Classifications

• • 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
• • 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
• • 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
  • C02F5/14—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 phosphorus
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
  • C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
  • C07F9/02—Phosphorus compounds
  • C07F9/28—Phosphorus compounds with one or more P—C bonds
  • C07F9/38—Phosphonic acids [RP(=O)(OH)2]; Thiophosphonic acids ; [RP(=X1)(X2H)2(X1, X2 are each independently O, S or Se)]
  • C07F9/3804—Phosphonic acids [RP(=O)(OH)2]; Thiophosphonic acids ; [RP(=X1)(X2H)2(X1, X2 are each independently O, S or Se)] not used, see subgroups
  • C07F9/3808—Acyclic saturated acids which can have further substituents on alkyl
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
  • C09K8/52—Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning
  • C09K8/528—Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning inorganic depositions, e.g. sulfates or carbonates
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
  • C02F2103/10—Nature of the water, waste water, sewage or sludge to be treated from quarries or from mining activities
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F2209/00—Controlling or monitoring parameters in water treatment
  • C02F2209/06—Controlling or monitoring parameters in water treatment pH

Definitions

• This invention relates to an improved method of scale inhibition, such as barium scale inhibition, which can be useful in connection with oil recovery and water treatment applications.
• the method broadly comprises the addition of a threshold amount of a selected amino acid alkyl phosphonic acid scale inhibitor.
• the scale inhibitor for use in the inventive method, can be selected from ⁇ -amino acid alkyl phosphonic acids and from amino acid species having a C 2 -C 20 hydrocarbon group connecting the carboxyl and amine moieties.
• ⁇ -amino acid alkyl phosphonic acids namely those which are substituted by: selected electron rich moieties containing, at least, one lone pair of electrons; aromatics wherein at least one of the carbon atoms has been substituted by a heteroatom; and compounds wherein the ⁇ - carbon atom is substituted by narrowly defined electron withdrawing moieties.
• WO 01/49756 discloses scale inhibitors comprising a hydro soluble copolymer consisting of major amounts of styrene sulfonic acid and vinyl sulfonic acid and, optionally, minor levels of non-ionizable monomers. These inhibitor combinations can be used in a squeeze treatment.
• US 5,112,496 describes compositions and methods for inhibiting oil field scale formation, particularly in high brine environments. Aminomethylene phosphonates containing 2 or more amine moieties, wherein substantially all of the available N-H functions have been phosphonated, are suitable for use.
• US 4,080,375 pertains to methylene phosphonates of amino- terminated oxyalkylates, having at least two amino groups, and the use thereof as scale inhibitors in marine oil recovery activities as well as their use for chelation in biological systems.
• the phosphonates can effectively sequester iron ions within the context of secondary oil recovery by means of water floods.
• US 5,263,539 describes method and composition technology useful for controlling and reducing the occurrence of scale in subterranean formations.
• the inhibitor compositions comprise an amino phosphonic acid and a copolymer of an alkenyl sulfonic acid compound and an ethylenically unsaturated monomer.
• the phosphonic acid can be represented by bishexamethylene triamine pentamethylene phosphonic acid.
• GB 2 306 465 pertains to a method of scale inhibition for use in oil field operations where water can contain high concentrations of alkaline earth metal salts such as barium salts.
• Preferred scale inhibitors can be represented by hydroxyl alkylated phosphonomethyl amines.
• US 6,022,401 discloses biodegradable corrosion inhibitors and anti-sealants for use in oil field fluid systems and other industrial water applications.
• the corrosion inhibitors/anti- scalants are represented by modified poly (aspartic acid) polymers and modified aspartic acid units.
• the modified aspartic acid can be substituted by selected side chains such as methyl phosphonic acids/salts.
• EP 0 408 297 describes scale inhibitors suitable for inhibiting calcium and barium scale formation in aquatic systems in which iron can be present.
• the inhibitor is represented by a methylene phosphonate, preferably carboxybisnitrilo tetra (methylene phosphonic acid), also known as urea (tetramethylene phosphonic acid).
• WO 01/85616 divulges a scale- and corrosion-inhibitor for application, inter alia, in water used in oilfield activities, containing, at least, one oxyalkylene unit and one phosphonate unit.
• the oxyalkylene can be represented by triethylene glycol or tetraethylene glycol.
