| abstract |
The invention is an improvement in a process for making cellulosic articles said process involving a separation of cellulosic material from a mixture containing a liquid, metal cations, and cellulosic material. The improvement involves adding to the mixture at least one retaining material which binds at least one metal cation and, in the separation, is retained with the cellulosic material. Suitable retaining agents are either organic or inorganic and include chelate-forming polymers, both synthetic and natural, colloidal suspensions of inorganic compounds, and mixed metal hydroxides. In each case, the metal cations remain in the cellulosic article, for example paper, rather going into waste water from which they would otherwise need to be removed. |