CN113999358B - Preparation method of urea formaldehyde pre-shrinking liquid for formaldehyde production chipboard - Google Patents
Preparation method of urea formaldehyde pre-shrinking liquid for formaldehyde production chipboard Download PDFInfo
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- CN113999358B CN113999358B CN202111392162.0A CN202111392162A CN113999358B CN 113999358 B CN113999358 B CN 113999358B CN 202111392162 A CN202111392162 A CN 202111392162A CN 113999358 B CN113999358 B CN 113999358B
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- Prior art keywords
- formaldehyde
- ufc
- urea
- final
- tail gas
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- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 title claims abstract description 125
- 229920001807 Urea-formaldehyde Polymers 0.000 title claims abstract description 30
- ODGAOXROABLFNM-UHFFFAOYSA-N polynoxylin Chemical compound O=C.NC(N)=O ODGAOXROABLFNM-UHFFFAOYSA-N 0.000 title claims abstract description 30
- 239000007788 liquid Substances 0.000 title claims abstract description 19
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- 238000004519 manufacturing process Methods 0.000 title abstract description 5
- 239000011093 chipboard Substances 0.000 title abstract description 4
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims abstract description 20
- 239000004202 carbamide Substances 0.000 claims abstract description 20
- 229920000877 Melamine resin Polymers 0.000 claims abstract description 9
- 238000010521 absorption reaction Methods 0.000 claims abstract description 9
- JDSHMPZPIAZGSV-UHFFFAOYSA-N melamine Chemical compound NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 claims abstract description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 24
- 238000000034 method Methods 0.000 claims description 8
- YNAVUWVOSKDBBP-UHFFFAOYSA-N Morpholine Chemical compound C1COCCN1 YNAVUWVOSKDBBP-UHFFFAOYSA-N 0.000 claims description 4
- NQRYJNQNLNOLGT-UHFFFAOYSA-N Piperidine Chemical compound C1CCNCC1 NQRYJNQNLNOLGT-UHFFFAOYSA-N 0.000 claims description 4
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 claims description 4
- 239000003513 alkali Substances 0.000 claims description 3
- 150000007530 organic bases Chemical class 0.000 claims description 3
- 239000002245 particle Substances 0.000 claims description 3
- 238000003860 storage Methods 0.000 claims description 3
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 2
- 239000003054 catalyst Substances 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 claims description 2
- 238000012432 intermediate storage Methods 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 239000007800 oxidant agent Substances 0.000 claims description 2
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 claims description 2
- 229910052709 silver Inorganic materials 0.000 claims description 2
- 239000004332 silver Substances 0.000 claims description 2
- 125000002485 formyl group Chemical class [H]C(*)=O 0.000 abstract description 14
- 238000006243 chemical reaction Methods 0.000 abstract description 10
- 230000007613 environmental effect Effects 0.000 abstract description 4
- 239000000126 substance Substances 0.000 abstract description 3
- 239000000243 solution Substances 0.000 description 15
- 239000008098 formaldehyde solution Substances 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 6
- 239000012670 alkaline solution Substances 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 2
- 239000003292 glue Substances 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- WSFSSNUMVMOOMR-NJFSPNSNSA-N methanone Chemical compound O=[14CH2] WSFSSNUMVMOOMR-NJFSPNSNSA-N 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
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
- C08G12/26—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic compounds
- C08G12/34—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic compounds and acyclic or carbocyclic compounds
- C08G12/36—Ureas; Thioureas
- C08G12/38—Ureas; Thioureas and melamines
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J161/00—Adhesives based on condensation polymers of aldehydes or ketones; Adhesives based on derivatives of such polymers
- C09J161/20—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen
- C09J161/30—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic and acyclic or carbocyclic compounds
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- 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)
Abstract
The invention discloses a preparation method of urea formaldehyde pre-shrinking liquid for formaldehyde production chipboard, belonging to the technical field of chemical preparation, comprising the following steps: the mixed gas containing formaldehyde is absorbed by urea solution in an alkaline environment in an absorption tower to prepare UFC; the formaldehyde gas which is not completely absorbed enters an absorption two tower and is absorbed by water; the produced tail gas part enters a reactor through a mixer, and the rest is led into a tail gas processor; on the one hand, the invention keeps the proper alkalinity of the system in the preparation process of the urea formaldehyde precondensate, thereby improving the conversion rate of UFC by more than 15 percent; on the other hand, by adding a proper amount of melamine into urea solution, the free aldehyde in UFC can be reduced by more than 30%, and when the urea solution is used for preparing a shaving board, the environmental protection performance of the prepared shaving board can reach E0 level; in addition, the tail gas is recycled, and the tail gas treatment pressure and the environmental protection pressure are reduced.
