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Methylenephosphonic acid

Phosphonic acid is an intermediate in the production of alkylphosphonates that are used as herbicides and as water treatment chemicals for sequestration, scale inhibition, deflocculation, and ion-control agents in oil weUs, cooling tower waters, and boiler feed waters. For example, aqueous phosphonic acid reacts with formaldehyde and ammonium chloride in the presence of hydrochloric acid to yield aminotri(methylenephosphonic acid) [6419-19-8]. [Pg.374]

STPP = sodium tripolyphosphate NTA = nitnlotriacetic acid EDTA = ethylenediaminetetraacetic acid EDTPO = ethylenediaminetetra(methylenephosphonic acid) (see Table 1). [Pg.385]

Phosphonates, especially aminotri(methylenephosphonic acid) (ATMP) and l-hydroxyethylidene-l,l-diphosphonic acid (HEDP). Organophosphonates have the ability to control both scaling and corrosion by a combination of chelation and crystal nuclei growth supression (threshold) mechanisms they also provide scale control by crystal distortion. [Pg.432]

Aminotri(methylenephosphonic acid) [ATMP or AMP] is the least expensive phosphonate. It is a good, general-purpose, cost-effective scale inhibitor an effective chelant and the most thermally stable of all the common phosphonates. It is satisfactory up to at least 700 psia. However, if fed as a concentrate AIMP may easily form insoluble calcium phosphonate and it may also affect copper. ATMP has a sequestration value of 870 mg CaC03/g product at a pH level of 11 and for iron, a sequestration value of 150 mg Fe/g product at a pH level of 10. The pentasodium salt has a MW of 409. Examples include Dequest 2000/2006, Mayoquest 1230, Phos -2, Briquest 301-50A, Unihib 305, and Codex 8503. [Pg.449]

ABMA ACH AGR AMP AMP American Boiler Manufacturers Association aluminum chlorhydrate advanced gas-cooled reactor aminotri-(methylenephosphonic acid) 2-amino-2-methyl-l-propanol, AKA isobutanolamine... [Pg.981]

AO AP AP/AO ASB ASME ASTM 1-AP ATMP AVAT AVP All-Organic 5-aminopentanol All-Polymer/All-Organic Shell Boiler Makers Association (UK) American Society of Mechanical Engineers American Society for Testing and Materials 1 -aminopyrrolidine aminotri-(methylenephosphonic acid) All-Volatile alkaline treatment All-Volatile programs... [Pg.981]

Aminopolymethylenephosphonic acids are obtained when in place of monoamine di- and polyamines are used. Best known is ethylenediiminotetra-methylenephosphonic acid, used as a lime soap dispersant [131-133] see Eqs. (78) and (79) ... [Pg.580]

Polyethers with a methylenephosphonic acid diester group, e.g., from diols with epoxypropanephosphonic acid diesters, are used in the production of plastics as flame-resistant conditioning [150]. [Pg.583]

When there is a limitation of the phosphorus content in detergents of 1%, then addition of phosphonates can act as an alternative solution in combination with other polyvalent ion-binding substances. Especially when magnesium is a cause of water hardness the zeoliths can form precipitations. But phosphonates, like hydroxyethanephosphonic acid (HEDP) and ethylenediaminetetra-methylenephosphonic acid (EDTMP), are able to sequester magnesium ions as well. [Pg.597]

Yamabe, K., Jyo, A., Development of specific adsorbent for fluoride based on metal ion loaded methylenephosphonic acid resin, in Proceedings of the 12 th International Conference on Chemistry for the Protection of the Environment, eds. Z. Cao, and L. Pawlowski, Nanjing University Press, Nanjing, China, 1999, pp.230-237, ISBN 7-305-03345-6/0-233. [Pg.50]

Jyo A., Yamabe K., Egawa H., Behavior of methylenephosphonic acid chelating resin in adsorption and elution of molybdenum (VI), Sep. Sci. Technol. 31,1996,513-522. [Pg.64]

Fig. 10. (A) Structure and (B) fluorescence emission spectrum of Tb-[N-2-pyridylmethyl)-N, N",N" -tris(methylenephosphonic acid butyl ester)-l,4,7,10-tetraazacyclododecane] (Tb-PCTMB). Reprinted with permission from [126], Copyright 1999 American Chemical Society... Fig. 10. (A) Structure and (B) fluorescence emission spectrum of Tb-[N-2-pyridylmethyl)-N, N",N" -tris(methylenephosphonic acid butyl ester)-l,4,7,10-tetraazacyclododecane] (Tb-PCTMB). Reprinted with permission from [126], Copyright 1999 American Chemical Society...
Iron(III)-pyrophosphate looks promising as an alternative to iron(III)-carbohydrate preparations for parenteral administration for treatment of anemia.Kinetics of removal of iron from transferrin (tf) by pyrophosphate (pp) were found to be biphasic under certain conditions, with the rapid first phase attributed to the formation of a pp—Fe—tf—CO intermediate.A later study of the kinetics of removal of iron from transferrin employed pyrophosphate and tripodal phosphonates such as nitrilotris(methylenephosphonic acid), N(CH2P03H2)3. For the tripodal ligands there are parallel first-order and saturation pathways, with the latter dominant (contrast the exclusively first-order reaction of ferritin with nitrilotriacetate) for pyrophosphate the paths are roughly equal in importance. The saturation kinetics suggest that tfiFe-phosphonate intermediates play an important role in the kinetics. [Pg.490]

