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WO1997016464A1 - Utilisation de semi-amides d'acides polycarboxyliques comme agents antitartre - Google Patents

Utilisation de semi-amides d'acides polycarboxyliques comme agents antitartre Download PDF

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Publication number
WO1997016464A1
WO1997016464A1 PCT/EP1996/004561 EP9604561W WO9716464A1 WO 1997016464 A1 WO1997016464 A1 WO 1997016464A1 EP 9604561 W EP9604561 W EP 9604561W WO 9716464 A1 WO9716464 A1 WO 9716464A1
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WO
WIPO (PCT)
Prior art keywords
anhydride
maleic anhydride
scale inhibitors
polycarboxylic acid
acids
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.)
Ceased
Application number
PCT/EP1996/004561
Other languages
German (de)
English (en)
Inventor
Norbert Greif
Birgit Potthoff-Karl
Knut Oppenländer
Michael Ehle
Günter OETTER
Wilhelmus Slotman
Karl-Heinz Büchner
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BASF SE
Original Assignee
BASF SE
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from DE1995140090 external-priority patent/DE19540090A1/de
Priority claimed from DE1995148318 external-priority patent/DE19548318A1/de
Application filed by BASF SE filed Critical BASF SE
Publication of WO1997016464A1 publication Critical patent/WO1997016464A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F8/00—Chemical modification by after-treatment
    • C08F8/30—Introducing nitrogen atoms or nitrogen-containing groups
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F5/00—Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents
    • C02F5/08—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents
    • C02F5/10—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances
    • C02F5/12—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances containing nitrogen

