CN1164511C - Methylene phosphonic carboxylic acid, its preparation process and its application in water treatment - Google Patents
Methylene phosphonic carboxylic acid, its preparation process and its application in water treatment Download PDFInfo
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- CN1164511C CN1164511C CNB011342013A CN01134201A CN1164511C CN 1164511 C CN1164511 C CN 1164511C CN B011342013 A CNB011342013 A CN B011342013A CN 01134201 A CN01134201 A CN 01134201A CN 1164511 C CN1164511 C CN 1164511C
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- water
- acid
- methylene phosphonic
- carboxylic acid
- phosphorus trichloride
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Abstract
The present invention relates to a water quality stabilizer of methylene phosphonic carboxylic acid, and a preparation process and the application thereof in water treatment. Carboxylic amines, phosphorus trichloride and water are firstly adopted in the preparing process of the methylene phosphonic carboxylic acid. After temperature rise, formaldehyde solution is added, or the carboxylic amines, the phosphorous acid, the concentrated hydrochloric acid and the water are firstly added. After temperature rise, the formaldehyde solution is added. The methylene phosphonic carboxylic acid prepared by the method of the present invention can reduce the generation of side products and can increase the reaction yield. The obtained product can be used as the water quality stabilizer to be applied to the industrial cycle treatment of cooling water and boiler water.
Description
Technical field
The present invention relates to the preparation method of methylene phosphonic carboxylic acid water quality stabilizer, promptly in a molecule, contain the preparation method of the water quality stabilizer of carboxylic acid group and phosphonate group (hereinafter to be referred as the phosphine carboxylic acid) simultaneously.
Background technology
In recirculating cooling water system, mainly exist fouling, corrosion and microorganism to endanger three aspect problems.And anti-locking system fouling and corrosion most convenient and effective means are to add corrosion inhibiting and descaling agent in recirculated cooling water.The at present domestic prescription that is usually used in the recirculated cooling water processing mostly is phosphorus line formulation, its host is the corrosion inhibiting and descaling agent that contains phosphonate group, they mainly comprise: 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP), Amino Trimethylene Phosphonic Acid (ATMP), ethylene diamine tetra methylene phosphonic acid (EDTMPS), phosphono-containing butane-1,2,4-tricarboxylic acid (PBTCA), 2-hydroxyl phosphino-acetate (HPA) etc.Along with production-scale continuous expansion, the process water problem becomes the principal element of restriction production development gradually.Except that national macro adjustments and controls, reasonable disposition to water resources, the enterprises water saving is nothing more than two kinds of main paties, be the raising and the reuse of sewage in recirculating cooling water system of recirculating cooling water system cycles of concentration, and the smooth implementation of these two kinds water saving schemes must be based upon on the basis of water conditioning.Therefore developing new and effective water quality stabilizer becomes the key that addresses the above problem.
Methylene phosphonic carboxylic acid is a kind of water quality stabilizer of excellent property, and its characteristics are for to contain carboxylic acid group and phosphonate group simultaneously in a molecule, and its preparation method commonly used has two kinds:
The first is simultaneously soluble in water with carboxylic amine and formaldehyde (HCHO) solution, adds phosphorus trichloride (PCl afterwards again
3) react methylene phosphonic carboxylic acid.
It two is that carboxylic amine, phosphorous acid and formaldehyde solution is simultaneously soluble in water, add again concentrated hydrochloric acid react methylene phosphonic carboxylic acid.
(Nanjing College of Architectural Engineering's journal 2000 such as Zhang Jun, Ma Jiaxiang, 52 (1): 48-51) disclose a kind of novel corrosion-retarding Scale inhibitors GDMP (glycine two methene phosphonic acids), its preparation method is as follows: add the hydrochloric acid soln of the aqueous solution of a certain amount of 36% formaldehyde and a small amount of 36-38% in an amount of glycine after, be controlled under the suitable temperature, drip phosphorus trichloride, after treating fully reaction, separate out GDMP with the acetone crystallization.In entire reaction course, the HCl gas of reaction being emitted with rubber tubing causes outdoor or is reclaimed.Crystallized product is carried out recrystallization, obtain purer product after suction filtration, washing, drying, productive rate is 76.4%.The glycine two methene phosphonic acids of gained are the amino methane phosphonic acids that has a hydroxy-acid group, are a kind of corrosion inhibiting and descaling agents of excellent performance, and its scale-inhibiting properties is better than ATMP.GMDP and Zn
2+Interionic exists very obvious synergistic effect, and corrosion inhibition rate is up to 96.3% during composite use.Productive rate was lower when its shortcoming was with method for preparing GDMP.
