US 11,970,816 B2
Dual surfactant digester additive composition and a method for enhancing the pulping of wood chips using the same
Michael M. Blackstone, Jacksonville, FL (US); and Peter Spizzirri, Greenville, SC (US)
Assigned to ChemStone, Inc., Greenville, SC (US)
Filed by ChemStone, Inc., Greenville, SC (US)
Filed on Aug. 11, 2021, as Appl. No. 17/399,099.
Application 17/399,099 is a division of application No. 15/827,137, filed on Nov. 30, 2017, granted, now 11,091,875.
Claims priority of provisional application 62/428,072, filed on Nov. 30, 2016.
Prior Publication US 2021/0372048 A1, Dec. 2, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. D21C 3/06 (2006.01); C07C 309/86 (2006.01); C08L 71/08 (2006.01); D21C 3/20 (2006.01); D21C 3/22 (2006.01); D21C 7/10 (2006.01); D21H 21/24 (2006.01)
CPC D21C 3/222 (2013.01) [C07C 309/86 (2013.01); C08L 71/08 (2013.01); D21C 3/06 (2013.01); D21C 3/20 (2013.01); D21C 7/10 (2013.01); D21H 21/24 (2013.01)] 19 Claims
 
1. A digester additive composition comprising,
a first surfactant comprising an anionic surfactant, a derivative thereof, a salt thereof, or any combination thereof, and
a second surfactant comprising an ester derivative of a polyoxyalkylene glycol wherein the ester derivative is obtained from an acid having from 12 to 25 carbon atoms.