Definitions

  • the invention relates to the use of polycarboxylic acid half-aitiides, which are obtainable by reacting polymers containing anhydride groups and compounds containing amino groups, as scale inhibitors.
  • scale inhibitors are used in industry. They are used in various technical fields, e.g. in boilers for steam generation, for the desalination of sea water by distillation, for the evaporation of sugar juice, for reverse osmosis and for oil and gas extraction or transportation.
  • inorganic salts which are difficult to dissolve such as e.g. Calcium carbonate, calcium sulfate, barium sulfate and strontium sulfate and form disturbing deposits inside the conveyor, which can even lead to production stoppages.
  • deposits are based on changes in the solubility parameters such as temperature and pressure during production or e.g. also mixing of formation water containing alkaline earth metal ions with sea water rich in sulfate ions in the formation or within the conveying devices. Deposits within the formation impair the permeability of the deposit and thus reduce the productivity of oil and gas.
  • the scale inhibitors used are, for example, polyacrylic acid, polymaleic acid or hydrolyzed water-soluble copolymers of maleic anhydride and, for example, C 2 -C 1 -efins.
  • the scale inhibitor dissolved in water can be injected into a press-in or production well or directly into the line.
  • Polycarboxylates or oligo- / polyphosphates are usually used here. If the scale deposits occur in the deposit in the inflow area of the probe, these can only be prevented by a squeeze treatment with a suitable scale inhibitor. In the case of a squeeze treatment, the dissolved scale inhibitor is introduced directly into the formation in excess, practically as a supply, in order to be deposited on the formation rock.
  • the inhibitor continuously separates from the formation rock during production.
  • the content of scale inhibitor in the water, which comes from the deposit together with oil, for example, is checked at certain intervals. Only with a sub If a critical concentration of scale inhibitor is exceeded, a new squeeze treatment is carried out.
  • reaction products of polymaleic anhydride and compounds containing amino groups is known.
  • Suitable reaction products are, for example, the adducts of iminodiacetate with polymaleic anhydride, and the addition products of diethanolamine or ethanolamine with polymaleic anhydride.
  • the effectiveness of such products in scale inhibition, however, is in need of improvement.
  • EP-B-0 009 171 discloses the preparation of polymaleic anhydride by polymerizing maleic anhydride in acetic anhydride with hydrogen peroxide as a catalyst.
  • the object of the present invention is to provide scale inhibitors which are more effective than those previously described.
  • the new scale inhibitors should also be biodegradable if possible.
  • polycarboxylic acid halamides which are obtained by reacting (a) Anhydride group-containing polymers having an average molecular weight M w of 200 to 100,000 and
  • Polymers containing anhydride groups and having an average molecular weight M w of from 200 to 100,000 are polymers of maleic anhydride, most of which are known from the prior art given above. They are particularly advantageous by polymerizing maleic acid anhydride. optionally in the presence of comonomers, in inert solvents in the presence of peroxyesters. Such processes are described for example in US-A-4 818 795, EP-A-0 264 627 and EP-B-0 276 464. The polymerization is usually carried out at from 60 to 200 ° C. in the presence of from 1 to 20% by weight, based on the monomers, of a peroxy ester.
  • the polymerization can be carried out, for example, in benzene, toluene, xylene, ethylbenzene, diethylbenzene, isopropylbenzene, diisopropylbenzene, tetraalkylbenzenes, naphthalene, methyl indole, dodecylbenzene and mixtures of the aromatic solvents mentioned. Radical polymerization of maleic anhydride is the preferred solvent
  • Suitable comonomers for carboxylic anhydrides for example, C 2 - to C ⁇ 2 -01efine, preferably C 2 - to C ⁇ and particularly preferably C 2 - to C 4 - ⁇ -olefins into consideration, for example ethylene, propylene, butene-1, isobutene, and Diisobutene.
  • These copolymers are mainly alternating polymers, ie they contain, for example, maleic anhydride and the comonomer in a molar ratio of 1: 1.
  • comonomers are styrene, Ci to C 4 alkyl vinyl ether, vinyl esters of saturated Ci to C 4 monocarboxylic acids, acrylic acid, methacrylic acid or mixtures of the comonomers mentioned.
  • alkyl vinyl ethers preference is given to methyl vinyl ether and ethyl vinyl ether.
  • Preferred vinyl esters are vinyl acetate and vinyl formate.
  • Copolymers of isobutene and maleic anhydride are preferably used as component (a). Such copolymers have, for example, an average molecular weight Mw of 200 to 100,000.
  • copolymers of maleic anhydride with 0.1 to 10% by weight, based on maleic anhydride, of at least one crosslinking agent containing two ethylenically unsaturated double bonds are, for example, glycol diacrylates and glycol dimethacrylates such as butanediol diacrylate or the diacrylates and dimethacrylates of polyalkylene glycols, for example of polyethylene glycol with molar masses from 100 to 10,000.
  • Other suitable crosslinkers are, for example, butanediol divinyl ether, pentaerythritol triallyaccharide and pentiallylsaccharose, triallyl. If they are present during the polymerization, the crosslinking agents are preferably used in an amount of 0.2 to 5% by weight, based on maleic anhydride.
  • the compounds preferably used as component (a) include polymaleic anhydrides which are obtainable by free-radical polymerization of maleic anhydride, if appropriate in the presence of comonomers copolymerizable therewith in toluene, xylene, ethylbenzene or mixtures thereof, and one of which is a medium ler molecular weight M w from 300 to 3,000.
  • Preferred copolymerizable comonomers are isobutene, diisobutene, ethylene and acrylic acid. If the polymerization of the maleic anhydride is carried out in an aromatic solvent, for example up to 50, preferably up to 40% by weight of the polymer can consist of chemically bound solvent in which the polymers have been prepared.
  • the content of comonomers in the copolymer is, for example, 10 to 90, preferably 30 to 70 mol%.
