up to 25% of the bed volume, were found applicable for separation of authentic solutions without compromising the resolution. Fouling did not reduce the separation capability of the separation medium in extended runs with more than 40 consecutive injections. Hydroxy acids were successfully separated from sodium hydroxide and the lignin content of the product fraction was reduced significantly. Ultrafiltered black liquors from soda cooking of hardwood and softwood were used as feed and Sephadex G-10 as the stationary phase. In this work, chromatographic recovery of hydroxy acids and cooking alkali (NaOH) from spent pulping liquor using size-exclusion chromatography (SEC) is investigated.
0 Comments
Leave a Reply. |