CN1261376C - Polyepoxysuccinic acid as environment protecting scale inhibitor and its prepn process - Google Patents
Polyepoxysuccinic acid as environment protecting scale inhibitor and its prepn process Download PDFInfo
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- CN1261376C CN1261376C CN 02111414 CN02111414A CN1261376C CN 1261376 C CN1261376 C CN 1261376C CN 02111414 CN02111414 CN 02111414 CN 02111414 A CN02111414 A CN 02111414A CN 1261376 C CN1261376 C CN 1261376C
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- maleic anhydride
- temperature
- scale inhibitor
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- environment protecting
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Abstract
The present invention relates to polyepoxy succinic acid as an environmental protection type scale inhibitor which is a homopolymer with ether bonds and carboxyl groups, and a preparation method thereof. Experiments prove that because the ether bonds and the carboxyl groups are introduced into the molecule structure, the environmental protection type scale inhibitor of the present invention has good dispersing cavity for various kinds of scale, high tolerance for calcium ions (1000 ppm), good stabilization for iron and zinc, and strong heat resistance. In the preparation method, through basic hydrolysis, maleic anhydride is epoxidated to form epoxy succinic acid; then, the polyepoxy succinic acid is formed by an ionic polymerization way under the condition with base.
Description
Technical field
The invention belongs to chemical technology field, be specifically related to a kind of Scale inhibitors polyepoxysuccinic acid and preparation method thereof, this Scale inhibitors is a kind of low molecular mass homopolymers of without phosphorus no nitrogen, belongs to the environment-friendly Scale inhibitors, and the scale inhibition that is used for water quality is handled.
Background technology
As industrial circulating cooling water, oiler feed, papermaking, petroleum industry, sea water desalinization etc., fouling all can bring serious consequence to production in relating to the every field of water treatment, reduces throughput, even causes shut-down.For example in industrial circulating cooling water system, CaCO
3Be that the most common dirt usually causes the fouling of equipment pipe internal surface, influence flowing and heat transfer efficiency of water, serious also can cause line clogging, causes shut-down.In paper industry, CaCO
3, BaSO
4Be pulp digester, give birth to the liquid pipeline, drift dirt common in device and the extraction element, the formation of these dirts increases steam consumption, reduction is given birth to liquid and flowed, increases the saltcake loss ducted, and then reduction quality product and throughput.In petroleum industry, CaCO
3, CaSO
4, BaSO
4Be the main component of dirt, can cause the decline of throughput.In the saturating desalination of seawater reverse osmosis, CaSO
4, BaSO
4, SrSO
4Be the main component of dirt, these dirts can stop up film, cause that membrane flux reduces, and throughput descends, and membrane lifetime shortens, and increases production cost, and serious also can causing produced and stopped work.Therefore the processing of the scale inhibition of service water is the research topic that people paid close attention to always.Utilization adds Scale inhibitors, and to carry out that scale inhibition handles be convenient relatively in numerous method of scale inhibition and a kind of method efficiently.
