US 12,441,848 B2
Methods for the continuous polymerization of phosphate compounds to form polyphosphate compositions
Yue Liu, Marietta, GA (US); Aleksey Isarov, Kennesaw, GA (US); Robin Brumby Helms, Ranger, GA (US); Yann Charlotte Bourgeois, Nivelles (BE); James Scott Thomas, Cumming, GA (US); Christopher Lamar Duck, Canton, GA (US); and Patrick Christopher Farrell, Cartersville, GA (US)
Assigned to J.M. Huber Corporation, Atlanta, GA (US)
Filed by J.M. Huber Corporation, Atlanta, GA (US)
Filed on Feb. 19, 2024, as Appl. No. 18/444,827.
Application 18/444,827 is a continuation of application No. 17/194,373, filed on Mar. 8, 2021, granted, now 11,939,430.
Claims priority of provisional application 63/014,740, filed on Apr. 24, 2020.
Prior Publication US 2024/0191039 A1, Jun. 13, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. C08G 79/04 (2006.01); C01B 25/40 (2006.01)
CPC C08G 79/04 (2013.01) [C01B 25/40 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A process for producing a polyphosphate composition, the process comprising:
(a) continuously introducing an aqueous slurry containing from about 5 wt. % to about 50 wt. % of a phosphate compound into a polymerization vessel, the phosphate compound comprising melamine phosphate, melamine magnesium phosphate, and/or melamine zinc phosphate;
(b1) evaporating water from the aqueous slurry in a first zone of the polymerization vessel;
(b2) polymerizing the phosphate compound in a second zone of the polymerization vessel at a temperature in a range from about 250 to about 450° C. for a time period sufficient to form the polyphosphate composition; and
(c) continuously discharging the polyphosphate composition from the polymerization vessel, wherein the polyphosphate composition comprises:
at least about 8 wt. % of a polyphosphate, the polyphosphate comprising a melamine polyphosphate, a melamine poly(magnesium phosphate), and/or a melamine poly(zinc phosphate); and
less than or equal to about 35 wt. % of the phosphate compound.