Comparative studies of retted jute fiber, jute cuttings and jute caddis were carried out in producing dissolving and paper grade pulp. Fiber length of jute fiber was longer than jute cutting and caddis. Klason lignin content was lower and a-cellulose content higher in jute fiber than cuttings and caddis. Extractives content in caddis was higher than jute fiber and cuttings. Pulping of these raw materials was done in sodaanthraquinone process. Higher pulp yield and lower kappa number was observed in jute fiber than that of jute cuttings and caddis. Jute fiber pulp showed better papermaking properties than jute cuttings and caddis. The tear index of these raw materials was similar to softwood. The bleachability of jute fiber pulp was also better than that of cuttings and caddis. These three raw materials were also evaluated in producing dissolving pulp by prehydrolysed kraft process. Pulp yield and bleachability was higher and kappa number lower for jute fiber than jute cuttings and caddis, but α-cellulose, S 10 and S 18 values and viscosity were almost similar in these three raw materials.

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Dissolving pulps are the raw materials of cellulose derivatives and of many other cellulosic products. Jute is a very good source of cellulose and worthy of consideration for the production of dissolving pulp. In this investigation jute fiber, jute cuttings, and jute caddis were used as raw materials to prepare dissolving pulp by a formic acid process. A very high bleached pulp yield (49 to 59%) was obtained in this process. The alpha-cellulose content was 93 to 98%, with a high pulp viscosity. Also a good brightness (81 to 87%) was achieved in totally chlorine free bleaching. Jute fiber showed the best and jute caddis showed lowest performance in producing dissolving pulp via the formic acid process. R18-R10 values were much lower than for conventional dissolving pulp.

In this paper, physical, morphological and chemical characterizations of the six main mangrove species of Bangladesh [namely Keora (Sonneratia apetala), Gewa (Excoecaria agallocha), Bine (Avicennia alba), Sundari (Heritiera fomes) Pashur (Xylocarpous mekongests) and Kakra (Bruguiera gymnorhiza)] were discussed in order to assess the suitability of pulping raw materials. The wood density of these six mangrove was found to be 0.5-0.6 g cm -3 except Gewa which had 0.39 g cm -3 . The fiber length of these species was varied from 0.74 to 1.2 mm that was considered as short fiber. Sundari contributed the longest fibre length (1.2 mm) among these six species. The chemical results revealed that these species contain high percentages of dichloromethane, followed by methanol extractives. Methanol extracts in Pashur, Sundari and Bine was higher than 10 %, which indicates high percentage of tannin material. These species were characterized with high lignin content and low a-cellulose content. The pulping of these six mangrove species was also carried out by kraft process and papermaking properties were also evaluated. Pulp yield was lower and kappa number was higher as compared with other tropical hardwoods. But the physical properties of these species were quite acceptable. Considering pulp yield, kappa number and physical properties, it may be concluded that Keora and Gewa can be used as kraft liner and other packaging grade paper pulp.

Dhaincha (Sesbania aculeata) is one of the annual plants in Bangladesh that has potential as a fiber source. It is a crop generally cultivated for its nutritive value to soil. This paper describes the effect of harvesting age of dhaincha on chemical, morphological, pulp, and papermaking properties and its bleachability. Dhaincha is a short length fiber that can be used as a substitute to hardwood. Fiber length was found to increase slightly with increasing age of the plant. The alpha-cellulose content in dhaincha increased and pentosan decreased with increasing age. Dhaincha pulp was prepared from 2, 3, 4, 5, and 6 month old plants under identical cooking conditions. Pulp yield (43-45 %) and kappa number (26-30) did not follow direct correlation with plant age. But physical properties of unbleached pulp increased linearly with the increase of age. Bleachability of dhaincha pulp was quite poor. The bleachability of pulp was improved when the age of dhaincha was increased.