Nitrilotrimethylphosphonic Acid Research Articles

Highly efficient removal of phosphonates by ferrate-induced oxidation coupled with in situ coagulation

Phosphonates, as a kind of important organic phosphorus in wastewater, should be removed in terms of their environmental risks. Unfortunately, traditional biological treatments fail to remove phosphonates effectively due to their biological inertness. The reported advanced oxidation processes (AOPs) usually require pH adjustment or coupling with other technologies to achieve high removal efficiency. Thus, a simple and efficient method for phosphonate removal is urgently needed. Herein, ferrate was found to remove phosphonates effectively in one-step under near-neutral circumstances by coupling oxidation and in-situ coagulation. Nitrilotrimethyl-phosphonic acid (NTMP), a typical phosphonate, could be efficiently oxidized by ferrate to release phosphate. The fraction of phosphate release increased with increasing ferrate dosage and reached 43.1% when 0.15 mM ferrate was added. Fe(VI) was responsible for NTMP oxidation, while Fe(V), Fe(IV) and ⋅OH played a minor role. Ferrate-induced phosphate release facilitated total phosphorus (TP) removal, because the phosphate is more easily removed via ferrate-resultant Fe(III) coagulation than the phosphonates. The coagulation removal of TP could reach up to 90% within 10 min. Furthermore, ferrate exerted high removal efficiencies for other commonly used phosphonates with approximately or up to 90% TP removal. This work provides a one-step efficient method to treat phosphonate-containing wastewaters.

Water wells: Sustainable usage and rehabilitation technology

Uzbekistan is one of the most water resources limited regions and it needs better sustainable water management. The global ecological problem as the Aral Sea disaster makes it more urgent not only for one nation but also for the all CentralAsian region. Region needs to be developed by following SDG and the same time to save water resources. The balance of the ground water resources in the region is environmentally safe and enough by quantity and also hydrologically. It is due to the use of huge number of the water wells as artesian and also drainage wells. At the UZWATER National center of SamSACU the studies on the clogging deposits as the chemically and mineralogically multicomponent complex composition particles and their removal/declogging rehabilitation of the water wells are carried out. A rehabilitation technology effective for the region with dry and hot climate and environmentally safe water wells by using complex reagents such as oxyethylidenediphosphonic acid and nitrilotrimethylphosphonic acid in combination with carbon dioxide will help to remove of the clogging deposits and a stable filtration process and work of the water wells.

The possible use of tin ion discharge inhibition in bronze electroplating from an electrolyte based on nitrilotrimethylphosphonic acid

The possible use of tin ion discharge inhibition in bronze electroplating from an electrolyte based on nitrilotrimethylphosphonic acid

Исследование процесса обработки черносмородинового и клюквенного спиртованных соков тринатриевой солью нитрилотриметилфосфоновой кислоты

На основании проведенных исследований установлено, что обработка черносмородинового и клюквенного спиртованных соков нитрилотриметилфосфоновой кислотой позволяет снизить концентрацию железа до нормы, установленной требованиями ТР ТС 029/2012 «Требования безопасности пищевых добавок, ароматизаторов и технологических вспомогательных средств» - не более 10 мг/дм, и повысить прозрачность спиртованных соков. Based on the conducted studies, it was found that the treatment of blackcurrant and cranberry alcoholic juices with nitrilotrimethylphosphonic acid reduces the concentration of iron to the norm established by the requirements of Customs Union Technical Regulations «Safety requirements of food additives, flavorings and processing aids» (CU TR 029/2012) - no more than 10 mg/dm and increases the transparency of alcoholic juices.

Influence of chemical composition on the proton conductivity of microporous organic polymers entrapped in nitrilotrimethylphosphonic acid

The construction of acid–base interactions is critical for developing proton-conducting COF materials with high loading and stable electrolytes, which is influenced by the chemical composition of conductors.