Inorganic polyphosphate-organic phosphoric acid (salt)-polycarboxylic acid-binary and the phosphorous multipolymer of ternary and binary and the not phosphorous multipolymer several stages of ternary have been experienced in the development of Scale inhibitors, and the non-phosphorus scale agent will be a developing direction from now on.Inorganic polyphosphate class Scale inhibitors such as tripolyphosphate, hexa metaphosphoric acid can suppress the formation of these dirts well, but inorganic polyphosphate very easily is hydrolyzed to orthophosphoric acid salt, the result of use of these Scale inhibitorss can not only be reduced, and, also not too serious CaCO can be made if control is improper
3The dirt problem changes very serious Ca into
3(PO
4)
2The dirt problem, the rich phosphatization of water body has also limited the application of these inorganic polyphosphates in addition.The appearance of sixties Mo to early seventies organic phosphoric acid (salt) class Scale inhibitors, polycarboxylic acid such as polyacrylic acid, polymaleic acid makes mitigation and antiscaling technology obtain breakthrough progress, compare them with inorganic polyphosphate class Scale inhibitors and have good chemical stability, not facile hydrolysis, higher water temperature and the high basicity of ability, to CaCO
3Dirt has extremely good restraining effect, and for reducing the discharging of phosphorus, this this phosphorus line formulation of recirculated cooling water in period " inorganic polyphosphate-organic phosphoric acid (salt)-polyacrylic acid " has obtained using widely.But organophosphorus acids Scale inhibitors is easy and calcium ion forms insoluble organic phosphoric acid-calcium ion mixture, organophosphorus acids Scale inhibitors degradation product also can form calcium phosphate precipitation with calcium ion, polyacrylic acid also can form insoluble polyacrylic acid-calcium ion mixture with calcium ion under high-calcium ionic concentration, these insoluble mixtures and calcium phosphate precipitation not only reduce the scale inhibition effect of Scale inhibitors itself, but also induce the formation of other dirt.The phosphino-polyacrylic acid that 70 ends occur to early eighties, the phosphino-polymaleic acid, vinylformic acid/Propylene glycol monoacrylate/methyl acrylate that copolymer such as vinylformic acid/methyl acrylate and the late nineteen eighties occur, multipolymers such as terpolymer such as acrylic acid methylpropane/Hypophosporous Acid, 50 are all developed for resistance calcium phosphate, this has promoted that " organic phosphoric acid (salt)-multipolymer " phosphorus is the development of all-organic formula, but up to the early 1990s phosphorus line formulation still account for very big proportion, raising along with human environmental consciousness, environmental regulation is further strict, many countries have begun the discharging of phosphorus restriction, promoted low-phosphorous, developing rapidly of without phosphorus prescription, low-phosphorous, without phosphorus green water conditioner has become the hot subject of domestic and international water conditioner development aspect.
United States Patent (USP) US4 in the existing technology, 654,159 have proposed a kind of preparation method who prepares polyepoxysuccinic acid, maleic anhydride changes the epoxy Succinic Acid into, be polymerized to polyepoxysuccinic acid again under the effect of calcium hydroxide, the polyepoxysuccinic acid of this method preparation has its specific molecular weight and molecular weight distribution, is a kind of added ingredients as washing composition, play sequestrant, be combined into mixture with calcium magnesium in the water and improve the washing effect of washing composition.But the polyepoxysuccinic acid scale inhibition effect that should invent preparation is not really desirable.
Summary of the invention
Purpose of the present invention aims to provide a kind of without phosphorus no nitrogen environment protecting scale inhibitor and synthetic method thereof.
The without phosphorus no nitrogen environment protecting scale inhibitor that the present invention proposes, be being raw material with maleic anhydride, through after the basic hydrolysis again epoxidation form the epoxy Succinic Acid, under the alkali existence condition, form poly-epoxidation Succinic Acid then by the ionic polymerization mode, concrete steps are as follows: maleic anhydride is dissolved in the water and under agitation slow dropping sodium, make maleic anhydride change the sodium salt of toxilic acid into, control reaction temperature is 20 ℃-50 ℃; In 60 ℃-65 ℃ water-bath, be heated to 50 ℃～60 ℃ then, add the epoxidation reaction that 30% hydrogen peroxide carries out maleate, with sodium wolframate or Vanadium Pentoxide in FLAKES is catalyzer, the heat that reaction is emitted will make temperature of charge rise to 105 ℃-110 ℃, descend gradually then, when temperature of reaction is reduced to 60 ℃～70 ℃, dropping sodium solution, control pH value is 3～5.5, and is incubated 1.5～4 hours in 60 ℃-65 ℃ water-bath, gets the epoxy Succinic Acid; Carry out polyreaction then, control reaction temperature is 60 ℃-100 ℃, adds calcium hydroxide or calcium oxide, reacts 2～5 hours, and the reaction times is 2.5-3.5 hour preferably, by filtering reactant is purified, and gets polyepoxysuccinic acid solution.Its solid content is not less than 30%, is colourless or faint yellow sticking shape liquid.The size of solid content can be regulated by the content of control water.