Description
Technical Field
The invention relates to the technical field of chemical preparation, in particular to a preparation method of urea formaldehyde pre-shrinking liquid for producing shaving boards by formaldehyde.
Background
The urea formaldehyde pre-shrinking liquid (UFC) is a main production raw material of urea formaldehyde glue, is an environment-friendly chemical product, and is especially widely applied to the process of glue preparation of artificial boards. The preparation of the urea formaldehyde precondensate well solves the problem of formaldehyde storage and transportation in cold winter.
There have been many reports on the preparation of urea formaldehyde precondensate, and the preparation method is generally to absorb a mixed gas containing formaldehyde and a solution containing urea.
The current method for preparing urea formaldehyde precondensate generally has the following problems: 1. the conversion rate of the urea formaldehyde precondensate is lower, generally about 75%; 2. the free aldehyde content in the obtained urea formaldehyde precondensate is relatively high, generally about 5%.
Disclosure of Invention
The invention aims to provide a preparation method of urea formaldehyde pre-shrinking liquid for producing shaving boards by formaldehyde, so as to solve the problems.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: a preparation method of urea formaldehyde pre-shrinking liquid for formaldehyde production chipboard comprises the following steps:
(1) The mixed gas containing formaldehyde is absorbed by urea solution in an alkaline environment in an absorption tower to prepare UFC;
(2) The formaldehyde gas which is not completely absorbed in the step (1) enters an absorption two tower and is absorbed by water;
(3) And (3) feeding part of the tail gas produced in the step (2) into a reactor through a mixer, and feeding the rest into a tail gas processor.
A large number of experiments prove that the conversion rate of UFC can be obviously improved by keeping the proper alkalinity of the system in the preparation process of urea formaldehyde pre-shrinking liquid.
The preferable technical scheme also comprises the step (4) that the finished product UFC is extracted from a tower kettle, enters an intermediate storage tank first, is uniformly mixed after being analyzed to be qualified, and is sent into a finished product storage tank.
As a preferred technical scheme, in the step (1), the preparation method of the formaldehyde-containing mixed gas comprises the following steps:
s1: introducing methanol and air into an evaporator;
s3: methanol and air are mixed, evaporated and passed into a superheater;
s3: mixing and heating methanol, air and steam in a superheater, and introducing the mixture into a filter;
s4: the methanol, air, tail gas and steam filtered by the filter enter a reactor through a mixer;
s5: the mixed gas is oxidized in an oxidizer under the action of a silver catalyst to generate the mixed gas containing formaldehyde.
As a preferred technical scheme, in the step (1), the alkaline environment means that the pH of the system is kept between 7.8 and 9.5.
As a further preferred embodiment, the alkaline environment is formed by the addition of an organic base.
The organic alkali is adopted, so that the corrosion of the alkali to the sealing of the equipment is reduced, the risk of accidental leakage is reduced, and the service life of the equipment is prolonged while the proper alkalinity of the system is maintained.
As a still further preferable embodiment, the organic base is at least one selected from piperidine, morpholine and pyridine.
As a preferred technical scheme, in the step (1), 1-3wt% of melamine is added to the urea solution based on the formaldehyde content.
A large number of experiments prove that in the preparation process of the urea formaldehyde precondensate, a proper amount of melamine is added into urea solution, so that the formaldehyde content in UFC products can be obviously reduced, and the environment friendliness of the UFC products in the process of producing the particle boards is facilitated.
Compared with the prior art, the invention has the advantages that: on the one hand, the invention keeps the proper alkalinity of the system in the preparation process of the urea formaldehyde precondensate, thereby improving the conversion rate of UFC to 93%; on the other hand, by adding a proper amount of melamine into urea solution, the free formaldehyde in UFC can be reduced to 1.5% from the conventional 5%, and when the urea solution is used for preparing a shaving board, the environmental protection performance of the prepared shaving board can reach E0 level (the release amount of E0 formaldehyde is less than or equal to 0.5mg/L, the release amount of E1 level formaldehyde is 0.5 mg/I-1.5 mg/L, and the release amount of E2 level formaldehyde is more than 1.5 mg/L); in addition, the tail gas is recycled, and the tail gas treatment pressure and the environmental protection pressure are reduced.
Detailed Description
The invention will be further illustrated with reference to examples.
