Paper pulp prepn. from dicotyledonous plants - gives high yields of bast fibres using an oxidising agent during pulping (BR 18.10.77)

摘要

The plants are stirred in a pulper in an alkaline soln. in the presence of a surfactant and >=1 stain inhibiting agent. This agent is a peroxide or sodium hypochlorite, and prevents staining of the plant fibres. The resultant stock contains a woody core fraction and a bark fraction of bast fibres, and these fractions are divided by a suitable method. The bark fraction is subsequently cooked and bleached under atmospheric pressure in an alkaline soln. contg. an alkyl sulphate surfactant and either H2O2 or tert. butyl hydroperoxide. The method produces bast fibres in higher yield, but still retaining good brightness characteristics, cf. other techniques.