Ammonia and ammonium hydroxide stabilizers for paraformaldehyde
AssigneeCelanese International Corporation
InventorsJohn Leslie Ray, Jr., Kenneth Allen Windhorst, Martin Dominic Mancha
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Abstract
A process for forming stabilizing paraformaldehyde can include heating a formaldehyde solution comprising 30 wt % or more formaldehyde to a temperature ranging from about 70° C. to about 130° C.; aging the formaldehyde solution for a sufficient amount of time to polymerize the formaldehyde and form paraformaldehyde; solidifying the paraformaldehyde; and contacting the formaldehyde solution before and/or during heating, the formaldehyde solution during aging, the paraformaldehyde, and/or the solidified paraformaldehyde with an ammonia and/or ammonia hydroxide stabilizer.
Claims18
A process comprising:
- heating a formaldehyde solution comprising 30 wt % or more formaldehyde and about 50 ppm to about 1000 ppm of an ammonia and/or ammonia hydroxide stabilizer to a temperature ranging from about 70° C. to about 130° C.;
- aging the formaldehyde solution for a sufficient amount of time to polymerize the formaldehyde and form paraformaldehyde;
- and
- solidifying the paraformaldehyde.
A process comprising:
- exposing solidified paraformaldehyde to a gas comprising about 50 ppm to about 1000 ppm of an ammonia and/or ammonium hydroxide stabilizer.
A process comprising:
- heating a formaldehyde solution comprising 30 wt % or more formaldehyde to a temperature ranging from about 70° C. to about 130° C.;
- aging the formaldehyde solution in the presence of about 50 ppm to about 1000 ppm of an ammonia and/or ammonia hydroxide stabilizer for a sufficient amount of time to polymerize the formaldehyde and form paraformaldehyde;
- and
- solidifying the paraformaldehyde.
Dependencies are inferred from the claim text.