A study of corrosion processes in a demineralized aqueous medium in the presence of bacterial cells

Our earlier results indicate the feasibility of considering the microbiological contamination of closed and reversible cooling and water supply systems, given the effect of the microbial cells on the corrosion processes taking place there. The results show a possibility of transition metal ions acting as regulators and modifiers of microorganisms’ growth processes under conditions of an osmotic stress and starvation.The aim of the present work is to study the effect of transition d-metal ions (Zn2+ and Cr3+), both separately and in the presence of known antiskalants, oxyethylenediphosphonic acid (OEDFh) and nitrilotrimethylphosphonic acid (NTMFh), on the effectiveness of the corrosion protection and the course of the biological corrosion in a demineralized environment.Microorganisms belonging to different systematic affiliations were selected for the study of the biocorrosion processes: Bacillus sp. and Pseudomonas sp. These microorganisms belonged to different physiological groups of bacteria and had opposite types of life strategies. They differred significantly in their ability to survive under the influence of various factors. They could exist in closed systems of water consumption (with sharp temperature changes, oxygen starvation, a presence of toxic substances used for water conditioning). Bacillius and Pseudomonas strains were cultured on commonly used agar media, after which a cell suspension was prepared. For all bacterial strains used, the seeding dose was 108 cells‧cm-3. It was determined using turbidometric control methods and bacterial density standards. The effect of the microorganisms on the corrosion processes was followed in stationary bioreactors of a volume of 125 cm3. A solution of 0.1 % NaCl was added as a model medium to which corrosion inhibitors (Zn2+, Cr3+, OEDPh and NTMPh) were added at a concentration of 5 mg‧dm-3. At each stage of preparation, the suspension was thoroughly mixed, after which the metal samples were introduced to the reactor in the form of electrodes so that the entire surface of the electrode was completely immersed in the water. The metal samples were made of St 20 carbon steel. Each study of model water with metal plates was of 3 weeks duration. The intensity of the corrosion process was evaluated once a week. The rate of the biological corrosion was determined by the gravimetric method. The inhibition factor (j) and the degree of the corrosion protection (Z, %) of the samples in presence of corrosion inhibitors and bacteria were calculated. The negative value of this indicator indicated a change of the direction of the process, i.e. an activation of the corrosion process.The obtained data show that the presence of microorganisms significantly modifies the anti-corrosion effect of the heavy metal ions. The range offluctuations of the degree of the corrosion protection in presence of bacteria of the genus Pseudomonas is greater than that of the genus Bacillus. The dynamics of the protective effect in presence of both strains is characterized by significant changes (a decrease and a subsequent gradual increase of the degree of the corrosion protection). The highest intensity of the corrosion process is observed during the first week of the interaction in a model environment containing bacterial cells and anticorrosive agents. Then, the direction of the process changed and there was shown a slight protective effect at the 5-15 up to 36 % level. It is also demonstrated that the anti-corrosion compositions containing NTMPh provide a greater increase of the corrosion process rate in presence of microorganisms.The study of the presence of microorganisms on the corrosion proceeding demonstrates their ability to provide a significant effect. The bacteria can activate the corrosion process, which complicates the inhibitors behavior.

Phosphonic acid loaded covalent imine networks for proton-conducting membranes

Triazine-based covalent organic polymers (COPs) have substantially concerned as a hopeful proton-conducting medium. Generally, encapsulating protonphore molecules into porous COPs is a potential tactics to improve the proton conductivity (PC). Herein, the COP-based proton conductor is fabricated by immobilizing nitrilotrimethylphosphonic acid (NTP) molecules into the pores of nitrogen-rich covalent imine network (CIN) to give NTP/CIN, further followed by blending NTP/CIN as filler into chitosan (CS, a deacetylated form of chitin) to form hybrid membranes (NTP/CIN@CS). NTP/CIN@CS possesses relatively higher PC of 7.8 × 10−3 S cm−1 under ~98% RH at 328 K, ranging in the most conductive COF-based hybrids, which is 71- and 17-folds than those of pristine CS and CIN@CS. The basic functional units contained from CIN backbone, phosphate groups derived from NTP and amino and hydroxyl groups at CS matrix, along with water, conduct the transfer of proton in the hybrid membrane. The relatively high water uptake (W.U.) and ion exchange capacity (IEC) of NTP/CIN@CS also contribute to form continuous and steady H-transport channel, and thus greatly enhance PC. The inspiration that nitrogen-rich COF framework federated with proton carrier tenders a new path to discern solid-state electrolyte.

