Influence of pitch composition and wood substances on the phase distribution of resin and fatty acids at different pH levels

Pitch emulsions were prepared to mimic the colloidal wood resin system in paper mill process waters. The phase distribution of resin and fatty acids (RFAs) between the colloidal lipophilic droplets (l) and the water phase (w) were determined as pKlw values. The effect of triglyceride to RFA ratio on pKlw values was studied, to determine if seasonal variations in wood extractives influence their phase distribution. The effect of water-soluble hemicelluloses on pKlw values was also determined. The pKlw values of the RFAs were lower in emulsions with a low triglyceride to RFA ratio. Addition of water-soluble galactoglucomannans also lowered the pKlw values of the RFAs.