The structure of the product polyepoxysuccinic acid that the present invention makes is:
In the formula: n is 2～8
M is H or water soluble ion Na
+, K
+, NH
4 +, Ca
2+A kind of.
Experiment finds, the transformation efficiency that the maleic anhydride basic hydrolysis changes the toxilic acid sodium salt into directly influences the epoxidation effect of epoxidation reaction.The transformation efficiency that two carboxylic acid groups are changed carboxylate salt in toxilic acid should be 60%～80%, and ie in solution pH is 5～7 o'clock, carries out epoxidation reaction again, scale inhibition effect the best of end product polyepoxysuccinic acid.Therefore the mol ratio of maleic anhydride and sodium hydroxide preferably was controlled at 1: 1.2～1: 1.6.After adding catalyzer and oxidant hydrogen peroxide in the epoxidation reaction, carrying out along with reaction, temperature rises to 105～110 ℃ about 15～30 minutes, temperature will descend gradually then, and the pH of reaction solution also will descend gradually simultaneously, when treating that temperature drops to 60 ℃～70 ℃, the sodium hydroxide solution of Dropwise 5 0% is controlled its pH again, pH is 3～5.5 in reaction, and insulation was 1.5-2.5 hour for 1.5-4 hour preferably in 60 ℃ of-65 ℃ of water-baths.
In the epoxidation reaction, the mol ratio of catalyzer sodium wolframate or Vanadium Pentoxide in FLAKES and maleic anhydride is 0.67: 1～2.53: 1 among the present invention, and the mol ratio of oxidant hydrogen peroxide and maleic anhydride is 1.0: 1～1.2: 1.
Experiment finds that the amount of temperature, time and calcium hydroxide or calcium oxide directly influences the scale inhibition effect of end product polyepoxysuccinic acid in the polyreaction.The temperature of polyreaction is 60 ℃～100 ℃ among the present invention, and preferable temperature of reaction is 80 ℃～90 ℃, and the reaction times is 2-5 hour, is preferably 2.5～3.5 hours.The mol ratio of calcium hydroxide or calcium oxide and maleic anhydride is 0.15: 1～0.23: 1.
The present invention is to CaCO
3, BaSO
4, SrSO
4Good scale inhibition effect is arranged, especially calcium is had very high tolerance, chlorine and iron ion are had tangible stability, and very strong thermotolerance is arranged, can be widely used in aspects such as recirculating cooling water system, feedwater, oil-field water, sea water desalinization.Below, will further describe positively effect of the present invention by a series of embodiment and comparative example.
In the performance test experiment, the measuring method and the method for calculation of lime carbonate, barium sulfate scale inhibition performance are as follows:
CaCO
3Static-state scale inhibition experiment: 500ml contains certain density Scale inhibitors, Ca with the deionized water preparation
2+, HCO
3 -Solution, and to regulate pH with NaOH be 8.5, places water bath with thermostatic control then, be incubated certain hour at a certain temperature after, cooling is filtered with the millipore filter of 0.22 μ m, with EDTA method mensuration Ca
2+Ionic concn is done blank assay simultaneously.
BaSO
4Static-state scale inhibition experiment: 500ml contains certain density Scale inhibitors, Ba with the deionized water preparation
2+, SO
4 2-Solution, transfer pH, place water bath with thermostatic control then, be incubated certain hour at a certain temperature after, cooling is filtered with the millipore filter of 0.22 μ m, with atomic emission spectrometry (ICP) mensuration Ba
2+Ionic concn is done blank assay simultaneously.
Scale inhibition performance=(C
i-C
Empty)/(C
0-C
Empty) * 100%
Wherein: C
iSteady concentration for calcium or barium ion in the solution after the solution thermostatically heating that adds Scale inhibitors; C
EmptyBe blank solution steady concentration of calcium or barium ion in the solution under identical condition; C
0Be calcium in the solution before the thermostatically heating or barium ion concentration.