Batch studies of phosphonate adsorption on granular ferric hydroxides

Phosphonates are widely used in various industries. It is desirable to remove them before discharging phosphonate-containing wastewater. This study describes a large number of batch experiments with adsorbents that are likely suitable for the removal of phosphonates. For this, adsorption isotherms for four different granular ferric hydroxide (GFH) adsorbents were determined at different pH values in order to identify the best performing material. Additionally, the influence of temperature was studied for this GFH. A maximum loading for nitrilotrimethylphosphonic acid (NTMP) was found to be ∼12 mg P/g with an initial concentration of 1 mg/L NTMP-P and a contact time of 7 days at room temperature. Then, the adsorption of six different phosphonates was investigated as a function of pH. It was shown that GFH could be used to remove all investigated phosphonates from water and, with an increasing pH, the adsorption capacity decreased for all six phosphonates. Finally, five adsorption-desorption cycles were carried out to check the suitability of the material for multiple re-use. Even after five cycles, the adsorption process still performed well.

Thermodynamics of the Dissolution of Nitrilotrimethylphosphonic Acid in Water

Thermodynamics of the Dissolution of Nitrilotrimethylphosphonic Acid in Water

EFFECT OF IONS OF TRANSITIONAL d-METALS ON THE DYNAMICS OF MICROORGANISM SURVIVAL IN THE PRESENCE OF PHOSPHONIC ACIDS

Metal corrosion is a complex process that can be substantially modified by the influence of various factors, including the presence of microorganisms in water-circulation systems. Proceeding from the above, in this work the effect of ions of transitional d-metals on the dynamics of microorganism survival was studied in the presence of well-known antisludge agents - oxyethylenediophosphonic acid (OEDFA) and nitrilotrimethylphosphonic acid (NTMFA). Microorganisms of the various systematic groups belonging also to the different physiological groups and having opposite types of life strategies have been selected for our researching: Bacillius sp. and Pseudomonas sp. They differ significantly in terms of survival opportunities under the influence of factors that can exist in closed water consumption systems (sudden temperature changes, oxygen starvation, the presence of toxic substances added to water for its conditioning). The influence of microorganisms on corrosion processes was studied in the stationary bioreactors in a volume of 125 ml. A solution of 0.1% NaCl was used as a model environment, to which corrosion inhibitors - d-metals (Zn2+ and Cr3+) and phosphonic acids (OEDFA and NTMFA) in concentration of 5 mg/dm3 had been adding.The results of our research have shown the possibility of transition metal ions act as regulators and modifiers of growth processes of microorganisms that are under conditions of osmotic stress and fasting. Representatives of the studied groups of the microorganisms demonstrated a different level of resistance to the presence of phosphonic acids and Zn2+ and Cr3+ ions at a concentration of 5 mg/dm3 in the model solution.So, in case of cultivating microbial cells in an osmotically unfavorable environment for them (0.1% NaCl solution without the addition of organic substances), almost linear dynamics of the dying out of bacterial cells of both species was observed without manifestations of significant difference. A similar effect may be due to the absence of nutrient elements in the model solution or the lack of osmotic-active components. Adding to the cultivation medium of phosphonic acids at a concentration of 5 mg/dm3 did not lead to statistically significant changes in the obtained dependencies. The greatest changes in the dynamics of microbial cell survival were observed when chromium ions were added to the cultivation medium, which was expressed as a decrease in the percentage of viable cells of Bacillus sp. (up to 24%) and a significant increase in survival among Pseudomonas sp. (up to 78%) compared to the survival without the addition of metal ions. The obtained results indicate the expediency of taking into account the possibility of the existence of microbiological contamination in reversible water supply systems in view of the influence of microbial cells on the processes of corrosion that occur there.Key words: ions of transient d-metals, phosphonic acids, microorganisms, survival dynamics, closed water supply systems

Optimized Procedure for Determining the Adsorption of Phosphonates onto Granular Ferric Hydroxide using a Miniaturized Phosphorus Determination Method.