  • polymers containing anhydride groups are reacted with sarcosine (N-methylglycine), aminosulfonic acids, aminophosphonic acids or their alkali metal salts.
  • Aminosulfonic acids are understood to mean, for example, amino-Ci to C ⁇ -alkyl sulfonic acids, N-substituted aminoalkyl sulfonic acids and amino aryl sulfonic acids such as sulfanilic acid. From this group, preference is given to using taurine and N-alkyltaurines, the alkyl groups of which have 1 to 18 C atoms, e.g. N-methyl taurine.
  • Suitable compounds (b) are also aminophosphonic acids such as propylaminomethylenephosphonic acid or aminotrimethylenephosphonic acid.
  • Ethylbenzene or mixtures thereof are available and which have an average molecular weight M w of 300 to 3000 and
  • the reaction is preferably carried out in an aqueous medium.
  • an aqueous solution of an alkali metal salt, preferably a sodium or potassium salt, of at least one compound (b) is initially introduced and the polymeric compound (a) containing anhydride groups is added all at once, continuously or batchwise.
  • the reaction is carried out, for example, in the temperature range from 30 to 100, preferably 50 to 80 ° C.
  • the pH of the reaction solution is, for example, 6 to 12.
  • the reaction of compounds (a) and (b) takes from about 30 minutes to 5 hours, with higher reaction temperatures leading to shorter residence times.
  • the reaction can also be carried out at temperatures above 100 ° C., provided that the reaction is carried out under pressure in specially equipped apparatus.
  • the sodium salt of sarcosine and / or taurine is usually initially introduced as a 40 to 50% strength aqueous solution, the aqueous solution is heated to a temperature of 70 to 80 ° C. and the polymers containing anhydride groups are added in portions.
  • the reaction can also be carried out in tertiary amines such as tri-propylamine or pyridine as solvents. After the reaction has ended, the amine is distilled off and the reaction product is isolated in the form of the sodium salt.
  • the resulting Polycarbonsauregurami.de can be characterized using IR spectra and using the KOH titer.
  • the polycarboxylic acid halamides have, for example, molecular weights of 400 to 4500, preferably 500 to 2500.
  • the polycarboxylic acid halamides described above are used as scale inhibitors. They prevent the formation of crystals of hardness-forming salts, such as calcium carbonate, magnesium hydroxide, magnesium carbonate, calcium, barium or strontium sulfate, calcium phosphate (apatite) in water-carrying systems, or they influence the formation of precipitates of such salts in such a way that no hard or rock-hard deposits are formed, but separations which are easily washed out in water are formed. In this way, the surfaces of, for example, heat exchangers, pipes or pump components are kept free of deposits.
  • the scale inhibitors are usually used in substoichiometric amounts, e.g. in amounts of 0.1 to 100, preferably 0.5 to 25 ppm, based on the respective amount of water.
  • the water-carrying systems are e.g. around open or closed cooling circuits, for example of power plants or chemical plants, such as reactors, distillation apparatuses and similar components, in which heat has to be dissipated.
  • Scale inhibitors can also be used in boiler water and steam generators, preferably in the range of water temperatures below 150 ° C.
  • a preferred application of the scale inhibitors to be used according to the invention is the desalination of sea and brackish water by distillation or membrane processes, such as, for example, reverse osmosis or electrodialysis.
  • Another application of the deposit inhibitor is e.g. given the evaporation of sugar juices from cane or beet sugar.
  • Another important application is the use of polycarboxylic acid halamides as scale inhibitors in the oil
  • US-A-4 818 795 made by polymerizing maleic anhydride in xylene. 0.7 mol of sarcosine Na salt was used per mole of anhydride groups in the polymer.
  • reaction mixture 35 27 parts of water, the reaction mixture is adjusted to a solids content of 50%.
  • the molar ratio of anhydride units in the copolymer to sodium sarcosinate was 1: 0.3.
  • Isobutene and maleic anhydride are added to a solution heated to 70 ° C. to 51.5 parts of a 50% strength aqueous solution of taurine sodium salt and stirred at 80 ° C. for 3 hours. By adding water, a solids concentration of 50% is
  • Adduct 7 The procedure is as described for the preparation of adduct 5, but using 34.3 parts of the alternating copolymer of isobutene and maleic anhydride and 73.5 parts of 50% aqueous tanrin-sodium salt solution. This gives 342 parts of a SO% icren aqueous solution of the adduct, in which the molar ratio of the anhydride groups to taurine is 1: 1.
  • adducts 1-7 are investigated as inhibitors in the formation of calcium and magnesium hydroxides and carbonates from synthetic seawater solutions.
  • seawater desalination calcium carbonate and magnesium hydroxide in particular form firmly adhering and disruptive deposits on the heat exchanger surfaces.
  • the formation of calcium sulfate is also a serious problem.
  • the test solution consists of an aqueous saline solution
  • the synthetic sea water solution is then ppm with 25 of staggered and in Examples 1 to 7 used adducts 1-7 pumped for 3 hours' in a dynamic circulation apparatus in a circle. After a test period of 3 hours, samples are taken which are titrimetrically analyzed for the water hardness content. Due to the decrease in water hardness in the course of the experiment, one can count back to the deposits which form in the heat exchanger. The lower the degree of hardness in the water sample taken, the more coating has deposited on the heat exchanger tubes. The water hardness values determined are listed in Table 1. A high degree of hardness after a test time of 3 hours suggests good scale inhibition (deposit prevention).
  • test results of the adducts 1 to 7 to be used according to the invention in comparison to a market product are given in Table 1.
  • the market product is a polymaleic acid with a molecular weight of 1000.
  • Test conditions Temperature from the test water outlet: 112 ° C
  • compositions of synthetic waters are Compositions of synthetic waters:
  • the evaluation scale ranges from "+++” to "-", where +++ stands for very good, i.e. no deposits and

