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US 4,472,552 AGranted
Continuous process for making solid, free-flowing water dispersible PVA-aldehyde reaction product
AssigneeW. R. Grace & Co.
InventorJohn J. Blouin
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Abstract
A polyvinyl alcohol-aldehyde reaction product is produced continuously in a rotating contactor by contacting solid particles of the polyvinyl alcohol with the aldehyde in an acidic aqueous salt solution. The product can be dried and then sieved to remove oversize particles. A preferred aldehyde is either formaldehyde or glutaraldehyde which reacts with the polyvinyl alcohol to produce a reaction product that can be used as a fluid loss control agent in oil fields.
Claims18
A process for the continuous production of a polyvinyl alcohol-aldehyde reaction product comprising
- (a) adding to a rotating continuous reactor to form a mixture
- (i) solid particles of polyvinyl alcohol,
- (ii) an aldehyde, and
- (iii) an aqueous salt solution adjusted to have an acidic pH;
- (b) mixing the mixture of step (a) in the reactor until a polyvinyl alcohol-aldehyde reaction product is obtained;
- and
- (c) drying the polyvinyl alcohol-aldehyde material.
4 more elements
Dependencies are inferred from the claim text.