This paper introduces a procedure to investigate the adsorption of phosphonates onto iron-containing filter materials, particularly granular ferric hydroxide (GFH), with little effort and high reliability. The phosphonate, e.g., nitrilotrimethylphosphonic acid (NTMP), is brought into contact with the GFH in a rotator in a solution buffered by an organic acid (e.g., acetic acid) or Good buffer (e.g., 2-(N-morpholino)ethanesulfonic acid) [MES] and N-cyclohexyl-2-hydroxyl-3-aminopropanesulfonic acid [CAPSO]) in a concentration of 10 mM for a specific time in 50 mL centrifuge tubes. Subsequently, after membrane filtration (0.45 µm pore size), the total phosphorus (total P) concentration is measured using a specifically developed determination method (ISOmini). This method is a modification and simplification of the ISO 6878 method: a 4 mL sample is mixed with H2SO4 and K2S2O8 in a screw cap vial, heated to 148-150 °C for 1 h and then mixed with NaOH, ascorbic acid and acidified molybdate with antimony(III) (final volume of 10 mL) to produce a blue complex. The color intensity, which is linearly proportional to the phosphorus concentration, is measured spectrophotometrically (880 nm). It is demonstrated that the buffer concentration used has no significant effect on the adsorption of phosphonate between pH 4 and 12. The buffers, therefore, do not compete with the phosphonate for adsorption sites. Furthermore, the relatively high concentration of the buffer requires a higher dosage concentration of oxidizing agent (K2S2O8) for digestion than that specified in ISO 6878, which, together with the NaOH dosage, is matched to each buffer. Despite the simplification, the ISOmini method does not lose any of its accuracy compared to the standardized method.

Optimized Procedure for Determining the Adsorption of Phosphonates onto Granular Ferric Hydroxide using a Miniaturized Phosphorus Determination Method

This paper introduces a procedure to investigate the adsorption of phosphonates onto iron-containing filter materials, particularly granular ferric hydroxide (GFH), with little effort and high reliability. The phosphonate, e.g., nitrilotrimethylphosphonic acid (NTMP), is brought into contact with the GFH in a rotator in a solution buffered by an organic acid (e.g., acetic acid) or Good buffer (e.g., 2-(N-morpholino)ethanesulfonic acid) [MES] and N-cyclohexyl-2-hydroxyl-3-aminopropanesulfonic acid [CAPSO]) in a concentration of 10 mM for a specific time in 50 mL centrifuge tubes. Subsequently, after membrane filtration (0.45 µm pore size), the total phosphorus (total P) concentration is measured using a specifically developed determination method (ISOmini). This method is a modification and simplification of the ISO 6878 method: a 4 mL sample is mixed with H2SO4 and K2S2O8 in a screw cap vial, heated to 148-150 °C for 1 h and then mixed with NaOH, ascorbic acid and acidified molybdate with antimony(III) (final volume of 10 mL) to produce a blue complex. The color intensity, which is linearly proportional to the phosphorus concentration, is measured spectrophotometrically (880 nm). It is demonstrated that the buffer concentration used has no significant effect on the adsorption of phosphonate between pH 4 and 12. The buffers, therefore, do not compete with the phosphonate for adsorption sites. Furthermore, the relatively high concentration of the buffer requires a higher dosage concentration of oxidizing agent (K2S2O8) for digestion than that specified in ISO 6878, which, together with the NaOH dosage, is matched to each buffer. Despite the simplification, the ISOmini method does not lose any of its accuracy compared to the standardized method.

Increasing the strength of destroyed wood of wooden architecture monuments by surface modification

The Anglican Church in Arkhangelsk built in 1833 represents a wooden architecture monument. The article describes the strengthening of partially destroyed samples of the Anglican Church wood by surface modification. The first layer of the sandwich coating is nitrilotrimethylphosphonic acid, which forms covalent bonds with the substrate, partially strengthening the wood. The second layer is an epoxy resin solution, which forms covalent bonds with the coating of the first layer, with hydroxyl groups of the first layer involved in the curing of the second layer as well. A two-layer surface coating is formed, while the strength of the wood increases by 2 – 2.5 times, water absorption decreases by 3 times, and mass loss in combustion is no more than 9% according to GOST 27484-87. The monument preservation increases.