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Environmental & Geological Engineering (AREA)
  • Engineering & Computer Science (AREA)
  • Hydrology & Water Resources (AREA)
  • Water Supply & Treatment (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Abstract

Utilisation, comme agents antitartre, de semi-amides d'acides carboxyliques obtenus par réaction (a) de polymères renfermant des groupes anhydrides, de masse moléculaire moyenne Mw comprise entre 200 et 100.000 et (b) de sarcosine, d'acides aminosulfoniques, d'acides aminophosphoniques ou de leurs sels de métaux alcalins.
PCT/EP1996/004561 1995-10-27 1996-10-21 Utilisation de semi-amides d'acides polycarboxyliques comme agents antitartre Ceased WO1997016464A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE1995140090 DE19540090A1 (de) 1995-10-27 1995-10-27 Verwendung von Polycarbonsäurehalbamiden als Scale-Inhibitor
DE19540090.9 1995-10-27
DE19548318.9 1995-12-22
DE1995148318 DE19548318A1 (de) 1995-12-22 1995-12-22 Verwendung von Polycarbonsäurehalbamiden als Scale-Inhibitor

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WO1997016464A1 true WO1997016464A1 (fr) 1997-05-09

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005343845A (ja) * 2004-06-04 2005-12-15 Hakuto Co Ltd アクリロニトリルの重合抑制剤および重合抑制方法
JP2006273746A (ja) * 2005-03-29 2006-10-12 Hakuto Co Ltd アクリロニトリルの重合抑制剤および重合抑制方法
WO2008077829A1 (fr) * 2006-12-21 2008-07-03 Basf Se Procédé et polymère pour éviter la formation de tartre à base de ba/sr avec fonctionnalité de phosphore détectable
CN114031717A (zh) * 2021-10-19 2022-02-11 东莞市长洲化工科技有限公司 高磺酸基含量的聚羧酸盐及其制法和在制备分散剂中的应用
US11502323B1 (en) 2022-05-09 2022-11-15 Rahul S Nana Reverse electrodialysis cell and methods of use thereof
US11502322B1 (en) 2022-05-09 2022-11-15 Rahul S Nana Reverse electrodialysis cell with heat pump
US11855324B1 (en) 2022-11-15 2023-12-26 Rahul S. Nana Reverse electrodialysis or pressure-retarded osmosis cell with heat pump
US12040517B2 (en) 2022-11-15 2024-07-16 Rahul S. Nana Reverse electrodialysis or pressure-retarded osmosis cell and methods of use thereof
US12341228B2 (en) 2022-11-15 2025-06-24 Rahul S. Nana Reverse electrodialysis or pressure-retarded osmosis cell and methods of use thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6024384A (ja) * 1983-07-20 1985-02-07 Harima Kasei Kogyo Kk 硬水に安定な腐食防止剤
JPS6079020A (ja) * 1983-10-06 1985-05-04 Nippon Zeon Co Ltd 新規な水溶性共重合体
JPS6079012A (ja) * 1983-10-06 1985-05-04 Nippon Zeon Co Ltd 水溶性ジカルボン酸イミド系化合物の製造法
EP0261589A2 (fr) * 1986-09-19 1988-03-30 BASF Aktiengesellschaft Procédé de préparation d'acide polymaléique
US4801388A (en) * 1986-03-21 1989-01-31 Nalco Chemical Company Modified acrylamide polymers used as scale inhibitors