The contriver discovers: the back adds formaldehyde solution can obtain methylene phosphonic carboxylic acid with higher yield.
Summary of the invention
The object of the present invention is to provide a kind of preparation method of methylene phosphonic carboxylic acid.Prepare the generation that methylene phosphonic carboxylic acid can reduce by product with method of the present invention, improve reaction yield.
To achieve the above object of the invention, the present invention adopts when the preparation methylene phosphonic carboxylic acid and adds carboxylic amine (preferred amino acid), phosphorus trichloride and water earlier, after the intensification, adds formaldehyde solution again; Perhaps add carboxylic amine (preferred amino acid), phosphorous acid, concentrated hydrochloric acid and water earlier, after the intensification, add formaldehyde solution again.
The invention provides a kind of preparation method of methylene phosphonic carboxylic acid, comprise carboxylic amine (preferred amino acid) soluble in water, add phosphorus trichloride down at 10-30 ℃, controlled temperature is not higher than 60 ℃, treat to be warming up to again after phosphorus trichloride adds 60-110 ℃, preferred 80-100 ℃, more preferably after 90-95 ℃, add formaldehyde solution, and, obtain methylene phosphonic carboxylic acid in 60-110 ℃, preferred 80-100 ℃, more preferably 90-95 ℃ of reaction 2-12 hour down, preferred 3-10 hour.The mole proportioning of raw material is: carboxylic amine/formaldehyde/phosphorus trichloride=1/ (1-3)/(1-2).
The present invention also provides a kind of preparation method of methylene phosphonic carboxylic acid, comprise carboxylic amine (preferred amino acid), phosphorous acid soluble in water, add concentrated hydrochloric acid down at 10-30 ℃, controlled temperature is not higher than 60 ℃, treat to be warming up to again after concentrated hydrochloric acid adds 60-110 ℃, preferred 80-100 ℃, more preferably after 90-95 ℃, add formaldehyde solution, and, obtain methylene phosphonic carboxylic acid in 60～110 ℃, preferred 80-100 ℃, more preferably 90-95 ℃ of reaction 2-12 hour down, preferred 3-10 hour.The mole proportioning of raw material is: carboxylic amine/formaldehyde/phosphorous acid=1/ (1-3)/(1-2), the purpose that concentrated hydrochloric acid adds is to carry out in order to make to be reflected under the acidic conditions, its consumption is not particularly limited, and its add-on is 0.5-2 with hydrogenchloride and amino acid whose mol ratio preferably.
The methylene phosphonic carboxylic acid water quality stabilizer that obtains with the inventive method contains carboxylic acid group and phosphonate group simultaneously in a molecule, its general formula can be expressed as: RCH (COOH) N (CH
2PO
3H
2)
2, RCH wherein
2(COOH) N is from amino acid.Described amino acid is selected from glycine, L-glutamic acid, L-Ala, Xie Ansuan, leucine, Isoleucine, Serine, Threonine, halfcystine, methionine(Met), aspartic acid, phenylalanine, tyrosine.
Methene type water quality stabilizer of the present invention can make with prior art disclosed method, and also available method of the present invention makes, and preferentially selects for use method of the present invention to make, and to reduce by product, improves product yield.
Has good resistance CaCO with method synthetic methylene phosphonic of the present invention acid
3And Ca
3(PO
4)
2Dirt ability, the Zn in the stabilize water effectively
2+With dispersion Fe
2O
3, have certain corrosion inhibition concurrently.Therefore can be used as anti-incrustation corrosion inhibitor and be widely used in recirculated cooling water, the boiler water processing.
Embodiment
Embodiment 1
In four neck flasks of agitator, reflux exchanger, constant pressure funnel and thermometer are housed, add 73.57g (0.5mol) L-glutamic acid and 70mL water, start stirring, L-glutamic acid is fully dissolved.Under room temperature (20 ℃), in bottle, slowly drip 137.5g (1.0mol) phosphorus trichloride, drip off in the control 2h, and keep the temperature in the four neck flasks not to be higher than 60 ℃ with cooling bath.Treat that phosphorus trichloride dropwises, be warming up to 90 ℃, in bottle, drip 121.6g (1.5mol) formaldehyde solution, keep 90-95 ℃ of reaction of temperature 4h, till not having hydrogenchloride and emitting from the reflux cooler upper end.Cool off L-glutamic acid two methene phosphonic acids (EDMP) aqueous solution, concentrate and under the effect of methyl alcohol, separate out the EDMP160.0 gram, product yield is 95.5%.
