MXPA97003623A - Compositions for the treatment of ag - Google Patents

Abstract

The reaction of a water soluble phosphite salt with a salt of water soluble fumarates in an aqueous solution and in the presence of a free radical initiator provides a synergistic mixture of a phosphoenosuccinate having from 0.1 to 5% by weight of a salt of 1-phosphene-1,2,3,4-tetracarboxybutane, whose mixture is superior to the conventional phosphonosuccinates prepared and the reaction products maleate / phosphite as an inhibitor of corrosion and scale for aqueous systems and as a deflocculant and a kidnap

Description

"COMPOSITIONS FOR WATER TREATMENT" The present invention relates to compositions suitable for use in the treatment of water co or corrosion and scale inhibitors. The compositions are also useful as loculants, sequestrants and cement curing retardants, and can be used to provide anticorrosive pigments for use in paints. Phosphonosuccinic acid, H 2 O 3 PCHCOOHCH 2 COOH and its salts have been obtained by reacting an alkyl phosphite ester with an alkyl maleate in the presence of a base catalyst in an anhydrous medium, and saponifying the resulting phosphorosuccinate ester. This is known as capable of reducing scale, when present in low concentrations (for example 20 to 100 ppm), in water systems that form scale and in the reduction of corrosion of ferrous metals in water systems that contain calcium and are corrosive. However, it is expensive to achieve these results through the aforementioned route and it is also less effective than other cheaper agents. British Patent No. 1458235 proposes making a phosphonated oligomer of acrylic acid by reacting phosphorous acid with acrylic acid in water and in the presence of a persulfate free radical source. However, it has been found that under the conditions described, the product is predominantly polyacrylate. The phosphorous NUR confirms that only traces of phosphonate are formed. European Patent No. 0491391 describes a reaction of sodium phosphite with active olefins such as sodium maleate in an alkaline solution in the presence of a peroxide or persalt. The reaction forms a predominantly consistent mixture of phosphorus succinate and l-phosphono-1,3,3,4-tetracarboxybutane (the phosphonated dimer of succinic acid hereinafter referred to as "the dimer") together with sodium phosphate and traces of higher oligomers of succimic acid. The product is vastly superior to conventional phosphonosuccinic acid as a corrosion inhibitor. European Patent No. 0569731 shows that the dimer is a corrosion inhibitor significantly more effective than the phosphonosuccinic acid, but that the mixture of the two is synergistic. The mixture obtained in the above reaction typically has an average degree of polymerization of about 1.2 to 1.3 corresponding to about 15 to 202 by weight of the dimer. This corresponds fortuitously to the optimum synergistic effect such as shows in Example 6 of European Patent No. 0569731. Both European Patent No. 0491391 and No. 0569731 describe the reaction of phosphite salts with olefin in general form, but do not recommend the use of fumaric acid or its salts . European patent No. 0491391 states that comparatively non-reactive fumaric acid and patent No. 0569731 states that the fumarate does not react to a significant degree under normal reaction conditions. We have found that when a fumarate salt is reacted with a phosphite salt in an aqueous alkaline medium containing free radical initiator, a product consisting predominantly of phosphonosuccinate is formed, together with only one race of dimer (between of 0.5 and about 2% by weight of the total solids). Because the reaction is comparatively slower, the competent reaction to form phosphate can give rise to high levels of the latter, which has been found to affect the stability of the product. We have discovered that the problem can be solved by using a relatively dilute starter solution and / or by adding the initiator sufficiently slowly to the mixture. Surprisingly, the foefonosuccinate obtained from fumarate phosphonation was found to be superior to the product previously described in European patents No. 0419391 and No. 0569731, obtained by the phosphonation of maleate salts, when both were compared in their use as an inhibitor of corrosion and scale in alkaline water systems. Such systems have presented problems that until now conventional water treatment agents have proved inadequate to solve them. These discoveries are directly contrary to the clear knowledge with which the aforementioned prior art counts. The product is a particularly