Title
Response surface modeling of wheat straw pulping using sodium carbonate and sodium hydroxide mixtures
Authors
NARCISA MARIN ADRIAN CATALIN PUITEL ANA-MARIA CHESCA and DAN GAVRILESCU

Received September 16, 2016
Published Volume 51 Issue 7-8 July-August
Keywords straw, pulping, yield, paper strength

Abstract
The paper presents the results of experimental trials regarding pulping of wheat straw by using mixtures of sodium carbonate and sodium hydroxide as pulping reagents. Although sodium carbonate has been proved as a potential pulping reagent for obtaining higher yield pulps from wheat straw, the presence of sodium hydroxide improves delignification. Response surface methodology with Central Composite Design has been used as a method for the study of process parameters: temperature, alkali charge and Na2CO3/NaOH mass ratio were chosen as independent variables. The studied pulp characteristics were the following: yield, kappa number, tensile index, burst index, corrugating medium flat crush resistance and short span compression resistance. The influence of each variable on pulp characteristics, as well as their interactions, has been established. The results of the study and the obtained quadratic equations model equations may provide the basis for selecting the optimal conditions of pulping according to the desired pulp characteristics.