• the phosphonate can be represented by vinyl phosphonic acid or vinylidene diphosphonic acid. In a preferred approach, the phosphonate and the oxyalkylene constituents can be reacted to thus yield a single compound for use.
• a method for producing N- phosphonomethylglycine by reaction of hexahydrotriazine with triacyl phosphate is described in WO 2003 000104.
• DDR patent 141 930 describes the manufacture of monophosphonated amino acids or the esters thereof.
• the amino acid moiety can, in the final product, be represented by ⁇ - alanine, ⁇ -alanine, phenylalanine and asparagine.
• the purpose of the study was the preparation of monophosphonates having one residual N-H function.
• DE 41 31 912 discloses mixtures of carboxyalkane aminomethane phosphonic acids prepared by reacting natural proteins, in particular from waste such as e.g. leather, corn and soya, egg white, skimmed and sugar-free milk powder, wool and silk waste, animal hair and other protein wastes.
• waste such as e.g. leather, corn and soya, egg white, skimmed and sugar-free milk powder, wool and silk waste, animal hair and other protein wastes.
• US 5,087,376 discloses a method of inhibiting the formation of scale- forming salts by means of a low level of diphosphonomethyl derivatives of taurine or cysteic acid.
• US 5 414 112 discloses N-bis (phosphonomethyl) amino acids and their use to control calcium carbonate scale in contact with industrial process waters.
• Specific compounds described are N, N-bis (phosphonomethyl) -L-glutamic acid, N, N- bis (phosphonomethyl) -L-serine and N, N, N', N'- bis (phosphonomethyl) -L-lysine.
• the L-lysine compound is represented by species carrying one phosphonomethyl moiety attached to one amino radical.
• the art in essence, aims at adding cumulative functionalities to thus secure additive results without providing remedy to known performance deficiencies, particularly within the context of marine oil recovery activities and/or water treatment applications, and/or avoiding multi component systems which are known to exhibit material deficiencies which are inherently attached to such known active combinations.
• percent or “%” as used throughout this application stands, unless defined differently, for “percent by weight” or “% by weight”.
• phosphonic acid and “phosphonate” are also used interchangeably depending, of course, upon medium prevailing alkalinity/acidity conditions.
• threshold is well known in the water treatment domain. The ability of very small amounts of scale inhibitors to keep large quantities of sealants in solution is known as the “threshold effect”. Or in other words, it is the prevention of precipitation from supersaturated solutions of sealants by ppm levels of inhibitor.
• ppm stands for "parts per million”.
• the method in accordance with this invention concerns scale control in aqueous systems adding a threshold amount of a scale inhibiting agent selected from the group of:
• a 1 has the formula
• A is independently selected from C 2 -C 20 linear, branched, cyclic or aromatic hydrocarbon chains, optionally substituted by Ci-Ci 2 linear, branched, cyclic or aromatic hydrocarbon groups, optionally substituted by OH, COOH and/or NH 2 moieties, and
• B is an alkylphosphonic acid moiety having from 1 to 6 carbon atoms in the alkyl group and x is an integer of from 1 to 10, preferably from 1 to 6,
• R and R' are independently selected from C1-C20 linear, branched, cyclic or aromatic hydrocarbon chains, optionally substituted by Ci-Ci 2 linear, branched, cyclic or aromatic hydrocarbon groups, optionally substituted by OH, NH 2 and/or COOH, and one of R or R' can be hydrogen
• R and/or R' are electron rich moieties containing, at least, one lone pair of electrons, which moiety is directly attached to an aromatic moiety by a covalent bond; or aromatics wherein at least one of the carbon atoms has been substituted by a heteroatom; and compounds, in the event R is -C(X) (R") (R'") and R' , R" and R'" are hydrogen wherein X is an electron withdrawing group selected from NO 2 , CN, COOH, SO 3 H, OH and halogen,
• a 2 is L-lysine, at least one L-lysine amino radical carries 2 (two) alkyl phosphonic acid moieties; and when
• a 2 is L-glutamic acid
• glutamic acid phosphonate represents a combination of from 50-90% by weight pyrrolidone carboxylic acid N-methylene phosphonic acid and from 10-50% by weight of L-glutamic acid diphosphonic acid, expressed on the basis of the reaction products;
• B is an alkylphosphonic acid moiety having from 1 to 6 carbon atoms in the alkyl group and y is an integer in the range of from 1 to 10, preferably from 1 to 6,
• a first essential aminoacid alkylphosphonic acid for use in the method of this invention can be represented by the formula :
• a 1 has the formula
• A is independently selected from C 2 -C 20 linear, branched, cyclic or aromatic hydrocarbon chains, (said chains being) optionally substituted by C 1 -C12 linear, branched, cyclic or aromatic hydrocarbon groups, (said groups and/or chains being) optionally substituted by OH, COOH and/or NH 2 moieties.
