GB1517366A - Manufacture of aqueous solutions of formaldehyde and urea - Google Patents
Manufacture of aqueous solutions of formaldehyde and ureaInfo
- Publication number
- GB1517366A GB1517366A GB4357075A GB4357075A GB1517366A GB 1517366 A GB1517366 A GB 1517366A GB 4357075 A GB4357075 A GB 4357075A GB 4357075 A GB4357075 A GB 4357075A GB 1517366 A GB1517366 A GB 1517366A
- Authority
- GB
- United Kingdom
- Prior art keywords
- urea
- formaldehyde
- absorber
- stage
- solution
- 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
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
- C08G12/00—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen
- C08G12/02—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes
- C08G12/04—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with acyclic or carbocyclic compounds
- C08G12/10—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with acyclic or carbocyclic compounds with acyclic compounds having the moiety X=C(—N<)2 in which X is O, S or —N
- C08G12/12—Ureas; Thioureas
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C273/00—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
- C07C273/02—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of urea, its salts, complexes or addition compounds
- C07C273/025—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of urea, its salts, complexes or addition compounds of solutions of urea and formaldehyde
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Phenolic Resins Or Amino Resins (AREA)
Abstract
1517366 Dissolving formaldehyde in aqueous urea solution BASF AG 23 Oct 1975 [2 Nov 1974] 43570/75 Heading C3R [Also in Division C2] Formaldehyde is prepared and dissolved in urea-formaldehyde solution by oxidatively dehydrogenating methanol with air in the presence of a silver catalyst at elevated temperature and passing the product gases successively through (1) an aqueous solution of urea and formaldehyde in 1 : 2À3-5 molar ratio at pH 5-7; (2) an aqueous solution containing 25-32 wt. per cent free urea, 4-10 wt. per cent of free formaldehyde and 15-25 wt. per cent methylolureas at pH 7-8; and (3) an aqueous solution (initially of urea alone) of urea and formaldehyde in 1 : 0À05-0À4 molar ratio at pH 8-9, air supplied to the dehydrogenation being passed through the solution, or part of it, from the first stage. In a preferred embodiment, illustrated, aqueous urea solution is introduced at the head of the 3rd-stage absorber 17; part of the bottoms product in this is recycled and the rest is mixed with part of the bottoms product from the 1st-stage absorber and fed to the head of the 2nd-stage absorber 35, which may form the lower half of the column containing the 3rdstage absorber; part of the 2nd-stage bottoms is recycled and the rest passed to the head of the 1st-stage absorber 10; part of the bottoms product from this is recycled, part passed via a heat-exchanger 28 to the wash column 2, part returned to the 3rd-stage absorber and the remainder removed as product; the wash column effluent is partly recycled and partly added to the product solution removed from the 1st-stage absorber. Air passes countercurrent up the wash column 2, is mixed with methanol and water from the vaporizer 5, and fed to reactor 8; the product gases are cooled in heat exchanger 28, pass co-current down the first absorber 10 and countercurrent up the 2nd and 3rd absorbers 35 and 17; methanol is condensed from the effluent in condenser 25, separated in separator 26 and returned to vaporizer 5.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19742451990 DE2451990C3 (en) | 1974-11-02 | 1974-11-02 | Process for the preparation of concentrated, aqueous solutions of formaleyhd and urea |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1517366A true GB1517366A (en) | 1978-07-12 |
Family
ID=5929817
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB4357075A Expired GB1517366A (en) | 1974-11-02 | 1975-10-23 | Manufacture of aqueous solutions of formaldehyde and urea |
Country Status (7)
| Country | Link |
|---|---|
| JP (1) | JPS5170727A (en) |
| BE (1) | BE835105A (en) |
| DE (1) | DE2451990C3 (en) |
| FR (1) | FR2289537A1 (en) |
| GB (1) | GB1517366A (en) |
| IT (1) | IT1044595B (en) |
| NL (1) | NL7512814A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2411850A1 (en) * | 1977-12-19 | 1979-07-13 | Reichhold Chemicals Inc | Urea-formaldehyde concentrate continuous mfr. - using formaldehyde converter gases and aq. urea soln. reacting counter-current in single multiple stage absorption column |
| DE2914135A1 (en) * | 1979-04-07 | 1980-10-23 | Basf Ag | METHOD FOR THE SIMULTANEOUS PRODUCTION OF CONCENTRATED, AQUEOUS FORMALDEHYDE / UREA SOLUTIONS AND FORMALDEHYDE SOLUTIONS |
| DE3152005A1 (en) * | 1981-12-31 | 1983-07-07 | Basf Ag, 6700 Ludwigshafen | METHOD FOR PRODUCING CONCENTRATED, AQUEOUS SOLUTIONS OF FORMALDEHYDE AND UREA |
| WO2018153736A1 (en) | 2017-02-24 | 2018-08-30 | Basf Se | Silver catalyst system having a reduced pressure drop for the oxidative dehydrogenation of alcohols |
| EP3539657A1 (en) | 2018-03-14 | 2019-09-18 | Basf Se | Improved catalysts comprising silver based intermetallic compounds |
-
1974
- 1974-11-02 DE DE19742451990 patent/DE2451990C3/en not_active Expired
-
1975
- 1975-10-23 GB GB4357075A patent/GB1517366A/en not_active Expired
- 1975-10-29 IT IT2877675A patent/IT1044595B/en active
- 1975-10-31 BE BE161453A patent/BE835105A/en not_active IP Right Cessation
- 1975-10-31 FR FR7533432A patent/FR2289537A1/en active Granted
- 1975-10-31 NL NL7512814A patent/NL7512814A/en not_active Application Discontinuation
- 1975-10-31 JP JP13056975A patent/JPS5170727A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| DE2451990C3 (en) | 1981-04-09 |
| IT1044595B (en) | 1980-03-31 |
| DE2451990A1 (en) | 1976-05-13 |
| BE835105A (en) | 1976-04-30 |
| FR2289537B1 (en) | 1979-07-06 |
| DE2451990B2 (en) | 1980-07-31 |
| JPS5170727A (en) | 1976-06-18 |
| NL7512814A (en) | 1976-05-04 |
| FR2289537A1 (en) | 1976-05-28 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed | ||
| PE20 | Patent expired after termination of 20 years |
Effective date: 19951022 |