Example 1:
the yield of the formaldehyde device is controlled at 120t/d, two-tower diluted aldehyde is taken into a diluted aldehyde tank (used for preparing urea solution and solving the problem of the balance of the diluted aldehyde of the system), the concentration of formaldehyde on-line products is increased to 53 percent, and diluted alkaline solution (20 weight percent) is added into the middle section and the lower section of the absorption tower to adjust the PH value of the formaldehyde solution to 9.3; adding 2wt% of melamine into urea solution based on formaldehyde content, adding the prepared 65wt% urea solution into the upper section of a tower to react with formaldehyde solution, controlling the temperature of the tower bottom at 83-85 ℃, and operating for 8 hours to obtain urea formaldehyde pre-shrinking liquid (UFC) with total content of 74.5%, UFC conversion rate of 93%, free aldehyde content of 1.5%, and colorless, clear and transparent product appearance.
Example 2:
the yield of the formaldehyde device is controlled at 120t/d, two-tower diluted aldehyde is taken into a diluted aldehyde tank (used for preparing urea solution and solving the problem of the balance of the diluted aldehyde of the system), the concentration of formaldehyde on-line products is increased to 53 percent, and diluted alkaline solution (20 weight percent) is added into the middle section and the lower section of the absorption tower to adjust the PH value of the formaldehyde solution to 8.7; adding 2wt% of melamine into the urea solution based on the formaldehyde content, adding the prepared 65wt% urea solution into the upper section of a tower to react with the formaldehyde solution, controlling the temperature of the tower bottom at 83-85 ℃, and operating for 8 hours to obtain urea formaldehyde pre-shrinking liquid (UFC) with the total content of about 74.3%, wherein the conversion rate of the UFC is 92.8%, the free aldehyde content is 1.5%, and the product has colorless, clear and transparent appearance.
Example 3
The yield of the formaldehyde device is controlled at 120t/d, two-tower diluted aldehyde is taken into a diluted aldehyde tank (used for preparing urea solution and solving the problem of the balance of the diluted aldehyde of the system), the concentration of formaldehyde on-line products is increased to 53 percent, and diluted alkaline solution (20 weight percent) is added into the middle section and the lower section of the absorption tower to adjust the PH value of the formaldehyde solution to 9.3; adding 1wt% of melamine into the urea solution based on the formaldehyde content, adding the prepared 65wt% urea solution into the upper section of a tower to react with the formaldehyde solution, controlling the temperature of the tower bottom at 83-85 ℃, and operating for 8 hours to obtain urea formaldehyde pre-shrinking liquid (UFC) with the total content of about 74.3%, wherein the conversion rate of the UFC is 92.8%, the free aldehyde content is 1.6%, and the product has colorless, clear and transparent appearance.
Comparative example 1:
in this comparative example, compared with example 1, only the pH of the formaldehyde solution was adjusted from 9.3 to 7.5, and the rest was the same as in example 1, resulting in: after 8 hours of operation, the total content of the urea formaldehyde pre-shrinking liquid (UFC) is about 65 percent, the conversion rate of the UFC is 80 percent, the free formaldehyde content of the urea formaldehyde pre-shrinking liquid (UFC) is 1.9 percent, and the product appearance is colorless.
Comparative example 2:
this comparative example was compared with example 1, and the pH of the formaldehyde solution was adjusted from 9.3 to 10, and the rest was the same as in example 1, resulting in: after 8 hours of operation, the total content of the urea formaldehyde pre-shrinking liquid (UFC) is about 71.5 percent, the conversion rate of the UFC is 89.1 percent, the free formaldehyde content of the urea formaldehyde pre-shrinking liquid (UFC) is 1.6 percent, and the product has a yellowish appearance.
Comparative example 3
This comparative example was compared with example 1, with no melamine added, and the rest was identical to example 1, with the result that: after 8 hours of operation, the total content of the urea formaldehyde pre-shrinking liquid (UFC) is about 73.5 percent, the conversion rate of the UFC is 91 percent, and the free formaldehyde content of the urea formaldehyde pre-shrinking liquid (UFC) is 6.5 percent.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.
Claims (5)
1. The preparation method of the urea formaldehyde pre-shrinking liquid for producing the shaving board by formaldehyde is characterized by comprising the following steps of:
(1) Absorbing mixed gas containing formaldehyde in an absorption tower in an alkaline environment by using urea solution, wherein the urea solution is added with 1-3wt% of melamine based on the content of formaldehyde to prepare UFC, and the alkaline environment means that the pH of the system is kept at 7.8-9.5;
(2) The formaldehyde gas which is not completely absorbed in the step (1) enters an absorption two tower and is absorbed by water;
(3) And (3) feeding part of the tail gas produced in the step (2) into a reactor through a mixer, and feeding the rest into a tail gas processor.
