GB1033043A - Process for producing paraformaldehyde - Google Patents
Process for producing paraformaldehydeInfo
- Publication number
- GB1033043A GB1033043A GB854764A GB854764A GB1033043A GB 1033043 A GB1033043 A GB 1033043A GB 854764 A GB854764 A GB 854764A GB 854764 A GB854764 A GB 854764A GB 1033043 A GB1033043 A GB 1033043A
- Authority
- GB
- United Kingdom
- Prior art keywords
- paraformaldehyde
- solution
- temperature
- precipitation
- preferred
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 229930040373 Paraformaldehyde Natural products 0.000 title abstract 11
- 229920002866 paraformaldehyde Polymers 0.000 title abstract 11
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 abstract 12
- 238000006116 polymerization reaction Methods 0.000 abstract 6
- 238000001556 precipitation Methods 0.000 abstract 6
- 239000000243 solution Substances 0.000 abstract 6
- 238000001816 cooling Methods 0.000 abstract 4
- 239000007864 aqueous solution Substances 0.000 abstract 2
- 229920000642 polymer Polymers 0.000 abstract 2
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G2/00—Addition polymers of aldehydes or cyclic oligomers thereof or of ketones; Addition copolymers thereof with less than 50 molar percent of other substances
- C08G2/08—Polymerisation of formaldehyde
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Phenolic Resins Or Amino Resins (AREA)
Abstract
Paraformaldehyde, i.e. a polymer of formaldehyde of degree of polymerization from 10 to 100, is prepared by precipitation thereof at 65 DEG C. or lower from an aqueous solution of formaldehyde of concentration between 40 and 65% and a pH of 8 to 11. The solution may be cooled from a temperature at which no appreciable polymerization occurs to 65 DEG C. or lower, the pH being adjusted to 8 to 11 before or after cooling. The preferred lower temperature is below 40 DEG C. The temperature of the solution may at first be too high for precipitation and the solution may be cooled during a first phase in such a way that before the concentration reaches the threshold value for precipitation of paraformaldehyde an amount of paraformaldehyde is formed is immediately precipitated when the concentration exceeds that value, the cooling being continued in a second phase so that further polymerization in the immediately precipitated paraformaldehyde occurs. Preferred concentrations are 40 to 60% e.g. 55 to 60%, and preferred pH values between 9 and 10. The paraformaldehyde formed may be centrifuged and washed.ALSO:Paraformaldehyde, i.e. a polymer of formaldehyde of degree of polymerization from 10 to 100 is prepared by precipitation thereof at a temperature of 65 DEG C. or lower from an aqueous solution of formaldehyde having a concentration between 40 and 65% and a pH of 8 to 11. The solution may be cooled from a temperature at which no appreciable polymerization occurs to 65 DEG C. or lower, the pH being adjusted to 8 to 11 before or after cooling. The preferred lower temperature is below 40 DEG C. The temperature of the solution may at first be too high for precipitation and the solution may be cooled during a first phase in such a way that, before the concentration reaches the threshold value for precipitation of paraformaldehyde, an amount of paraformaldehyde is formed which is immediately precipitated when the concentration exceeds that value the cooling being continued in a second phase so that further polymerization in the immediately precipitated paraformaldehyde occurs. Preferred concentrations are 40 to 60%, e.g. 55 to 60%, and preferred pH values between 9 and 10. The paraformaldehyde formed may be centrifugal and washed.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE217163 | 1963-02-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1033043A true GB1033043A (en) | 1966-06-15 |
Family
ID=20259484
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB854764A Expired GB1033043A (en) | 1963-02-28 | 1964-02-28 | Process for producing paraformaldehyde |
Country Status (2)
| Country | Link |
|---|---|
| GB (1) | GB1033043A (en) |
| NL (1) | NL6402038A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2037759A1 (en) * | 1970-07-30 | 1972-02-10 | Meissner J | Paraformaldehyde prodn - by polymerisation of formaldehyde in aqs soln with water - soluble guanidine salts as catalysts |
-
1964
- 1964-02-28 GB GB854764A patent/GB1033043A/en not_active Expired
- 1964-02-28 NL NL6402038A patent/NL6402038A/xx unknown
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2037759A1 (en) * | 1970-07-30 | 1972-02-10 | Meissner J | Paraformaldehyde prodn - by polymerisation of formaldehyde in aqs soln with water - soluble guanidine salts as catalysts |
Also Published As
| Publication number | Publication date |
|---|---|
| NL6402038A (en) | 1964-08-31 |
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