Development of methodology for extracting tall oil from the effluent black liquor generated in the production of cellulose

Abstract

The "black liquor" effluent generated in the production of paper and cellulose is highly polluting, toxic and has high levels of fatty and resinous acids. In view of this scenario, the objective of this work was to develop the most efficient methodology for extracting tall oil from the "black liquor" effluent generated in paper and pulp production. Effluent and tall oil foam were collected at a pulp and paper production company in the city of Fraiburgo, Santa Catarina. Initially the effluent characterization and pretreatment with refining in the tall oil foam were done. The crude effluent showed total organic matter (54.2 %), total solids (39.2 %), oils and total greases (3.4 %), viscosity (760.5 cP) and alkali pH. The characterization of the refined oil was performed by flash point, viscosity, infrared spectroscopy, gas chromatography coupled with mass spectrometry (CG-MS). 54.26 % of oil was obtained and the infrared showed the absorption in the region of 1715 cm-1, characteristic of carboxylic acids. The results of the analysis by CG-MS, showed an oil rich in unsaturated and polyunsaturated fatty acids.