Steam Explosion Pulping of Kenaf: A Preliminary Study on Pulp Characteristics and a Comparison with Simulated CMP and CTMP of Kenaf

The use of kenaf as a raw material for the preparation of ultra-high-yield pulp by applying conventional (CMP and CTMP) and non-conventional (explosion pulping) process conditions, has been investigated. Explosion pulping conditions used for kenaf pulping are actually the optimum conditions for aspen pulping. The effects of impregnation chemicals on explosion pulp properties are examined while the cooking time and temperature are kept constant at optimum level. Breaking length of kenaf explosion pulp is undoubtedly higher than that of simulated CMP and CTMP, even in the case of lower ionic content-Tear values of explosion pulp, CMP and CTMP are similar when the impregnation chemicals contain 1% NaOH in addition to 8% Na2S03. The relative specific refining energy requirements of explosion pulp, CMP and CTMP are greatly influenced by impregnation chemicals. Sulfonate content of explosion pulp depends on the chemical charge. Pulp yield, brightness and opacity decrease with the rise of the sulfonate content of pulp achieved by increasing the chemical charge or by adding NaOH along with Na2SO3. The kenaf explosion pulp can be bleached to 77% from an initial 57% level by using 3 to 4% H202 in a peroxide bleaching process.