• A can be represented by a C 2 -C 16 linear hydrocarbon chain, optionally and preferably substituted by 1 to 3 NH 2 moieties.
• the selection of any number of carbon atoms in the hydrocarbon chain can constitute a desirable execution depending upon the choice of additional optional groups and/or optional moieties.
• the actual determination of preferred combinations is a routine measure, well known in the domain of the technology.
• a second essential aminoacid alkylphosphonic acid for use in the method of this invention can be represented by the formula:
• R and R' are independently selected from Ci-C 20 linear, branched, cyclic or aromatic hydrocarbon chains, (said chains being) optionally substituted by Ci-Ci 2 linear, branched, cyclic or aromatic hydrocarbon groups, (said groups and/or said chains being) optionally substituted by OH, NH 2 and/or COOH moieties, and one of R or R' can be hydrogen with the proviso of excluding structures which are not suitable for use within the context of the inventive technology.
• the aminoacid in the phosphonate inhibitor (ii) can be represented by D, L- alanine wherein y is 2, L-alanine wherein y is 2, L-lysine wherein y is in the range of from 2 to 4, L-phenylalanine wherein y is 2, L-arginine wherein y is in the range of from 2-6, L-threonine wherein y is 2, L-methionine wherein y is 2, L-cysteine wherein y is 2 and L-glutamic acid wherein y is 1 to 2.
• the L-glutamic acid alkylene phosphonic acid compound as such is, because of insufficient performance and stability, not suitable for use in the method of this invention.
• the L-glutamic acid alkylene phosphonic acid resulting from the methylenephosphonation of L-glutamic acid can be represented by a substantially binary mixture containing, based on the mixture (100%), a majority of a mono-methylene phosphonic acid derived from a carboxylic acid substituted pyrrolidone and a relatively smaller level of a dimethylene phosphonic acid glutamic acid compound.
• the reaction product frequently contains from 50 % to 90 % of the pyrrolidone carboxylic acid N-methylene phosphonic acid scale inhibitor and from 10 % to 50 % of the L-glutamic acid bis (alkylene phosphonic acid) compound.
• the binary mixture can also be prepared by admixing the individual, separately prepared, phosphonic acid compounds.
• the L-lysine carrying one alkylene phosphonic acid group attached to amino radical (s) represents not more than 20 molar % of the sum of the L-lysine carrying one and two alkylene phosphonic acid groups attached to amino radical (s).
• the L-lysine alkylene phosphonic acid is represented by a mixture of L- lysine carrying two alkylene phosphonic acid groups attached to (individual) amino radical (s) (lysine di) and L-lysine carrying four alkylene phosphonic acid groups (lysine tetra) whereby the weight ratio of lysine tetra to lysine di is in the range of from 9 : 1 to 1 : 1, even more preferred 7 : 2 to 4 : 2.
• Preferred aminoacids in the phosphonate inhibitors (i) include 7-aminoheptanoic acid, wherein x is 2, 6- aminohexanoic acid, wherein x is 2, 5-aminopentanoic acid, wherein x is 2, 4-amino butyric acid, wherein x is 2 and ⁇ - alanine wherein x is 2.
• Preferred aminoacids in the phosphonate inhibitors (i) can be prepared beneficially starting from lactams or other conventionally known materials; 7-aminoheptanoic acid can be used instead of 2- azacyclooctanone to make the corresponding diphosphonate.
• the preferred aminoacid starting materials are illustrated in the examples hereinafter.
• a mixture of stoichiometric proportions of the starting material aminoacid (1 mole), phosphorous acid (2 moles), aqueous hydrochloric acid (1.2 moles) is heated under stirring to 100 0 C, the formaldehyde (2 moles) is then gradually added over a period of 120-140 minutes at a temperature in the range of from 100-120 0 C.