Preliminary evaluation of new green antiscalants for reverse osmosis water desalination

Abstract Supplying fresh water has become an important environmental and economic issue. Desalination with reverse osmosis (RO) represents an effective solution to meet the challenges of cleaning brackish water and seawater for drinking and industrial purposes. The principal problem of RO plant operation is the precipitation of low soluble salts (scaling). There are some well-known techniques to reduce scaling; one of the most widespread is antiscalant dosing. In this study, 11 samples of new prototype chemicals based on co-polymers of acrylic and methacrylic acids, polyaspartic acid, maleic anhydride and different cross-linking agents is tested. A wide range of commercial phosphorus-based and green inhibitors were used as reference antiscalants. The testing procedure included circulation experiments on a RO laboratory unit with continuous concentration of feed water – tap water and model solution with elevated hardness. The amount of calcium carbonate accumulated in the membrane module was determined and the inhibitor efficiency was calculated. The best results were obtained for scale inhibitors based on polyaspartic and (poly)acrylic acids. The most promising was the reagent based on a mixture of polyaspartate and nitrilotrimethylphosphonic acid.

Removal of phosphorus from phosphonate-loaded industrial wastewaters via precipitation/flocculation

Phosphonates are to be removed from industrial wastewater before they reach municipal wastewater treatment plants or surface waters. Industrial wastewaters contaminated with the phosphonates 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC), 1-hydroxyethylidene-(1,1-diphosphonic acid) (HEDP), nitrilotrimethylphosphonic acid (NTMP), ethylenediamine tetra(methylene phosphonic acid) (EDTMP) and diethylenetriamine penta(methylene phosphonic acid) (DTPMP) can be subdivided into: (1) mostly clear concentrates with a high water hardness, and (2) organically polluted wastewaters, for instance from the paper and textile industries. Our own flocculation experiments with FeIII and AlIII salts showed that, at a pH of 7.5, the adsorption affinity of polyphosphonates onto iron hydroxides and aluminum hydroxides significantly decreases with an increasing number of C-P bonds (HEDP>NTMP>EDTMP>DTPMP). In comparison to pure water spiked with phosphonates, the total P removal from concentrates occurred at similar and even lower flocculant dosage concentrations (ß=4–8) (ß is the molar ratio of dosed metal concentration to total P concentration in the raw sample). In organically polluted industrial wastewaters, the formation of flocks, and therefore the total P decrease, only occurred after exceeding a certain flocculant concentration, which varied strongly depending on the wastewater type (ß=0.6–86). Below that concentration, the flocculant underwent complexation, and no elimination could be observed. For most of the wastewaters, the required ß values for at least 80% total P decrease were very similar for both FeIII and AlIII. Furthermore, Ca(OH)2 as flocculant turned out to be an effective tool for total P removal and simultaneous softening of calcareous concentrates.