Embodiment 2
Except that the reaction times is the 7h, all the other conditions the results are shown in table 1 with embodiment 1.
Embodiment 3
Except that the reaction times is the 10h, all the other conditions the results are shown in table 1 with embodiment 1.
Embodiment 4
Except that temperature of reaction is 70-75 ℃, all the other conditions the results are shown in table 1 with embodiment 1.
Embodiment 5
Except that temperature of reaction is 80-85 ℃, all the other conditions the results are shown in table 1 with embodiment 1.
Embodiment 6
Except that proportioning raw materials L-glutamic acid/formaldehyde/phosphorus trichloride is 1/1/1, all the other conditions the results are shown in table 1 with embodiment 1.
Embodiment 7
Except that proportioning raw materials L-glutamic acid/formaldehyde/phosphorus trichloride is 1/2/1, all the other conditions the results are shown in table 1 with embodiment 1.
Embodiment 8
Except that proportioning raw materials L-glutamic acid/formaldehyde/phosphorus trichloride is 1/2/2, all the other conditions the results are shown in table 1 with embodiment 1.
Comparative Examples 1
In four neck flasks of agitator, reflux exchanger, constant pressure funnel and thermometer are housed, add 73.57g (0.5mol) L-glutamic acid, 121.6g (1.5mol) formaldehyde and 70mL water, start stirring, L-glutamic acid is fully dissolved.Under room temperature (20 ℃), in bottle, slowly drip 137.5g (1.0mol) phosphorus trichloride, drip off in the control 2h, and keep the temperature in the four neck flasks not to be higher than 60 ℃ with cooling bath.Treat that phosphorus trichloride dropwises, be warming up to 90 ℃, keep 90～95 ℃ of reactions of temperature 4h, till not having hydrogenchloride and emitting from the reflux cooler upper end.Cool off L-glutamic acid two methene phosphonic acids (EDMP) aqueous solution, concentrate and under the effect of methyl alcohol, separate out the EDMP147.9 gram, product yield is 88.3%.
Table 1
| Embodiment | L-glutamic acid/formaldehyde/phosphorus trichloride (mol ratio) | Temperature (℃) | Reaction times (h) | Productive rate (%) |
| 1 | 1/3/2 | 90-95℃ | 4 | 95.5 |
| 2 | 1/3/2 | 90-95℃ | 7 | 95.4 |
| 3 | 1/3/2 | 90-95℃ | 10 | 95.1 |
| 4 | 1/3/2 | 70-75℃ | 4 | 93.9 |
| 5 | 1/3/2 | 80-85℃ | 4 | 94.3 |
| 6 | 1/1/1 | 90-95℃ | 4 | 94.9 |
| 7 | 1/2/1 | 90-95℃ | 4 | 94.7 |
| 8 | 1/2/2 | 90-95℃ | 4 | 95.3 |
| Comparative Examples 1 | 1/3/2 | 90-95℃ | 4 | 88.3 |
Embodiment 9
In four neck flasks of agitator, reflux exchanger, constant pressure funnel and thermometer are housed, add 37.54g (0.5mol) glycine, 82g (1.0mol) phosphorous acid and 50mL water, start stirring, solid is fully dissolved.Under room temperature (20 ℃), slow Dropwise 5 0mL concentrated hydrochloric acid in bottle drips off in the control 2h, and keeps the temperature in the four neck flasks not to be higher than 60 ℃ with cooling bath.Treat that concentrated hydrochloric acid dropwises, be warming up to 90 ℃, in bottle, drip 121.6g (1.5mol) formaldehyde solution, keep 90-95 ℃ of reaction of temperature 4h, till not having hydrogenchloride and emitting from the reflux cooler upper end.Cool off glycine two methene phosphonic acids (GDMP) aqueous solution, concentrate and under the effect of methyl alcohol, separate out the GDMP127.3 gram, product yield is 96.8%.
Embodiment 10
Except that the reaction times is the 7h, all the other conditions the results are shown in table 2 with embodiment 9.