The three most commonly used phosphonates are diethylenetriaminepenta (methylenephosphonic acid) (DTPMP), ethylenediaminetetra(methylenephospho-nic acid) (EDTMP), and hydroxyethyldiphosphonic acid or etidronic acid (HEDP) (Figure 10.3). DTPMP and EDTMP are also powerful chelants that complex strongly with most metal ions to form six-coordinate complexes, and for this reason are often... [Pg.284]

Mono and bis complexes of Pr3+ and Nd3+ in aqueous solutions of iminodiaceticmono-methylenephosphonic acid have been studied over the pH range 1-12 by visible spectroscopy and association constant values determined.365... [Pg.1085]

Aminotri(methylenephosphonic acid) (ATMP or AMP) is the lowest cost phosphonate. It is a good general-purpose scale inhibitor. It is also an effective chelant and can provide good corrosion inhibition when in combination with zinc or phosphates. [Pg.157]

Manganese(II) is normally not readily autoxidized, but when it is complexed by, e.g., nitrilobis(methylenephosphonic acid) ready autoxidation by 02 occurs (Nowack and Stone 2000). Whether under such conditions OH are set free as in the autoxidation of EDTA-complexed Fe(II) (Yurkova et al. 1999), is not yet know. [Pg.36]

Nowack B, Stone AT (2000) Degradation of nitrilotris(methylenephosphonic acid) and related (amino)phosphonate chelating agents in the presence of manganese and molecular oxygen. Environ SciTechnol 34 4759-4765... [Pg.44]

HSA binding not only interferes with the inner-sphere water molecules, but also the outer-sphere. DOTP( 1,4,7,10-tetraazacyclododecane-N, N , N , A "-tetrakis(methylenephosphonic acid) derivatives have no inner-sphere water molecule, and rely on the outer-sphere mechanism. This property allows the study of how HSA binding sites affect relaxivity, which shows that differences in r are solely due to the nature of the binding sites [77,78]. [Pg.419]

Stability constants for [Ln(dotp)] complexes have been determined log K ranges from 27.6 (La) to 29.6 (Lu) (dotp = 1,4,7,10-tetraazaccyclododecane-l,4,7,10-tetrakis(methylenephosphonic acid). In view of its use as a cation-shift reagent, it is notable that Na-NMR studies show NH4+ and K+ compete effectively with Na" " for the binding sites on [Tm(dotp)] . Ca " " and Mg also complex with [Tm(dotp)]. ... [Pg.150]

Phosphorous acid and formaldehyde react with ammonia or a compound with an amino- or imino-group producing an aminomethylenephosphonic acid. Phosphonomethylation occurs in an acid medium and is catalyzed by chloride, which is the reason why hydrolyzed phosphorus(lll) chloride is often used as the phosphorus-containing raw material. As a rule all the N-H- hydrogen atoms are replaced by a CH2P(0)(0H)2- group. Thus with ammonia, amino-tri(methylenephosphonic acid) (AMP) is formed ... [Pg.99]

Group 1 Systems. NMR spectroscopy was used to follow the binding of alkali metal ions to the Ga(III) complex of the hexadentate ligand formed by linking 3 sets of 3-hydroxy-4( 1 //(-pyridinonc and ethylenoxy chains to tris(car-boxyethoxymethyljethane.1016 31P NMR data revealed that alkali metal ions (Li - Cs) coordinate with nitrilotris(methylenephosphonic acid) (H6L), to form MHL4 and ML5 in solution.1017... [Pg.74]

Fig. 3-104. Separation of polyphosphonic acids upon application of phosphorus-specific detection. - Separator column IonPac AS7 eluent 0.17 mol/L KC1 + 0.0032 mol/L EDTA, pH 5.1 flow rate 0.5 mL/min detection photometry at 410 nm after hydrolysis and derivatization with vana-date/molybdate injection 50 pL, l-hydroxyethane-l,l-diphosphonic acid (HEDP), aminotris-(methylenephosphonic acid) (ATMP), ethylenediamine-tetramethylenephosphonic acid (EDTP), l,l-diphosphonopropane-2,3-dicarboxylic acid (DPD), and 2-phosphonobutane-l,2,4-tricarboxylic add (PBTC) (taken from [84]). Fig. 3-104. Separation of polyphosphonic acids upon application of phosphorus-specific detection. - Separator column IonPac AS7 eluent 0.17 mol/L KC1 + 0.0032 mol/L EDTA, pH 5.1 flow rate 0.5 mL/min detection photometry at 410 nm after hydrolysis and derivatization with vana-date/molybdate injection 50 pL, l-hydroxyethane-l,l-diphosphonic acid (HEDP), aminotris-(methylenephosphonic acid) (ATMP), ethylenediamine-tetramethylenephosphonic acid (EDTP), l,l-diphosphonopropane-2,3-dicarboxylic acid (DPD), and 2-phosphonobutane-l,2,4-tricarboxylic add (PBTC) (taken from [84]).

See other pages where Methylenephosphonic acid is mentioned: [Pg.379]    [Pg.479]    [Pg.788]    [Pg.781]    [Pg.580]    [Pg.107]    [Pg.900]    [Pg.49]    [Pg.33]    [Pg.22]    [Pg.379]    [Pg.159]    [Pg.167]    [Pg.185]    [Pg.461]    [Pg.112]    [Pg.430]    [Pg.224]    [Pg.30]    [Pg.5186]    [Pg.491]    [Pg.428]   
See also in sourсe #XX -- [ Pg.246 , Pg.274 , Pg.282 ]




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