IMPACT OF FORMULA-TECHNOLOGICAL FACTORS ON CONCRETE STRENGTH INDICATORS FOR INJECTING WITH TWO-STAGE EXPANSION

Abstract. Objectives The aim of the study is to clarify the dependence of the cement stone strength on additional porosity that is formed owing both to the cement stone’s development of free deformations and the expansion of the hardening concrete in the second stage as caused by the action of the expanding additive. Method The study is based on the introduction of a sulphoaluminate-type expanding additive in the composition of a binder based on alumina cement, natural gypsum stone and nitrilotrimethylphosphonic acid. Results It is shown that an important role is played in the technology of expanding concrete not only by the degree of expansion of the cement stone, but also by its strength, both during the development of deformations and following stabilisation. Among factors influencing the kinetics of hardening are not only recipe-related (composition and dosage of the additive, mineralogical composition of Portland cement clinker, composition of the concrete, presence of chemical additives), but also technological (fineness of cement grinding, hardening temperature, etc.) that makes the management of the processes of structure formation quite complex. The dependence of the strength of cement stone on the additional porosity formed due to the growth of the cement stone own free deformations and expansion of the hardening concrete in the second stage due to the action of the expanding additive is revealed; dependence of the influence of kinetics of the structure formation regulator - nitrilotrimethylphosphonic acid - on the consistency of the development of the intrinsic free expansion deformations and the formation of the strength of the cement stone in the second stage; the dependence of the strength of the cement stone on the additional porosity formed due to gas evolution and expansion of the mixture in the first stage due to the action of the gas-forming additive; the influence of the constraint of expansion on the formation of the structure of cement stone and its strength; the effect of hardening conditions on the strength characteristics of concrete with a two-stage expansion. Conclusion The process of expansion under the conditions of deformation free development is accompanied by an increase in the porosity of the cement stone of up to 9% and a regular decrease in the strength of the cement stone by compression up to 19.3%. The effect of hardening conditions on the compressive strength of concrete with a two-stage expansion is established: when exposed to air for 28 days at a temperature of 5 oC, the strength decreases to 50% relative to normal conditions, and at a temperature of 35 oС - to 14 %. With water aging the strength is reduced to 33% due to intensive expansion in the second stage. The dependence of the ratio of tensile strength to compressive strength for concretes with a two-stage expansion is specified, taking into account the hardening conditions.

Coordination compounds of oxovanadium(IV) with organophosphonic complexones in aqueous solutions

Complexation in systems containing vanadyl cations and organophosphonic acid complexone anions (POC, Pocj), such as 1-hydroxyethylidenediphosphonic acid (HEIDP, Heidp4−), nitrilotrimethylphosphonic acid (NTP, Ntp6−), and 2-phosphonobutane-1,2,4-tricarbocylic acid (PBTC, Pbtc5−), was studied by absorption spectroscopy and potentiometry. The molar and protonic compositions of the complexonates formed and the regions of their formation and existence were determined. The equilibrium constants of reactions and the stability constants of the complexonates were calculated. Experimental data were processed by the mathematical models that were able of evaluating the possibility of the existence of a wide spectrum of complex species in solution and to select the species sufficient to confirm experimental data.

Speciation in the ternary system Iron(III)-nitrilotrimethylphosphonic acid-1,3-dicarboxypropane-1-iminodiacetic acid

The interaction of iron(III) ions with nitrilotrimethylphosphonic acid and 1,3-dicarboxypro-pane-1-iminodiacetic acid in aqueous solutions has been studied by spectrophotometry. It has been shown that complex formation in the system is complicated by protonation, hydrolysis, and precipitation. Homoligand 1: 1 complexes of different proton composition have been identified. The stability constants of the iron(III) complexonates and their fractional distribution as a function of pH (T = 20 ± 2°C, I = 0.1) have been determined. Conditions that make it possible to prevent the precipitation of iron(III) nitrilotrimethylphosphonates in the presence of 1,3-dicarboxypropane-1-iminodiacetic acid have been selected.

Complexes of nitrilotrimethylphosphonic acid with cobalt, nickel, copper and zinc

Substances of the types MH 4ntmp, Mg 3[M(Hntmp)] 2, M 2H 2ntmp and Mg[M 2(Hntmp)] 2, where M = Co, Ni, Cu, Zn and H 6ntmp = N[CH 2PO(OH) 2] 3 were prepared. The sodium and cesium salts of the [Co(Hntmp)] 3− complexes were also prepared. The IR and electronic spectra and the experimental magnetic susceptibilities indicate that these are high-spin complexes. The coordination surroundings of the central atom consist of a highly distorted octahedron of the ligand oxygen atoms. The nitrogen atom is not coordinated to the central atom.

Chemical mechanism of formation of nitrilotrimethylphosphonic acid

1. When making nitrilotrimethylphosphonic acid by the reaction of formaldehyde and ammonia derivatives with phosphorus trichloride or phosphorus acid in aqueous medium the main product was methylaminodimethylphosphonic acid. 2. This process differed only in rate on using phosphorus trichloride and phosphorus acid and by the formation of different intermediate products when using ammonium chloride or hexamethylenetetramine.