This research aims to determine the effectiveness of the use of pins chip mixture of acacia and eucalyptus wood and the optimum condition of the quality of the pulp.

This research aims to determine the effectiveness of the use of pins chip mixture of acacia and eucalyptus wood and the optimum condition of the quality of the pulp. The cooking conditions for kraft pulp were alkalinity (17%, 18%, and 19%) and sulfidity were the same in each test (31.28%). Maximum cooking temperature is 160°C for 3 hours, with H-Factor 800. Bleaching of pulp pins chips using three processes, namely D0, EOP, and D1. Pulp properties test consists of physical strength and optical test. The ripening conditions for kraft pulp resulted in a fairly high pulp yield of about 50.93% at 17% active alkaline charge condition, 51.07% at 18% active alkaline charge condition, and 51.42% at 19% active alkaline charge condition. The use of acacia and eucalyptus pins chips was effective enough to produce a fairly high yield with a range of 40-55%, with the lowest kappa number 1.12 and the highest 1.23. The effect of increasing the concentration of alkali is more effective at 19% active alkaline charge conditions, but the resulting viscosity is very low, as well as 17% active alkaline charge conditions are less effective but the viscosity is quite high. The ideal conditions of active alkaline charge are 18% with 50.93% pins chip yield, 720 cm3/g viscosity, and 89.03% ISO brightness. In general, different concentrations of active alkali charge white liquor affect the physical strength and optical properties.