• the reaction mixture is thereafter kept at 105-115 0 C for an additional 60-100 minutes. It is understood that the stoichiometric proportions of the starting materials can be varied to meet the desired degree of phosphonic acid substitution by reaction with the available N-H functions.
• the scale inhibitor for use in the method of this invention can be represented by selected combinations of aminoacid polyphosphonates of this invention in combination with a phosphonic acid selected from the group of: (a) amino (poly) alkylene polyphosphonic acids wherein the alkylene moiety contains from 1 to 20 carbon atoms; (b) hydroxyalkylene polyphosphonic acids wherein the alkylene moiety contains from 2 to 50 carbon atoms ; and (c) phosphono alkane polycarboxylic acids wherein the alkane moiety is in straight chain configuration containing from 3 to 12 carbon atoms.
• a phosphonic acid selected from the group of: (a) amino (poly) alkylene polyphosphonic acids wherein the alkylene moiety contains from 1 to 20 carbon atoms; (b) hydroxyalkylene polyphosphonic acids wherein the alkylene moiety contains from 2 to 50 carbon atoms ; and (c) phosphono alkane polycarboxylic acids wherein the alkane moiety is in straight
• aminoalkylene polyphosphonic acids having from 1 to 12 carbon atoms in the alkylene moiety
• phosphono alkane polycarboxylic acids have a straight chain alkane configuration having from 4 to 8 carbon atoms and wherein the molar ratio of phosphonic acid radical to carboxylic acid radical is in the range of from 1 : 2 to 1 : 4.
• Particularly preferred are polyphosphonic acids having from 2 to 8 phosphonic acid groups.
• aminotri methylene phosphonic acid
• N-oxide 1-hydroxyethylene (1, 1-diphosphonic acid); ethylenediamine tetra (methylene phosphonic acid); diethylene triamine penta (methylenephosphonic acid); hexamethylene diamine tetra (methylene phosphonic acid) ; hydroxyethyl aminobis (methylene phosphonic acid); N,N'-bis(3- aminopropyl) -ethylenediamine hexa (methylene phosphonic acid); and butane-2-phosphono-l, 2, 4-tricarboxylic acid.
• the ponderal ratio of aminoacid phosphonate to phosphonic acid is in the range of from 98 : 2 to 25 : 75, preferably from 90 : 10 to 50 : 50.
• a 2 can be represented by ⁇ -amino acids including specific natural amino acids such as e.g. occurring in animal species.
• Amino acids generally are the building blocks of proteins. There are over forty known amino acids about twenty of which are actually contained in e.g. animal tissue. Amino acids can be made by hydrolysis starting from proteins, by enzymatic fermentation and/or by chemical synthesis. This domain of the technology is eminently well known and all the individual technologies are abundantly documented in the literature. Suitable amino acids can be used in their D, D, L, and L forms as well as mixtures of the D and L forms.
• Preferred ⁇ -amino acids for use in the phosphonate inhibitors include: D, L- alanine; L-alanine; L-phenylalanine; L-lysine; L-arginine; L- methionine; L-cysteine; L-threonine/ and L-glutamic acid.
• a water insoluble product is obtained; it is believed to be due to the reaction of formaldehyde with tyrosine resulting in the formation of methylene bridges between aromatic moieties; 2.
• the reaction of L-tryptophan (1 eq.) with H 3 PO 3 (2 eq.) and formaldehyde (2.2 eq. ) in the presence of HCl (2.5 moles) between 107 and 111 0 C does not lead to the corresponding bis (methylene phosphonic acid).
• 31 P NMR analysis only shows signals for the starting phosphorous acid with traces of phosphoric acid.
• a water insoluble product is obtained; it is believed to be due to the reaction of formaldehyde with tryptophan resulting in the formation of methylene bridges between aromatic moieties; and
• the latter product has been shown by 31 P NMR to decompose under the reaction conditions into fumaric acid and imino bis (methylene phosphonic acid) which is itself converted into ATMP.
• the amino acid alkylphosphonate scale inhibitors for use in the inventive method can be prepared by reacting one or more of the available N-H functions of the aminoacid with phosphorous acid and formaldehyde, in the presence of hydrochloric acid, in aqueous medium having a pH of generally less than 4 by heating that reaction mixture, at a temperature of usually greater than 70 0 C for a sufficient time to complete the reaction.
