Patent ID: 8419897
Filing Date: 2013-04-16
Classification: C11B,Y02W

Abstract:
1. A method for producing crude tall oil from black liquor soap while removing calcium and lignates, comprising: (a) combining a black liquor soap comprising tall oil soap, lignates. and inorganic solids comprising calcium carbonate, with an alkaline wash medium, wherein the alkaline wash medium has a pH from 10 to 14 and a lower concentration of lignates and inorganic solids than the black liquor soap, at a temperature within the range of 25° C. to 100° C. to produce a mixture comprising washed tall oil soap, fortified brine, lignates, and calcium carbonate; wherein the alkaline wash medium has a lignate content <1.0 wt. % and a filterable inorganic solids content <200 ppm: (b) separating the mixture by centrifugation, decantation, filtration, settling, or a combination of these techniques to provide, in addition to the washed tall oil soap: (c) acidifying the washed tall oil soap isolated in step (b) to give crude tall oil and a spent acid mixture; and (d) isolating the crude tall oil.