effective inhibitor for incrustations in hard waters (for example above 200 ppm of calcium) and with high pH values, for example above 8. It has also been found to be a corrosion inhibitor. substantial superior entity compared to the phosphonosuccinic acid prepared by the most expensive route using ester, in a wide range of conditions but especially in relatively high concentrations of calcium and pH. The product has been found to be effective as a deflocculant for deflocculating suspensions of fine solids, such as titanium oxide, and as a sequestering tool, for example for the addition to detergent formulations. Our invention thus provides a method for obtaining a water treatment agent which comprises reacting a water soluble phosphite salt with a fumarate salt in water in the presence of a free radical initiator. According to a second embodiment, the inhibitor is added to a synergistic mixture of phosphite and the fumarate in a range and for a time sufficient to form a phosphono succinate resultant greater than 80% based on the weight of the phosphite used but not sufficiently fast way to form more than 8% by weight of phosphate based on the weight of the phosphite used. According to a third embodiment, the invention provides a mixture of a phosphono succinate salt having from 0.1 to 5% by weight based on the total weight of the mixture of a salt of 1-phosphon-1, 2.3, 4-tetracarboxybutane. According to a fourth embodiment, this mixture contains less than 8% by weight of phosphate based on the total weight of the mixture. According to a fifth embodiment, the invention provides the use in the treatment of water or as a retardant deflocculant of cement curing or sequestering a composition prepared according to said first or second embodiments and / or comprising a mixture in accordance with said third or fourth embodiments. The method of our invention according to the first embodiment requires the use of a salt at least sparingly soluble in water of fumaric acid such as an alkali metal or an ammonium salt. In general, the potassium and sodium salts are preferred. Similarly, the phosphite is preferably a water-soluble salt of for example an alkali or ammonium metal, preferably solid or potassium. The reagents are preferably used in substantially stoichiometric proportions. Small excesses of any reagent can be tolerated, but result in a reduction in efficiency with respect to the excess agent. For commercial reasons we prefer that none of the reagents be present in a stoichiometric excess of more than about 10%, although it is recognized that somewhat larger excesses are technically possible. The inhibitor is preferably a hydrogen peroxide, although other free radical sources can also be used such as hydroperoxides, chlorine dioxide, sodium or other alkali metal persulfates, percarbonates, chlorates or hypochlorites, and / or compounds such as acid. 4,4 * -azobisolvaleric, electrolysis, ultraviolet radiation or other ionizing radiation or ultrasound. The inhibitor is preferably supplied to the reaction medium in a sufficient rate to maintain the reaction at least until a significant amount of the product has been obtained. In general, for the economic operation, the result must be greater than 50% preferably greater than 70%, more preferably greater than 80%, for example greater than 90% and the reaction must take place during 30 hours, preferably less than 25 hours, for example from 9 to 20 hours. In reaction media, an aqueous medium preferably containing more than 30%, more preferably more than 50%, especially more than 60%, for example 60 to 70%, by weight of the reactants. Concentrations above 70% in solids have a generally undesired viscosity. A preferred range is between 63 to 68% solids. The inhibitor is preferably added to the reaction medium continuously or intermittently and at a rate sufficient to maintain the reaction until it is substantially complete. The rate of addition of the inhibitor is controlled so that it is sufficiently a + a to avoid a slow reaction not economic, but not so high as to cause a substantial contamination of the product by the formation of phosphate. To avoid the latter we prefer to use as the initiator a relatively dilute hydrogen peroxide solution having an intensity of less than 10% by volume in volume, ie from 0.5 to 5%, more preferably from 1 to 4%, and especially from 2 to 3%. The use of a dilute initiator solution allows the rate of aggregation of the peroxide to be more easily controlled. The diluted peroxide is typically added at a rate of 2 to 10 cm3 hour-1 mol-1 based on the furnarate, preferably 