Embodiment 11
Except that the reaction times is the 10h, all the other conditions the results are shown in table 2 with embodiment 9.
Embodiment 12
Except that temperature of reaction is 70-75 ℃, all the other conditions the results are shown in table 2 with embodiment 9.
Embodiment 13
Except that temperature of reaction is 80-85 ℃, all the other conditions the results are shown in table 2 with embodiment 9.
Embodiment 14
Except that proportioning raw materials glycine/formaldehyde/phosphorous acid is 1/1/1, all the other conditions the results are shown in table 2 with embodiment 9.
Embodiment 15
Except that proportioning raw materials glycine/formaldehyde/phosphorous acid is 1/2/1, all the other conditions the results are shown in table 2 with embodiment 9.
Embodiment 16
Except that proportioning raw materials glycine/formaldehyde/phosphorous acid is 1/2/2, all the other conditions the results are shown in table 2 with embodiment 9.
Comparative Examples 2
In being housed, four neck flasks of agitator, reflux exchanger, constant pressure funnel and thermometer add 37.54g (0.5mol) glycine, 82g (1.0mol) phosphorous acid, 121.6g (1.5mol) formaldehyde solution and 50mL water, start stirring, solid is fully dissolved.Under room temperature (20 ℃), slow Dropwise 5 0mL concentrated hydrochloric acid in bottle drips off in the control 2h, and keeps the temperature in the four neck flasks not to be higher than 60 ℃ with cooling bath.Treat that concentrated hydrochloric acid dropwises, be warming up to 90 ℃, keep 90～95 ℃ of reactions of temperature 4h, till not having hydrogenchloride and emitting from the reflux cooler upper end.Cool off glycine two methene phosphonic acids (GDMP) aqueous solution, concentrate and under the effect of methyl alcohol, separate out the GDMP117.2 gram, product yield is 89.1%.
Table 2
| Embodiment | Glycine/formaldehyde/phosphorous acid (mol ratio) | Temperature (℃) | Reaction times (h) | Productive rate (%) |
| 9 | 1/3/2 | 90-95℃ | 4 | 96.8 |
| 10 | 1/3/2 | 90-95℃ | 7 | 96.5 |
| 11 | 1/3/2 | 90-95℃ | 10 | 96.4 |
| 12 | 1/3/2 | 70-75℃ | 4 | 95.0 |
| 13 | 1/3/2 | 80-85℃ | 4 | 95.2 |
| 14 | 1/1/1 | 90-95℃ | 4 | 96.3 |
| 15 | 1/2/1 | 90-95℃ | 4 | 96.4 |
| 16 | 1/2/2 | 90-95℃ | 4 | 96.5 |
| Comparative Examples 2 | 1/3/2 | 90-95℃ | 4 | 89.1 |
Embodiment 17
In four neck flasks of agitator, reflux exchanger, constant pressure funnel and thermometer are housed, add 44.5g (0.5mol) L-Ala and 70mL water, start stirring, L-Ala is fully dissolved.Under room temperature (20 ℃), in bottle, slowly drip 137.5g (1.0mol) phosphorus trichloride, drip off in the control 2h, and keep the temperature in the four neck flasks not to be higher than 60 ℃ with cooling bath.Treat that phosphorus trichloride dropwises, be warming up to 90 ℃, in bottle, drip 121.6g (1.5mol) formaldehyde solution, keep 90-95 ℃ of reaction of temperature 4h, till not having hydrogenchloride and emitting from the reflux cooler upper end.Cool off the L-Ala two methene phosphonic acids aqueous solution, concentrate and under the effect of methyl alcohol, separate out L-Ala two methene phosphonic acids 133.7 grams, product yield is 96.5%.
Embodiment 18
In four neck flasks of agitator, reflux exchanger, constant pressure funnel and thermometer are housed, add 66.6g (0.5mol) aspartic acid and 70mL water, start stirring, aspartic acid is fully dissolved.Under room temperature (20 ℃), in bottle, slowly drip 137.5g (1.0mol) phosphorus trichloride, drip off in the control 2h, and keep the temperature in the four neck flasks not to be higher than 60 ℃ with cooling bath.Treat that phosphorus trichloride dropwises, be warming up to 90 ℃, in bottle, drip 121.6g (1.5mol) formaldehyde solution, keep 90-95 ℃ of reaction of temperature 4h, till not having hydrogenchloride and emitting from the reflux cooler upper end.Cool off the aspartic acid two methene phosphonic acids aqueous solution, concentrate and under the effect of methyl alcohol, separate out aspartic acid two methene phosphonic acids 152.0 grams, product yield is 94.7%.
