Influence of pulping variables on the properties of Elaeis guineensis soda pulp as evaluated by response surface methodology

Response surface methodology with central composite design was used to investigate the influence of pulping conditions, viz. cooking temperature, time-at-temperature and alkali charge for alkaline pulping of oil palm empty fruit bunch fibres, on the properties of the pulp and paper obtained (screened yield, Kappa number, tensile and tear indices). Quadratic models consisting of the three independent variables were found to accurately describe the pulping of this material with correlation between the actual and predicted values of the response variables having a relatively good degree of R². The delignification of oil palm empty fruit bunch fibre can be achieved with ease using sodium hydroxide as the sole cooking agent to about 30–45% yield with the process greatly enhanced by an increase in temperature. Although, a relatively low temperature (about 160°C) within the limits of pulping time (60–120 min) and of alkali charge between 20 and 30% is generally sufficient.