Soda-AQ pulping of wheat straw

Delignification of wheat straw was carried out by conventional soda-AQ pulp ing under varying conditions to determine the relationships between selecte d cooking variables (EA, 12 to 18%; maximum temperature, 145 to 165 degrees C; time to maximum temperature, 70 to 110 min; and time at maximum temperat ure, 0 to 30 min) and pulp properties (yield, Kappa number, and viscosity). EA, maximum temperature, and time at maximum temperature affected pulp yie ld and Kappa number with almost equal intensity, whereas maximum temperatur e and time at maximum temperature both had a significant effect on pulp vis cosity. Contrary to wood-based pulping, the viscosity of wheat straw pulp i ncreased as the Kappa number fell.