5 to 8, for example 6 to 7, during a period ranging from 5 to 40 hours. However to minimize phosphate formation it is preferred to reduce the rate of peroxide addition after the reaction is complete by about 70%, usually less than 8 to 10 hours, in a value from 1 to 5 cm3 hours-1 mol-1 , for example from 2 to 4. The reaction can then be continued for 5 to 10 more hours, for example until the yields greater than 90% have been achieved. The optimum dose range will depend on the initiator used at the concentration to which the reagent concentration is added, and the pH and temperature of the reaction mixture. The previously recommended rates and ranges are applied to the diluted peroxide that is added to a reaction mixture containing 75% solid of a reflux under atmospheric pressure with a pHlO. The reaction is desirably carried out at an elevated temperature and preferably at a reflux temperature. The reflux can be adjusted to maintain the preferred water concentration of the sludge. We prefer that the reaction be carried out in an inert atmosphere, for example under a blanket of nitrogen. It is possible to carry out the reaction at temperatures which are above the normal boiling point of the mixture in an autoclave, for example temperatures up to 250 ° C. The pH of the reaction mixture is preferably alkaline. Although it is technically possible to use a pH as low as 6, or even 5.5, the reaction is very slow at any pH below 7 and requires a pH above 7.5 to get it to be completed in more than 90 % in a real time. The preferred pH is from 8 to 12, typically from 9 to 11. A higher pH generally gives a more rapid reaction but a pH above 10.5 can result in an undesirably alkaline product for many purposes. The termination of the reaction can be monitored by means of a 3ip N? R in 2O. In this way the range of phosphonate and phosphate formation can be checked and the speed of vision of the initiator can be adjusted where necessary to achieve the reaction conditions. We prefer to include an amount from about 1 to 10% by weight of the total mixture of the product from a previous batch. The above-described description specifically applies to batch preparations but can be easily adapted for a continuous or iconic operation which includes the preparation in a pipe or sealed reactor. It is also possible to use reactors of said fluid. The mixture according to the third and fourth embodiments of the invention comprises phosphonosuccinic acid or its salts and from 0, 1 to 5% of the weight of total solids, preferably from 0.2 to 4%, especially from 0.5 to 2% of phosphono-1, 2,3, 4-tetracarbox? butane (the dimer). The salt may preferably be a water soluble salt such as an alkali metal (eg, sodium or potassium) or an ammonium salt. Alternatively, this may be a calcium salt or other transition metal or alkaline earth metal, for example barium, barium or magnesium salt without aluminum, iron, copper, nickel or cobalt. The water-soluble salts are useful for the treatment of water and the water-insoluble salts are valuable as anticorrosive pigments, for example for incorporation into paints and coating compositions. The mixture preferably contains less than 8% phosphate, expressed as disodium phosphate, the weight based on the total solids, more preferably less than 7% by weight, especially less than 7.5% by weight. Typically, the phosphate is present in proportions that are between 4 and 6%. In general, we prefer that less than 3.5 mol% of the phosphorus in the mixture be present as phosphate and especially less than 3 mol%, for example 0.5 to 2.5 mol%. According to the fourth embodiment, our invention provides a method for treating water, particularly water containing more than 25 ppm of calcium and / or barium, especially more than 50 ppm, for example more than 100 ppm, more especially more than 200 ppm. , and / or a pH greater than 7.5, especially a pH greater than 8. For example, the compounds and mixtures of the invention can be used in the pressure treatment of oil wells in conjunction with calcium salts, or they can be added to the drilling muds in the well injection water, in the water produced or in the water for hydrostatic testing, as well as to various other industrial applications of cooling water and process water, and to water to be used in water treatment systems. central heating. They can be used to inhibit barium sulfate incrustations. In drilling well treatment, for example to prevent the formation of BaSO fouling «when seawater is injected into the crude strata containing high levels of barium typically impregnates the formation of well environments