Using the Pitzer method to estimate the boiling point rise in black liquor solutions
Artikel i vetenskaplig tidskrift, 2009

The b.p. rise (elevation) of aq. industrial solns. is often of significant importance for the design of process conditions, equipment, heat balances, etc. However, few rigorous methods exist for predicting b.p. elevation in complex, multicomponent, electrolyte solns. An example of such a soln. is the black liquor obtained in kraft pulp prodn.: a complex mixt. of org. and inorg. ions including Na+, K+, OH-, HS-, CO32-, SO42-, S2O32-, CH3COO-, various phenolates and many more. This work shows one application of the semi-empirical Pitzer method to the theor. prediction of the b.p. rise in industrial black liquor solns. The values of the b.p. elevation were measured in two series of black liquors from representative Swedish mills, including both the original and lignin-lean black liquor at different solid contents. The results show a good agreement between exptl. and predicted values at low to moderate solid content, and good qual. prediction at high solid content.

Boiling point rise (elevation)

Pitzer model/method

Electrolyte

Activity

Black liquor

Osmotic coefficient

Författare

Marta Anna Bialik

Chalmers, Kemi- och bioteknik, Skogsindustriell kemiteknik

Ali Seid Moosavifar

Chalmers, Kemi- och bioteknik, Skogsindustriell kemiteknik

Maria Sedin

Chalmers, Kemi- och bioteknik, Skogsindustriell kemiteknik

Hans Theliander

Chalmers, Kemi- och bioteknik, Skogsindustriell kemiteknik

Nordic Pulp and Paper Research Journal

0283-2631 (ISSN)

Vol. 24 2 172-182

Ämneskategorier

Fysikalisk kemi

Pappers-, massa- och fiberteknik