Chemical and morphological characterization and pulping of Casuarina equisetifolia
Abstract Bangladesh is very much successful in coastal afforestation programmes, which protects from frequent cyclones. Casuarina equisetifolia has showed a climate resilient and promising species. No study has been done on industrial application of C. equisetifolia in Bangladesh. In this study, C. equisetifolia was characterized in terms of chemical, morphological and anatomical properties. It is characterized with higher α-cellulose, similar hemicelluloses and lignin as compared to other hardwood species grown in Bangladesh. The C. equisetifolia lignin contained mainly of syringyl unit followed by guaiacyl unit. The fiber of C. equisetifolia was shorter in length with very thick cell wall and narrow lumen, consequently the wood density and runkel ratio were very high (2.89). The C. equisetifolia was also fractionated by formic acid (FA) at atmospheric pressure to pulp, dissolved lignin and hemicelluloses. Pulp yield was 50 % with kappa number of 40 at the conditions of 3 h treatment with 90 % FA followed by 2 h peroxyformic acid treatment. But in the kraft process, C. equisetifolia produced pulp yield of 44 % with kappa number 17. Both pulps showed good bleachability. The papermaking properties were in acceptable range. Finally, it can be said that C. equisetifolia is promising species for pulping.