2. The method of claim 1, further comprising the step of (4) extracting the final UFC from a tower, feeding the final UFC into an intermediate storage tank, mixing the final UFC with the final UFC after the final UFC is qualified, and feeding the final UFC into a final storage tank.
3. The method for preparing urea formaldehyde pre-shrinking liquid for formaldehyde to produce shaving board according to claim 1, wherein in the step (1), the method for preparing the formaldehyde-containing mixed gas comprises the following steps:
s1: introducing methanol and air into an evaporator;
s3: methanol and air are mixed, evaporated and passed into a superheater;
s3: mixing and heating methanol, air and steam in a superheater, and introducing the mixture into a filter;
s4: the methanol, air, tail gas and steam filtered by the filter enter a reactor through a mixer;
s5: the mixed gas is oxidized in an oxidizer under the action of a silver catalyst to generate the mixed gas containing formaldehyde.
4. The method of producing urea formaldehyde precondensate for particle board according to claim 1, wherein the alkaline environment is formed by adding organic alkali.
5. The method for preparing urea formaldehyde precondensate for producing particle boards by formaldehyde according to claim 4, wherein the organic base is at least one selected from piperidine, morpholine and pyridine.
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| CN202111392162.0A CN113999358B (en) | 2021-11-23 | 2021-11-23 | Preparation method of urea formaldehyde pre-shrinking liquid for formaldehyde production chipboard |
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| CN202111392162.0A CN113999358B (en) | 2021-11-23 | 2021-11-23 | Preparation method of urea formaldehyde pre-shrinking liquid for formaldehyde production chipboard |
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| CN113999358B true CN113999358B (en) | 2024-02-06 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108689817A (en) * | 2018-08-01 | 2018-10-23 | 江苏道尔顿石化科技有限公司 | A kind of device and method of iron molybdenum method production formaldehyde coproduction UFC |
| CN117126357A (en) * | 2023-08-09 | 2023-11-28 | 山东联亿新能源科技股份有限公司 | Continuous high-quality ammonia aldehyde copolymer liquid production method and application |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB906120A (en) * | 1957-10-30 | 1962-09-19 | Montedison Spa | Improvements relating to concentrated urea-formaldehyde solutions |
| EP0017206A1 (en) * | 1979-04-07 | 1980-10-15 | BASF Aktiengesellschaft | Process for the simultaneous preparation of concentrated aqueous formaldehyde-urea solutions and formaldehyde solutions |
| CN105348465A (en) * | 2015-12-04 | 2016-02-24 | 广西南宁德源胶粘剂有限公司 | Preparation method of E0-grade melamine modified urea formaldehyde resin |
| CN107522604A (en) * | 2017-09-01 | 2017-12-29 | 赵达扬 | The method of ultra-large production formaldehyde and ureaformaldehyde preshrunk liquid |
| CN108689817A (en) * | 2018-08-01 | 2018-10-23 | 江苏道尔顿石化科技有限公司 | A kind of device and method of iron molybdenum method production formaldehyde coproduction UFC |
| CN110563903A (en) * | 2019-09-06 | 2019-12-13 | 无锡市华立石化工程有限公司 | preparation system and preparation process of urea formaldehyde pre-condensed liquid |
-
2021
- 2021-11-23 CN CN202111392162.0A patent/CN113999358B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB906120A (en) * | 1957-10-30 | 1962-09-19 | Montedison Spa | Improvements relating to concentrated urea-formaldehyde solutions |
| US3067177A (en) * | 1957-10-30 | 1962-12-04 | Montedison Spa | Process for producing concentrated urea-formaldehyde solutions by absorbing gaseous formaldehyde in aqueous urea solutions |
| EP0017206A1 (en) * | 1979-04-07 | 1980-10-15 | BASF Aktiengesellschaft | Process for the simultaneous preparation of concentrated aqueous formaldehyde-urea solutions and formaldehyde solutions |
| CN105348465A (en) * | 2015-12-04 | 2016-02-24 | 广西南宁德源胶粘剂有限公司 | Preparation method of E0-grade melamine modified urea formaldehyde resin |
| CN107522604A (en) * | 2017-09-01 | 2017-12-29 | 赵达扬 | The method of ultra-large production formaldehyde and ureaformaldehyde preshrunk liquid |
| CN108689817A (en) * | 2018-08-01 | 2018-10-23 | 江苏道尔顿石化科技有限公司 | A kind of device and method of iron molybdenum method production formaldehyde coproduction UFC |
| CN110563903A (en) * | 2019-09-06 | 2019-12-13 | 无锡市华立石化工程有限公司 | preparation system and preparation process of urea formaldehyde pre-condensed liquid |
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