Embodiment
Embodiment 1, in being furnished with the four neck flasks that stir prolong, stirring, thermometer, pH meter, dropping funnel, add the 50g maleic anhydride, add the 75ml water dissolution again, the aqueous sodium hydroxide solution 55g of slow Dropwise 5 0% under cooling and stirring, the temperature of control reaction makes it less than 50 ℃.In 60 ℃～65 ℃ water-bath, heat then, when temperature rises to 50 ℃～60 ℃, the hydrogen peroxide that adds catalyzer 1.8g sodium wolframate and 60g 30%, the heat that 10～20 minutes afterreactions are emitted rises sharply to 110 ℃ temperature, temperature is reduced to 65 ℃ after about 15 minutes, adding 50% aqueous sodium hydroxide solution, to regulate pH be about 5, and insulation 2 hours in 60 ℃～65 ℃ water-bath, the epoxy Succinic Acid.With temperature life to 80 ℃～90 ℃, add a certain amount of 5.0g calcium hydroxide again, reacted 2.5 hours, reactant is purified, solid content be not less than 30% colourless or faint yellow sticking shape liquid.This product is carried out the static-state scale inhibition experiment, and recording its scale inhibition performance to lime carbonate is 82%.
Embodiment 2, in being furnished with the four neck flasks that stir prolong, stirring, thermometer, pH meter, dropping funnel, add the 50g maleic anhydride, add the 75ml water dissolution again, the aqueous sodium hydroxide solution 65g of slow Dropwise 5 0% under cooling and stirring, the temperature of control reaction makes it less than 50 ℃.In 60 ℃～65 ℃ water-bath, heat then, when temperature rises to 50 ℃～60 ℃, the hydrogen peroxide that adds catalyzer 2.0g sodium wolframate and 60g 30%, the heat that 10～20 minutes afterreactions are emitted rises sharply to 110 ℃ temperature, temperature is reduced to 65 ℃ after about 15 minutes, adding 50% aqueous sodium hydroxide solution, to regulate pH be about 5, and insulation 2 hours in 60 ℃～65 ℃ water-baths, the epoxy Succinic Acid.Temperature is risen to 90 ℃ again, add a certain amount of 6.5g calcium hydroxide, reacted 2.0 hours, reactant is purified, get solid content and be not less than 30% colourless or faint yellow sticking shape liquid.This product is carried out the static-state scale inhibition experiment, and recording its scale inhibition performance to lime carbonate is 88%.
Embodiment 3, in being furnished with the four neck flasks that stir prolong, stirring, thermometer, pH meter, dropping funnel, add the 50g maleic anhydride, adding the 75ml water dissolution, the aqueous sodium hydroxide solution 65g of slow Dropwise 5 0% under cooling and stirring, the temperature of control reaction makes it less than 50 ℃.In 60 ℃～65 ℃ water-bath, heat then, when temperature rises to 50 ℃～60 ℃, the hydrogen peroxide that adds catalyzer 2.0g Vanadium Pentoxide in FLAKES and 65g 30%, the heat that 10～20 minutes afterreactions are emitted rises sharply to 110 ℃ temperature, temperature is reduced to 65 ℃ after about 15 minutes, adding 50% aqueous sodium hydroxide solution, to regulate pH be about 4, and insulation 2 hours in 60 ℃～65 ℃ water-bath, the epoxy Succinic Acid.Temperature is risen to 85 ℃ again, add a certain amount of 7.0g calcium hydroxide, reacted 2.0 hours, reactant is purified, get solid content and be not less than 30% colourless or faint yellow sticking shape liquid.This product is carried out the static-state scale inhibition experiment, and recording its scale inhibition performance to lime carbonate is 91%.
