	US 12,234,604 B2
	Modified sulfuric acid and uses thereof
Clay Purdy, Medicine Hat (CA); Markus Weissenberger, Calgary (CA); Markus Pagels, Calgary (CA); and Kyle G Wynnyk, Calgary (CA)
Assigned to SIXRING INC., Calgary (CA)
Filed by SixRing Inc., Calgary (CA)
Filed on Mar. 18, 2024, as Appl. No. 18/608,493.
Application 18/608,493 is a division of application No. 17/407,515, filed on Aug. 20, 2021, granted, now 11,965,289.
Claims priority of application No. CA 3110389 (CA), filed on Feb. 25, 2021.
Prior Publication US 2024/0229354 A1, Jul. 11, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. D21C 3/00 (2006.01); D21C 3/04 (2006.01); D21C 3/22 (2006.01)

CPC D21C 3/003 (2013.01) [D21C 3/04 (2013.01); D21C 3/22 (2013.01)]

15 Claims

1. A one-pot process to separate lignin from a lignocellulosic feedstock, said process comprising the steps of:

providing a vessel;

providing the lignocellulosic feedstock;

providing a composition comprising;

sulfuric acid;

a modifying agent comprising a heterocyclic compound and an alkylsulfonic acid; and

a peroxide;

exposing the lignocellulosic feedstock to the composition in the vessel for a period of time sufficient to remove at least 80% of the lignin from the lignocellulosic feedstock;

optionally, separating and removing a liquid phase comprising dissolved lignin fragments from a solid phase comprising cellulose fibres.