Embodiment 19
With amino acid is the scale-inhibiting properties of the methylene phosphonic sour water matter stablizer of raw material
Table 3-table 5 is the static state resistance CaCO that example has been enumerated the methylene phosphonic sour water matter stablizer that is raw material with amino acid with glycine two methene phosphonic acids and L-glutamic acid two methene phosphonic acids
3And Ca
3(PO
4)
2The dirt performance, and contrast with other anti-incrustation corrosion inhibitor commonly used.
The resistance CaCO of table 3GDMP and EDMP
3The dirt performance
Test conditions: [Ca
2+]=250mgL
-1[HCO
3 -]=250mgL
-180 ± 1 ℃ of test temperatures; Concentrate 2.0 times.
The resistance CaCO of table 4GDMP, EDMP and Scale inhibitors commonly used
3The dirt performance relatively
Medicament title scale inhibition performance/%
Concentrate 2.0 times and concentrate 3.0 times concentrated 4.0 times
HEDP 60.8 32.2 28.5
PBTCA 91.6 48.7 43.5
HPA 78.4 35.7 31.2
EDTMPS 85.3 42.0 40.8
ATMP 62.5 38.4 32.2
GDMP 93.6 48.0 41.1
EDMP 96.0 55.3 46.6
Test conditions: [Ca
2+]=250mgL
-1[HCO
3 -]=250mgL
-180 ± 1 ℃ of test temperatures; Concentration 10mgL
-1
The resistance Ca of table 5GDMP and EDMP
3(PO
4)
2The dirt performance
Test conditions: [Ca
2+]=250mgL
-1[PO
4 3-]=5mgL
-180 ± 1 ℃ of test temperatures
Claims (4)
1, a kind of preparation method of methylene phosphonic carboxylic acid, comprise carboxylic amine soluble in water, add phosphorus trichloride down at 10-30 ℃, controlled temperature is not higher than 60 ℃, treat to be warming up to 60-110 ℃ again after phosphorus trichloride adds, add formaldehyde solution, and, obtain methylene phosphonic carboxylic acid in 60-110 ℃ of reaction 2-12 hour.
2, preparation method according to claim 1 is characterized in that the mole proportioning of raw material is: carboxylic amine/formaldehyde/phosphorus trichloride=1/ (1～3)/(1～2).
3, a kind of preparation method of methylene phosphonic carboxylic acid, comprise carboxylic amine, phosphorous acid soluble in water, add concentrated hydrochloric acid down at 10-30 ℃, controlled temperature is not higher than 60 ℃, treat to be warming up to 60-110 ℃ again after concentrated hydrochloric acid adds, add formaldehyde solution, and, obtain methylene phosphonic carboxylic acid in 60～110 ℃ of reactions 2-12 hour.
4, preparation method according to claim 3, the mole proportioning of raw material is: carboxylic amine/formaldehyde/phosphorous acid=1/ (1-3)/(1-2).
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|---|---|---|---|
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|---|---|---|---|
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| Publication number | Priority date | Publication date | Assignee | Title |
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| EP1887011A1 (en) * | 2006-08-09 | 2008-02-13 | Thermphos Trading GmbH | Alpha amino acid phosphonic acid compounds, method of preparation and use thereof |
| CN102399019A (en) * | 2010-09-09 | 2012-04-04 | 中国石油化工股份有限公司 | Reverse osmosis membrane scale inhibitor and application |
| CN104072653A (en) * | 2014-07-14 | 2014-10-01 | 山东省泰和水处理有限公司 | Polypropylene methylenephosphonic acid and preparation method thereof |
| CN105000686B (en) * | 2015-07-09 | 2017-03-29 | 潍坊友容实业有限公司 | A kind of salt-soda soil sprinkling irrigation equipment special anti-corrosion antisludging agent and preparation method thereof |
| CN105622955B (en) * | 2016-02-29 | 2018-11-23 | 衡阳师范学院 | A kind of soil passivation renovation agent and preparation method thereof |
| CN108301006A (en) * | 2018-03-12 | 2018-07-20 | 无锡市锡东橡塑机械有限公司 | A kind of steel band continuous degreasing water for cleaning matter stabilizer and its application method |
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