Embodiment 4, in being furnished with the four neck flasks that stir prolong, stirring, thermometer, pH meter, dropping funnel, add the 50g maleic anhydride, adding the 75ml water dissolution, the aqueous sodium hydroxide solution 65g of slow Dropwise 5 0% under cooling and stirring, the temperature of control reaction makes it less than 50 ℃.In 60 ℃～65 ℃ water-bath, heat then, when temperature rises to 50 ℃～60 ℃, the hydrogen peroxide that adds catalyzer 2.0g2.0g sodium wolframate and 65g 30%, the heat that 10～20 minutes afterreactions are emitted rises sharply to 110 ℃ temperature, temperature is reduced to 65 ℃ after about 15 minutes, adding 50% aqueous sodium hydroxide solution, to regulate pH be about 3-5, and insulation 2 hours in 60 ℃～65 ℃ water-bath, the epoxy Succinic Acid.Temperature is risen to 85 ℃ again, add a certain amount of 7.0g calcium hydroxide, reacted 2.0 hours, reactant is purified, get solid content and be not less than 30% colourless or faint yellow sticking shape liquid.This product is carried out the static-state scale inhibition experiment, and recording its scale inhibition performance to lime carbonate is 30%.
Embodiment 5, in being furnished with the four neck flasks that stir prolong, stirring, thermometer, pH meter, dropping funnel, add the 50g maleic anhydride, adding the 75ml water dissolution, the aqueous sodium hydroxide solution 65g of slow Dropwise 5 0% under cooling and stirring, the temperature of control reaction makes it less than 50 ℃.In water-bath, be heated to 60 ℃ then, the hydrogen peroxide that adds catalyzer 2.0g sodium wolframate and 60g 30%, temperature rises to 110 ℃ after 20 minutes, temperature is reduced to 65 ℃ after 15 minutes, adding 50% aqueous sodium hydroxide solution, to regulate pH be 3.5,, and in 60 ℃～65 ℃ water-bath, be incubated 2 hours, get the epoxy Succinic Acid.Temperature is risen to 85 ℃ again, add a certain amount of 7.0g calcium hydroxide, reacted 2.0 hours, reactant is purified, get solid content and be not less than 30% colourless or faint yellow sticking shape liquid.This product is carried out the static-state scale inhibition experiment, and recording its scale inhibition performance to lime carbonate is 50%.
Performance test experiment: CaCO
3The static-state scale inhibition effect
Product example 2 of the present invention is compared as follows shown in the table with the scale-inhibiting properties of domestic and international scale inhibition product.CaCO wherein
3The static-state scale inhibition experimental conditions be Ca
2+360mg/L, HCO
3 -1000mg/L, 65 ℃ of temperature, time 18hr, pH value of solution is uncomfortable; BaSO
4The static-state scale inhibition experimental conditions be Ba
2+35mg/L, SO
4 2-80mg/L, 35 ℃ of temperature, time 24hr, pH value of solution 7.0.
Table: product of the present invention compares with the scale-inhibiting properties of domestic and international scale inhibition product
| The Scale inhibitors title | To CaCO 3Scale inhibition performance (%) | To BaSO 4Scale inhibition (%) | ||
| Scale inhibitors concentration (8ppm) | Scale inhibitors concentration (12ppm) | Scale inhibitors concentration (3ppm) | Scale inhibitors concentration (5ppm) | |
| Polyepoxysuccinic acid (example 2) | 86 | 100 | 67 | 98 |
| Commercially available PBTCA | 98 | 100 | - | - |
| Aldrich Company product polyacrylic acid (molecular weight 2000) | 79 | 91 | - | - |
| Aldrich Company product horse propylene copolymer (molecular weight 2000) | 52 | 64 | - | - |
| Commercially available SHMP (Sodium hexametaphosphate 99) | 68 | 85 | 34 | 78 |
Annotate: horizontal line "-" the expression Scale inhibitors in the table does not have scale inhibition effect under this experiment condition.
