| 摘要 |
This method will produce depolymerized lignins substantially free from sodium compounds. Black liquor supplied from a pulping process is utilized for providing a mixture of depolymerized lignins dispersed and dissolved in absolution containing sodium hydroxide. The mixture is then separated to form depolymerized lignins and a solution containing sodium hydroxide. Following separation, the depolymerized lignins are then extracted with water to produce an extractate containing water soluble sodium compounds. The extracted depolymerized lignins, containing sodium compounds, are then reacted with an acid to form sodium salts. The solution containing sodium salts is then separated from the extracted depolymerized lignins to produce substantially sodium free depolymerized lignins. The separated solution containing sodium hydroxide is combined with the extractate and the combination, subsequent to removal of water, is made available to reuse for recycle to depolymerize, disperse and dissolve additional lignins. As a result a mixture containing depolymerized lignins is created.
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