• This kind of reaction is conventional and well-known in the domain of the technology and examples of the novel phosphonate compounds have been synthesized, as described below, via the hydrochloric acid route.
• the aminoacid phosphonates can be made under substantial exclusion of hydrohalogenic acid and corresponding by-products and intermediates.
• the aminoacid phosphonates can be manufactured in presence of not more than 0.4 %, preferably less than 2000 ppm, of hydrohalogenic acid, expressed in relation to the phosphorous acid component (100 %) by reacting:
• (d) stands for the number of moles of catalyst multiplied by the number of available protons per mole of catalyst, followed by recovering the aminoacid phosphonates formed in a manner known per se.
• the catalyst has a pKa equal or inferior to 3.1, preferably equal or inferior to 2.75, most preferably equal or inferior to 1.9, said catalyst being homogeneously compatible with the reaction medium.
• the pKa can be expressed as follows:
• the term "homogeneous" catalyst means that the catalyst, suitable for use, forms a single liquid phase within the reaction medium under the reaction conditions.
• the homogeneous nature of a catalyst can be ascertained routinely by e.g. visible inspection of precipitation or phase separation properties.
• Preferred catalyst species can be selected from sulphuric acid, sulphurous acid, trifluoroacetic acid, trifluoromethane sulfonic acid, methane sulfonic acid, oxalic acid, malonic acid, p-toluene sulfonic acid and naphthalene sulfonic acid.
• the homogenous reaction is preferably conducted at a temperature in the range of from 70 0 C to 150 0 C with an approach selected from:
• the aminoacid phosphonates for use herein can be prepared under substantial exclusion of hydrohalogenic acid, specifically in the presence of not more than 0.4 %, preferably less than 2000 ppm, of hydrohalogenic acid, expressed in relation to the phosphorous acid component (100 %), by reacting: (a) phosphorous acid; (b) an aminoacid; and (c) formaldehyde; in reactant ratios as follows: (a) : (b) of from 0.05 : 1 to 2 : 1; (c) : (b) of from 0.05 : 1 to 5 : 1; and (c) : (a) of from 5 : 1 to 0.25 : 1; wherein (a) and (c) stand for the number of moles to be used and (b) represents the number of moles multiplied by the number of N- H functions in the amino acid, in the presence of a heterogeneous, with respect to the reaction medium, Broensted acid catalyst selected from the group consisting of:
• solid acidic metal oxide combinations as such or supported onto a carrier material
• cation exchange resins selected from the group comprising copolymers of styrene, ethyl vinyl benzene and divinyl benzene, functionalized so as to graft SO 3 H moieties onto the aromatic group and perfluorinated resins carrying carboxylic and/or sulfonic acid groups
• organic sulfonic and carboxylic Broensted acids which are substantially immiscible in the reaction medium at the reaction temperature
• heterogeneous heteropolyacids of the general formula H x PM y O 2 wherein P is selected from phosphorus and silicon and M is selected from W and Mo and combinations thereof
• Suitable Broensted catalysts are fluorinated carboxylic acids and fluorinated sulfonic acids having from 6 to 24 carbon atoms in the hydrocarbon chain.
• a specific example of a suitable catalyst is represented by perfluorinated undecanoic acid.
• suitable heterogeous acid catalysts can be represented by cation exchange resins.
• resins comprise copolymers of styrene, ethylvinyl benzene and divinyl benzene functionalized such as to graft SO 3 H groups onto the aromatic groups.
• heterogeneous Broensted catalyst can be used in many operational manufacturing arrangements well known in the domain of the technology.
• heterogeneous means that the Broensted catalyst is substantially insoluble in the reaction medium at the reaction conditions or substantially immiscible, thus liquid, in the reaction medium at the reaction conditions.
• the heterogeneous reaction is preferably conducted at a temperature in the range of from 70 to 150 0 C for a time sufficient to complete the reaction.
• the essential formaldehyde component is a well known commodity ingredient.
• Formaldehyde generally is produced and sold as water solutions containing variable, frequently minor, e.g. 0.3-3 %, amounts of methanol and are reported on a 37 % formaldehyde basis.
• Formaldehyde solutions exist as a mixture of oligomers.