Claims (7)
1. the preparation method of a without phosphorus no nitrogen environment protecting scale inhibitor, it is characterized in that with maleic anhydride be raw material, through after the basic hydrolysis again epoxidation form the epoxy Succinic Acid, under the alkali existence condition, form poly-epoxidation Succinic Acid then by the ionic polymerization mode, concrete steps are as follows: maleic anhydride is dissolved in the water, and slow dropping sodium under agitation, make maleic anhydride change the sodium salt of toxilic acid, 20 ℃～50 ℃ of control reaction temperature into; Reacting by heating liquid to 50 ℃～60 ℃ in 60 ℃～65 ℃ water-bath then, add the epoxidation reaction that 30% hydrogen peroxide carries out maleate, with sodium wolframate or Vanadium Pentoxide in FLAKES is catalyzer, the heat that reaction is emitted will make the temperature of reactant rise to 105 ℃～110 ℃, descend gradually then, when temperature of reaction is reduced to 60 ℃～70 ℃, dropping sodium solution, control pH value is 3～5.5, and is incubated 1.5～4 hours in 60 ℃～65 ℃ water temperature, gets the epoxy Succinic Acid; Carry out polyreaction then, control reaction temperature is 60 ℃～100 ℃, adds calcium hydroxide or calcium oxide, reacted 2～5 hours, and reactant was purified, get polyepoxysuccinic acid solution by filtering, its solid content is not less than 30%, is colourless or faint yellow sticking shape liquid.
2. the preparation method of environment protecting scale inhibitor according to claim 1 is characterized in that in the maleic anhydride macromolecule alkali for hydrolysis, and the mol ratio of maleic anhydride and sodium hydroxide is 1: 1.2～1: 1.6.
3. the preparation method of environment protecting scale inhibitor according to claim 1 is characterized in that in the epoxidation reaction, and the mol ratio of maleic anhydride and catalyzer sodium wolframate or Vanadium Pentoxide in FLAKES is 1: 0.67～1: 2.53.
4. the preparation method of environment protecting scale inhibitor according to claim 1 is characterized in that in the maleic anhydride macromolecule alkali for hydrolysis, and the mol ratio of maleic anhydride and oxidant hydrogen peroxide is 1: 1.0～1: 1.2.
5. the preparation method of environment protecting scale inhibitor according to claim 1, the temperature of reaction that it is characterized in that epoxidation reaction is 60 ℃～70 ℃, and pH is 4～5, and the time is 1.5～2.5 hours.
6. the preparation method of environment protecting scale inhibitor according to claim 2 is characterized in that polymeric reaction temperature is 80 ℃～90 ℃, and the time is 2.5～3.5 hours.
7. the preparation method of environment protecting scale inhibitor according to claim 1, the mol ratio that it is characterized in that maleic anhydride and calcium hydroxide or calcium oxide is 1: 0.15～1: 0.23.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02111414 CN1261376C (en) | 2002-04-18 | 2002-04-18 | Polyepoxysuccinic acid as environment protecting scale inhibitor and its prepn process |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02111414 CN1261376C (en) | 2002-04-18 | 2002-04-18 | Polyepoxysuccinic acid as environment protecting scale inhibitor and its prepn process |
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|---|---|
| CN1398798A CN1398798A (en) | 2003-02-26 |
| CN1261376C true CN1261376C (en) | 2006-06-28 |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1303058C (en) * | 2004-01-15 | 2007-03-07 | 同济大学 | Process for preparation of biodegradable corrosion-scale inhibitor amino poly-apoxysuccinic acid |
| CN100575391C (en) * | 2008-01-28 | 2009-12-30 | 同济大学 | The corrosion inhibiting and descaling agent Epoxysuccinic acid/to acid/epoxy ethylbenzene sulfonic acid copolymer and preparation method thereof |
| CN104743688B (en) * | 2015-03-31 | 2016-09-07 | 上海多佳水处理科技有限公司 | Polyepoxysuccinic acid class water treatment agent |
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2002
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