with an inhibitor calcium salt which is subsequently washed in an aqueous system circulating in the well to provide a slow controlled release. For example, in the oil wells the orifice is washed with an aqueous surfactant to provide a surface for the flow of the water and then the orifice is impregnated with an inhibitor solution. The calcium salt is formed in situ either by calcium in the formation, where the latter comprises limestone, or by the subsequent treatment of the well with an aqueous calcium salt, for example where the formation comprises sand. Alternatively, the compositions can be used, for example, to treat boiling water, water used in evaporative cooling systems, water in heat exchange systems including cooling water and water in central heating systems, process water used in chemical, metallurgical operations and other manufacturing operations, injection in oil wells and produced water, water used in hydrostatic tests and water for swimming pools and for air conditioning. The compound and mixtures are particularly useful in the treatment of chlorinated water systems for which many agents are ineffective. Effective concentrations may typically be within the range of 0.1 to 300 ppm depending on the nature of the aqueous system but are usually less than 100 ppm and generally less than 50 ppm, preferably from 0.5 to 20 ppm, especially from 1 to 10. ppm, for example from 1.5 to 4 ppm. The compositions are effective in inhibiting corrosion of ferrous metals including rolled steel and also of aluminum and its alloys. These can inhibit the formation of calcium carbonate or calcium sulfate in scale. As well as barium and strontium inlays. According to a further embodiment, the invention provides a corrosion inhibiting pigment which is a solid composition which can be prepared by reacting an aqueous concentrated solution of water-soluble corrosion inhibitor according to the invention with a base or salt of calcium, zinc, barium, aluminum or another polyvalent metal and precipitating a solid salt of a polyvalent metal. According to a further embodiment, the invention provides a coating composition which inhibits corrosion and which contains a pigment according to the invention. The corrosion inhibiting pigment may be dissolved or dispersed in an anti-corrosive paint, varnish, enamel, lacquer or other coating formulation. The formulation may comprise a volatile liquid carrier, such as water or a volatile organic solvent that includes a petroleum base, turpentine, ketones, esters and / or aromatic hydrocarbon solvents, and / or a drying oil, such as flaxseed oil. , soybean oil, tung oil and dehydrated castor oil, which may optionally be dissolved in said volatile organic solvent or emulsified in said water. The formulation may also typically comprise a resin, for example a polyester resin, for urea aldehyde, melamine acrylic, polyurethane, vinyl chloride, vinyl acetate, or pheno or epoxy resin dissolved or dispersed therein and / or a pigment scattered. We prefer that the pigment be or comprise other corrosion inhibiting pigments such as red lead, zinc potassium chromate, metallic zinc or aluminum or zinc oxide powder and / or that the formulation should contain one or more of the other inhibitors of the invention. corrosion indicated above in addition to the corrosion inhibiting pigment of the invention. The coating compositions may also contain any of the conventional paint ingredients, including pigments such as titanium oxide, iron oxide, carbon black, phthalocyanine pigments or aluminum stearate, chlorinated rubber, polystyrene, silicones, asphalt, wetting agents, dispersants, emulsifiers, biocides, flocculants, marine anti-flocculants, anti-foam, viscosity agents, flame retardants, fluorescent agents, aerosol propellants, talc, clay and / or plasticizers. Alternatively, the water-soluble corrosion inhibitors of the invention can be used to provide a corrosion inhibiting treatment for metal surfaces such as steel, aluminum and aluminum alloys after any machining and before their storage, coating, electroplating, polishing or Recorded. Typically, the part should be coated with an aqueous solution containing at least an operative amount of said corrosion inhibitor, for example from 10 to 500 ppm, preferably from 25 to 300, for example from 20 to 200, especially from 25 to 100, and more especially 30 to 80 ppm. After coming into contact with the corrosion inhibiting solution, the part can be washed and / or subjected to one or more finishing or coating operations for example by means of a resin coating, a