• the formaldehyde component can also be represented by aldehydes and ketones having the formula wherein Ri and R 2 can be identical or different and are selected from the group of hydrogen and organic radicals.
• the material When Ri is hydrogen, the material is an aldehyde. When both Ri and R 2 are organic radicals, the material is a ketone.
• Species of useful aldehydes are, in addition to formaldehyde, acetaldehyde, caproaldehyde, nicotinealdehyde, crotonaldehyde, glutaraldehyde, p-tolualdehyde, benzaldehyde, naphthaldehyde and 3-aminobenzaldehyde.
• Suitable ketone species for use herein are acetone, methylethylketone, 2- pentanone, butyrone, acetophenone and 2-acetonyl cyclohexanone .
• the phosphorous acid reactant is preferably prepared, in a known manner, under substantial exclusion of halogen, by contacting elemental phosphorus, such as tetraphosphorus, with water at a temperature below 200 0 C, in the presence of a catalyst effective to promote oxidation of phosphorus, by reaction with water; or by contacting P(V) species with a reducing agent, such as hydrogen, in the presence of a reducing catalyst; or by contacting a hydrolysis feed mixture comprising phosphate esters and phosphonate esters with liquid water and steam to thereby hydrolyze the phosphonate esters to phosphorous acid.
• elemental phosphorus such as tetraphosphorus
• P(V) species with a reducing agent, such as hydrogen
• a hydrolysis feed mixture comprising phosphate esters and phosphonate esters with liquid water and steam to thereby hydrolyze the phosphonate esters to phosphorous acid.
• Scale formation such as carbonate and sulphate scales
• calcium sulphate and especially barium sulphate and strontium sulphate can become a major problem in the operation of the well.
• sulphate scales prevail upon seawater injection during the enhanced oil recovery treatment, milder pH conditions, prevailing closer to the surface, pressure differences and high temperatures in the down-hole formation usually lead to the formation of mixtures of carbonate and sulphate scale.
• the scale inhibitors shall therefore exhibit performance over a broad range of conditions such as can occur in the oil wells and production facilities.
• the inhibitor can be introduced into the oil bearing formation by any suitable treatment including a "squeeze" treatment.
• a "squeeze" treatment In general such a method for oil recovery requires injecting into a marine oil well an aqueous solution of the aminoacid phosphonic acid scale inhibitor of this invention in a usual level of from 0.1 to 100000 ppm . Frequently, the production oil well activity is stopped and the inhibitor solution is injected into the oil well formation. It was established that the scale inhibitors in accordance with this invention can be used effectively and singly.
• the squeeze treatment generally consists of injecting a scale inhibitor solution into the wellbore of the producing well to place the inhibitor into the formation.
• the scale inhibitor released from the formation is present, in the return water, in a concentration of, at least, 0.1, usually at least 0.5, frequently from 10 to 100 ppm to thus exhibit effective scale control and consequently secure oil well production continuity with levels of inhibitor means reduced by one order of magnitude compared to actually prevailing practice.
• a beneficial method for oil recovery can be done by injecting into marine oil wells an aqueous solution of the aminoacid phosphonic acid compound of the invention in a level of from 0.1 to 100000 ppm.
• the method can be conducted by continuously injecting into the well an aqueous solution of from 0.1 to 800 ppm of the aminoacid phosphonic acid compound.
• the continuous injection frequently means that the scale inhibitor solution is injected into the water injection well.
• the continuous injection can also apply to the surroundings of the production well such as the well-head arrangement including under-water equipment for example pumps and pipes.
• the aminoacid scale inhibitors of this invention can also be used in squeeze oil recovery methods.
• Such squeeze method comprises, in sequence: stopping the production wellbore activity; introducing through the production wellbore the aqueous treatment solution containing the aminoacid phosphonic acid scale inhibitor in a level of from 100 to 100000 ppm; injecting sea water through the production wellbore to place the scale inhibitor within the targeted area of the formation; restarting the oil extraction activity; and producing return fluids, containing oil and return water, through the production wellbore.
• the inventive method also contemplates the use of the aminoacid phosphonic acid inhibitors herein in scale forming water systems containing usually more than 100 mg/1 of barium and/or strontium hardness and/or calcium carbonate and having a pH generally within the range of from 2-10. To that effect, of from 0.1 to 800 ppm, preferably of from 0.2 to 100 ppm, of the aminoacid phosphonate scale inhibitor is added to the water system.
