US 12,391,807 B2
Extraction of valuable components from bark
Tarja Tamminen, Espoo (FI); Klaus Niemelä, Espoo (FI); Stina Grönqvist, Espoo (FI); Sami Alakurtti, Espoo (FI); Miikka Ruuskanen, Espoo (FI); and Anna Kalliola, Espoo (FI)
Assigned to Teknologian tutkimuskeskus VTT Oy, Espoo (FI)
Appl. No. 17/287,145
Filed by Teknologian tutkimuskeskus VTT Oy, Espoo (FI)
PCT Filed Oct. 23, 2019, PCT No. PCT/FI2019/050756
§ 371(c)(1), (2) Date Apr. 21, 2021,
PCT Pub. No. WO2020/084196, PCT Pub. Date Apr. 30, 2020.
Claims priority of application No. 20185891 (FI), filed on Oct. 23, 2018.
Prior Publication US 2021/0395466 A1, Dec. 23, 2021
Int. Cl. C08H 7/00 (2011.01); D21C 1/02 (2006.01); D21C 1/04 (2006.01); D21C 3/02 (2006.01); D21C 11/00 (2006.01)
CPC C08H 6/00 (2013.01) [D21C 1/02 (2013.01); D21C 1/04 (2013.01); D21C 3/02 (2013.01); D21C 11/0007 (2013.01)] 19 Claims
OG exemplary drawing
 
19. A process for extraction of valuable components from a tannin-rich bark raw-material, the process comprising:
carrying out a pre-treatment on the bark raw material, before an alkaline cooking step, to remove, or at least to decrease the content of silicon and ashes, the pre-treatment comprising washing the bark material with one or more acids or chelating agents at a temperature of 30-50° C., and separating and collecting solids for the alkaline cooking step, and
carrying out the alkaline cooking step of the tannin-rich bark raw-material, followed by acid precipitation to provide a solid fraction comprising the valuable components, wherein the alkaline cooking step comprises using a white liquor comprising sodium hydroxide (NaOH), thereby obtaining a black liquor comprising polyphenols.