lacquering, enamelling, painting, electrophoretic coating, coverage by spraying, vapor deposition, electrodeposition, chemical etching or electric polishing, or simply can be arranged for storage. The piece can be greased for storage, but an advantage of the treatment is that greasing and subsequent degreasing can be avoided. The composition of the invention can be used to defloculate dispersed or suspended solids in a liquid medium. The dispersed or suspended solid can be any solid particle that is chemically inert enough to be dispersed or suspended in the aqueous medium. The particles are preferably inorganic, and substantially insoluble in water, for example a mineral such as an aluminosilicate or a metallic mineral. Examples these include talc, calcite, barite, mica, such clay ran china clay and bentonite, shales, hematite, bauxite, magnetite, galena, copper or iron pyrites, coal, zeolite, titanium oxide and zinc oxide. The invention also covers the suspension of soluble or sparingly soluble solids in saturated aqueous solutions thereof. The solid can, for example, be a detergent former or a fabric conditioner, a clay to be used in the manufacture of ceramic articles? or an abrasive pigment, a dye, a pesticide, a cosmetic or a pharmaceutical product, or a weight-increasing agent for sludge or drilling of oil wells. The dispersed particles may alternatively comprise a polymer, resin or laxative, for example for use in paints and printing inks. The particle size of the solid is preferably small enough to allow the particle to disperse or suspend rapidly. For example, we prefer that the particle size be less than 1 mm, for example less than 0.5 mm, preferably 0.5 to 100 microns, especially 1 to 50 microns. The proportions of solid can be from 1 to 90% by weight based on the total weight of the composition. More usually the composition comprises from 10 to 90%, preferably from 20 to 70%, for example 30 to 65% by weight suspended solids. The liquid medium may be water optionally containing a dispersant such as a dilute surfactant or a lignin sulfonate, and / or suspending agents such as carboxymethyl cellulose or polyvinyl pyrrolidone. The composition can, for example, have the form of a mechanical dispersion, mud, paste, clay or thick liquid, or a settled dispersion capable of redispersing by shaking or stirring. The pH of the liquid medium is usually neutral or alkaline, for example greater than 7, preferably from 8 to 14, especially from 9 to 1.2. The liquid medium may optionally contain organic solvents emulsifiable or iscible in water, but when they are not normally necessary and unless specifically required, for example when the suspension is to be used as a paint composition, they are preferably absent. . The invention is of particular value in the provision of highly mobile concentrated pigment slurries, and especially titanium oxide, for use as for example in paints and other coating compositions. According to the specific embodiment there is provided a coating composition comprising: a liquid vehicle of aqueous base, an organic binder comprising a drying oil or resin emulsified or dispersed with said liquid carrier; particles or a pigment, which in the absence of a deflocculant, have the tendency to flocculate and are suspended or dispersed in said liquid carrier, and the water-soluble composition of the invention in an amount sufficient to inhibit flocculation of the pigment. The preferred pigment is titanium oxide but any other pigment having the tendency to flocculate can also be used. Other useful pigments include iron oxide, carbon black, phthalocyanine pigments or aluminum stearate. The pigment may comprise corrosion inhibiting pigments such as red lead, potassium zinc chromate, metallic zinc or aluminum powder or zinc oxide or aluminum or calcium zinc phosphate, or citrates. The composition can be added to cement compositions that include portland cement, hydraulic lime, putzolana, slag, bauxite, cementitious mix, dental cement, plaster, plaster, concrete, cement slurry and fillers to prevent premature curing. The compositions are useful as sequestrants, to be used as forming agents, oxide replenishers and peroxide stabilizers in detergents and bleaching preparations. The composition may be present typically in the detergent in concentrations ranging from 0.01 to 20%, usually from 0.1 to 10%, for example from 0.5 to 5% based on the weight of the formulation. The detergent may contain from 2 to 50% by weight of surfactants, including any of the surfactants listed below, preferably from 4 to 40%, especially from 5 to 30%, for example from 8 to 20%. The