Pulping of retted jute fiber (Corchorus capsuiaris) by soda-additive processes

Pulping of jute was performed by soda-hexamethylene tetramine (HMTA) or sodanitrobenzene (NB) liquor. The factors influencing the pulping processes were: cooking time (1-4 hours), and HMTA (0.05%-0.5%) or NB (1-10%) concentration on o.d. raw material. Temperature, material-to-liquor ratio and alkali concentration were kept constant at 170°, 1:6 and 18% as NaOH, respectively. The rate of delignification by soda-HMTA or soda-NB liquor was exceeded only for the soda liquor. Pulp yield was also increased by the addition of HMTA or NB in the soda liquor. The chemical constituents of soda-HMTA and soda-NB pulps were better than those of the soda pulp. After 0.1% HMTA, the above-mentioned quality was not significantly improved and, after 2%NB, the reverse effect on pulping was observed. Tensile, burst and tear strength were improved in soda-NB and soda-HMTA pulping. The double fold number of soda-HMTA pulp deteriorates remarkably, increasing nevertheless in soda-NB pulp.