• the individual aminoacid phosphonate scale inhibitors can, in one execution, be used substantially singly, or in the event they are used as a mixture of more than one (i) species or a mixture of more than one (ii) species or as a mixture of (i) and (ii) species, then it was observed that one individual inhibitor in accordance with this invention shall constitute, on a ponderal basis, at least 50 %, usually 60 % or more of the mixture of inhibitors of this invention. It was observed that aminoacid mixtures originating from protein hydrolysates are not well suitable for use in the method herein due to, inter alia, interactions of the various species which can adversely affect performance.
• Preferred scale inhibitors herein, particularly for application within the context of oil producing wells shall have a thermal decomposition, measured at 140 0 C, of less than about 10 %.
• the scale inhibitor performance of the aminoacid alkyl phosphonates suitable for use in the method of this invention can be quantified thereby using comparative testing methods as follows.
• solution 2 -prepare synthetic North Sea water having a pH of 5.5 (solution 2) ; -prepare a sample of 1 % active acid phosphonate by mixing 1 g of solution 1 with 19 g of solution 2;
• This test assesses sea water compatibility of the phosphonates added at: 100; 1000; 10000; and 50000 ppm to North Sea water after 22 hours at 90 0 C. Calcium left in solution is measured by ICP.
• Vi ppm Ca found in the solution with the phosphonate.
• the test is carried out by determining the amount of BaS ⁇ 4 and SrSO 4 that has precipitated after 22 hours at 90 0 C in a 50/50 mixture of synthetic North Sea water and Formation water containing the phosphonates to be tested at 5 different concentrations.
• the amount of soluble Ba and Sr ions is determined by ICP.
• the results stand for the minimum phosphonate concentration for 100 % barium sulphate scale inhibition or give the scale inhibition at 100 ppm loading of phosphonate. Test details are as follows:
• V 0 ppm Ba (or Sr) found in the blank solution
• Vi ppm Ba (or Sr) found in the solution with the inhibitor
• V 2 ppm Ba (or Sr) present in the Formation water.

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• Detergent Compositions (AREA)
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• Agricultural Chemicals And Associated Chemicals (AREA)
• Lubricants (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)

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• 2006
  • 2006-08-09 EP EP20060016597 patent/EP1886976A1/en not_active Withdrawn
• 2007
  • 2007-05-25 MX MX2012012840A patent/MX339539B/es unknown
  • 2007-05-25 EP EP07725578A patent/EP2057099A2/en not_active Ceased
  • 2007-05-25 JP JP2009523157A patent/JP5623741B2/ja active Active
  • 2007-05-25 RU RU2009107855A patent/RU2436738C2/ru active
  • 2007-05-25 MX MX2009001448A patent/MX2009001448A/es active IP Right Grant
  • 2007-05-25 US US12/376,896 patent/US8461088B2/en active Active
  • 2007-05-25 DK DK17151222.1T patent/DK3178792T3/da active
  • 2007-05-25 EP EP17151222.1A patent/EP3178792B1/en active Active
  • 2007-05-25 AU AU2007283161A patent/AU2007283161A1/en not_active Abandoned
  • 2007-05-25 CN CN201210005580.4A patent/CN102674571B/zh active Active
  • 2007-05-25 CA CA 2659813 patent/CA2659813C/en active Active
  • 2007-05-25 RU RU2011133562/05A patent/RU2576053C2/ru active
  • 2007-05-25 WO PCT/EP2007/004682 patent/WO2008017338A2/en not_active Ceased
  • 2007-05-25 NZ NZ59944007A patent/NZ599440A/xx unknown
  • 2007-05-25 CN CN2007800294982A patent/CN101500951B/zh active Active
  • 2007-05-25 BR BRPI0716488-2A patent/BRPI0716488B1/pt active IP Right Grant
• 2009
  • 2009-02-02 NO NO20090501A patent/NO345314B1/no unknown
  • 2009-02-06 ZA ZA2009/00884A patent/ZA200900884B/en unknown
• 2013
  • 2013-06-05 US US13/910,578 patent/US9108866B2/en active Active
• 2014
  • 2014-08-14 JP JP2014165051A patent/JP5925256B2/ja active Active

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