detergent preferably contains from 5 to 50% by weight of formers such as sodium tripolyphosphate, eodium pyrophosphate, zeolite or sodium citrate, and an optical brightener and soil suspending agent in smaller amounts, for example from 0.01 to 2% each. The products according to the invention can be used in combination with other water treatment agents that include surfactants, such as anionic surfactants (for example C 0 or -20 alkylbenzene sulfonates, C 10-20 alkylsulfates, C 10-20 alkyl, to 25 mol ether sulphates, CIQ-20 paraffin sulfonates, C10-20 soaps, C10-20 alkyl phenol sulphates, sulfosuccinates, sulfosuccina ates, lignin sulphonates, fatty ester sulphonates, C10-20 alkyl phenyl ether sulphates, C10-20 alkyl ethanola ida sulphates, C10-20 salts of alpha sulfo fatty acid, C10-20 acyl sarcosinates, isethionates, C10-20 acyl taurides, C10-20 alkyl hydrogen phosphates), nonionic surfactants (eg ethoxylated C10-20 alcohols and / or propoxylates, ethoxylated and / or propoxylated carboxylic acids Cj.0-20, alconolanides, amino oxides, and / or C10-20 acyl sorbitan and / or glyceryl ethoxylates). Amphoteric surfactants (for example betaines, sulfobetaines, and / or quaternized imidazolines) ) I cationic surfactants (for example benzalkonium salts, C10-20 alkyl trirnethyl ammonium salts, and / or C10-20 alkyl trimethyl or tris (hydroxymethyl) salts of phosphonium); sequestrants, chelating agents, corrosion inhibitors and / or other critical agents (for example sodium tripolyphosphate, sodium tetracycium ethylenediamine, sodium triacetate nitrile, potassium tetrapyrrophosphate, aceto diphosphonic acid and its salts, trismethylene phosphonic acid ammonium and its salts , ethylenediamine tetrakis (methylene phosphonic acid) and its salts); tolitriazole and mixtures of nitrate, benzoate, 2-hydroxy-2-phenehoacetic acid and its salts and / or 2-phosphono-l, 2,4-tricarboxy butane and its salts) biocides (for example tetrakis (hydroxyethyl) phosphonium salts , formaldehyde, glutaldehyde); oxidizing biocides and / or bleaches (for example chlorine, chlorine dioxide, p> hydrogen peroxide, sodium perborate); foam controlling agents such as silicone defoamers, oxygen scavengers such as hydrazines and / or hydroxylannins; buffering agents and / or pH controllers; such as amines, borates, citrates and / or acetates; chromium salts, zinc salts; and other water treatment agents such as polymeric dispersants and coagulants including polymaleic, polyacrylic and polyvinyl sulfonic acids and their salts, starches and / or carboxymethyl cellulose and / or olibdates. The invention provides formulations comprising an effective amount of a mixture or product of the invention as described above and any of the aforesaid known water treatment agents.

Such formulations may contain, for example, from 5 to 95% by weight of a product of the invention and from 5 to 90% by weight of one or more of any of the above-mentioned water treatment agents. Additionally, the formulations may contain up to 90% of a diluent, filler or solvent. The invention, according to a further embodiment, provides aqueous solutions containing from 0.5 ppm for the saturation of any of the aforementioned mixtures of products or formulations according to the invention. The invention is illustrated by means of the following examples: EXAMPLE 1 A solution of phosphorous acid (4.0 moles, 328.0 g) and fumaric acid (4.0 moles, 464.3 g) in water (800 rolls) was stirred rapidly to form a 50% uniform paste in water. Sodium hydroxide that was added during one hour (16 moles eq: 1280 g). The solution (adjusted to pH 10) was reduced to a 65% sludge by distillation of water using a Dean Stark apparatus (1172 g) and heated under reflux for 30 minutes. A solution of 25% by volume hydrogen peroxide was added under a nitrogen atmosphere to the refluxing reagents in an initial range of 25 cm3 hr-i with co-distillation of water to maintain a 65% sludge. After eight to nine hours the speed was reduced to 10 cm3 hr-i. Continuing with an additional addition of 10 hours of refluxing peroxide (total addition in 19 hs time), 600 25 cm3 of water was added to the reaction mixture and heated under reflux for 30 minutes, cooled to 10 ° C and it was filtered through a grade 3 filter to remove residual insoluble disodium fumarate. 3iPNf1R (in D2O) indicated 95% conversion to the tetrasodium salt of phosphonosuccinic acid. A solution at 52% by weight of the product was separated by ion chromatography and comprised 45.4% by weight of phosphonosuccinic acid, 0.72% of dimer, 2.3% of phosphate, 0.2% of phosphite and 0.4 % maleate.