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6024384A (ja) * 1983-07-20 1985-02-07 Harima Kasei Kogyo Kk 硬水に安定な腐食防止剤
JPS6079020A (ja) * 1983-10-06 1985-05-04 Nippon Zeon Co Ltd 新規な水溶性共重合体
JPS6079012A (ja) * 1983-10-06 1985-05-04 Nippon Zeon Co Ltd 水溶性ジカルボン酸イミド系化合物の製造法
US4801388A (en) * 1986-03-21 1989-01-31 Nalco Chemical Company Modified acrylamide polymers used as scale inhibitors
EP0261589A2 (fr) * 1986-09-19 1988-03-30 BASF Aktiengesellschaft Procédé de préparation d'acide polymaléique
US4818795A (en) * 1986-09-19 1989-04-04 Basf Aktiengesellschaft Polymaleic acid, its preparation and its use

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005343845A (ja) * 2004-06-04 2005-12-15 Hakuto Co Ltd アクリロニトリルの重合抑制剤および重合抑制方法
JP2006273746A (ja) * 2005-03-29 2006-10-12 Hakuto Co Ltd アクリロニトリルの重合抑制剤および重合抑制方法
WO2008077829A1 (fr) * 2006-12-21 2008-07-03 Basf Se Procédé et polymère pour éviter la formation de tartre à base de ba/sr avec fonctionnalité de phosphore détectable
US20100171070A1 (en) * 2006-12-21 2010-07-08 Basf Se Patents, Trademarks And Licenses PROCESS AND POLYMER FOR PREVENTING Ba/Sr SCALE WITH A DETECTABLE PHOSPHORUS FUNCTIONALITY
CN114031717A (zh) * 2021-10-19 2022-02-11 东莞市长洲化工科技有限公司 高磺酸基含量的聚羧酸盐及其制法和在制备分散剂中的应用
US11502322B1 (en) 2022-05-09 2022-11-15 Rahul S Nana Reverse electrodialysis cell with heat pump
US11502323B1 (en) 2022-05-09 2022-11-15 Rahul S Nana Reverse electrodialysis cell and methods of use thereof
US11563229B1 (en) 2022-05-09 2023-01-24 Rahul S Nana Reverse electrodialysis cell with heat pump
US11611099B1 (en) 2022-05-09 2023-03-21 Rahul S Nana Reverse electrodialysis cell and methods of use thereof
US11699803B1 (en) 2022-05-09 2023-07-11 Rahul S Nana Reverse electrodialysis cell with heat pump
US12107308B2 (en) 2022-05-09 2024-10-01 Rahul S Nana Reverse electrodialysis cell and methods of use thereof
US11855324B1 (en) 2022-11-15 2023-12-26 Rahul S. Nana Reverse electrodialysis or pressure-retarded osmosis cell with heat pump
US12040517B2 (en) 2022-11-15 2024-07-16 Rahul S. Nana Reverse electrodialysis or pressure-retarded osmosis cell and methods of use thereof
US12341228B2 (en) 2022-11-15 2025-06-24 Rahul S. Nana Reverse electrodialysis or pressure-retarded osmosis cell and methods of use thereof
US12374711B2 (en) 2022-11-15 2025-07-29 Rahul S. Nana Reverse electrodialysis or pressure-retarded osmosis cell with heat pump

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