EXAMPLE 2 The following was charged to a reaction vessel: 1 liter of water, 57.1 g of the product of Example 1 (40% solution), fumaric acid (464.0 g, 4 moles), phosphorous acid (327.0 g., 3.99 moles). This was then neutralized with 1226.7 g. of sodium hydroxide (50%), and the pH was adjusted to 10.1. 335 mi. of water were then removed by distribution to give a slurry containing 65% solids. 600 mi. of a 2.4% hydrogen peroxide solution were then added for 25 hours with water removed from the vessel by distillation at the same rate as its aggregate. This gave a 95% conversion of phosphono succinate. The product had a crystal size of 10 to 20 microns and low density.

EXAMPLE 3 An amount of 1849 g of the product of Example 1 (405 of solution)? fumaric acid (300 g, 2.58 mol) and phosphorous acid (212 g, 2.58 mol) were charged to a reaction vessel. These are neutralized and the pH is adjusted to 10.1 with 827.1 g of a sodium hydroxide solution (50%). 913 g of water were then removed by distillation to give a sludge containing 65% solids. 600 ml of a 2.5% hydrogen peroxide solution were then added for 25 hours. The product had an average crystal size less than 5 microns and was very viscous.

EXAMPLE 4 The product of Example 1 was compared to phosphono succinate obtained by the saponification of the methyl ester resulting from the reaction of methyl phosphate with methyl maleate. The comparison was made using test samples that included immersing weighing samples of steel rolled in water containing varying concentrations of calcium in a pH range. The weight loss was measured and the corrosion was calculated in thousandths per year. The results are shown in the following Table.

PICTURE EXAMPLE 5 The product of Example 1 was compared, in a tube blocking experiment, with the product of sodium oleate phosphonation as described in European Patent No. 056973. Water at 60 ° C containing 600 ppm of calcium expressed as carbonate equivalent and 450 ppm HCO3 expressed as equivalent calcium carbonate (Langelier 2 index, 6) and with a pH at 20 ° C of 9, was pumped through a stainless steel capillary for 3,500 seconds and the differential pressure was measured. The start of incrustations was recorded as an increase in pressure that resulted exponential with tube blockage. With 0.5 pprn of the comparative example, the blockage occurred after 2,500 seconds. With the same concentration of Example 1, only a partial block was observed even after 3,500 seconds. With 1 ppm of inhibitor both products were effective in preventing blockade through the EXAMPLE 6 The deflocculating capacity of the Example product was compared with that of a phosphite / maleate reaction product according to the example of European document no. 0569731 which had a degree of polymerization of 1.3. The two products were each added to samples of 65% by weight of a suspension of titanium oxide in water at a level of 0.1% by weight of the mixture. The viscosities of the two mixtures were measured at 25 ° and 21 seconds-1 using a controlled tension rheometer, rCarrimed "with parallel plates of 4 cm and a gap of 1 mm.The furnarate product of Example 1 lowered the viscosity from 10, 88 Pas at 0.153 Pas The maleate product of the prior art only decreased the viscosity to 0.336 Pas.

Claims (6)

NOVELTY OF THE INVENTION CLAIMS

1. A method for making a water treatment agent comprising reacting a water soluble phosphite salt with water with a water-soluble fumarate salt in the presence of a free radical initiator in water. A method according to claim 1, wherein the initiator is added to the mixture of phosphite and fumarate at a range, and for a time, sufficient to form a phosphono succinate product greater than 80% based on the weight of the phosphite employee, but not fast enough to form more than 8% phosphate. 3. A method according to claim 2, wherein the free radical initiator is hydrogen peroxide. 4. A mixture of a phosphonosuccinate salt with a l-phosphono-l, 2,3,4-tetracarboxybutane salt in an amount ranging from 0.1 to 5% by weight based on the total weight of the mixture. 5. A mixture according to claim 4 containing less than 8% by weight of phosphate. 6. A method for treating waters, for inhibiting metal corrosion and / or scale deposition comprising adding to them from 0.1 to 300 ppm of a mixture according to any of claims 4 and 5. 8. A detergent formulation comprising from 0.01 to 20% by weight of a mixture according to any of claims 4 and 5. 9. A suspension of particles of a flocculable solid in water containing a flocculation inhibiting amount of a mixture according to any of claims 4 and 5.