Polyepoxysuccinic Acid Research Articles

Mechanistic study of polyepoxy succinic acid (PESA) as green corrosion inhibitor on carbon steel in aerated NaCl Solution

The inhibition mechanism of mild steel corrosion in aerated aqueous 3% NaCl medium was studied using Polyepoxy succinic acid (PESA) as a green inhibitor. The study utilized electrochemical, thermodynamic, and surface microscopic techniques. Computational methods supported the empirical results of the inhibition mechanism at the molecular level. Results showed inhibition efficiency of PESA exceeding 60% at 2 g/l at 25 °C through the formation of a protection layer on mild steel surface. An addition of 2 mg/l of zinc cations to 2 g/l of PESA at 25 °C enhanced the inhibition efficiency reaching 90%. SEM and AFM scans revealed an efficient coverage of an adsorbed layer on mild steel surface. Quantum chemical, Monte Carlo computation and simulation provided mechanistic insights of the reactivity sites and PESA’s adsorption strength on metal surface.

Mechanism and Optimization of Polyepoxysuccinic Acid in Washing Cd-, Pb-, and Zn-Contaminated Soils

Mechanism and Optimization of Polyepoxysuccinic Acid in Washing Cd-, Pb-, and Zn-Contaminated Soils

Efficiency and comprehensive risk assessment of soil Pb and Cd by washing technique with three biodegradable eluents.

Soil washing with environmentally friendly eluents is a rapid remediation technique for farmland polluted by heavy metals. In this study, polyepoxysuccinic acid (PESA), ethylenediamine tetra (methylene phosphonic acid) sodium (EDTMPS), and phosphonyl carboxylic acid copolymer (POCA) were applied to remedy paddy and arid soils polluted by Pb and Cd. At the same time, ethylenediaminetetraacetic acid (EDTA) was used as a control eluent. PESA showed comparable removal of soil Pb and Cd (over 80.0%) with EDTA, and EDTMPS and POCA removed two heavy metals by 35.2-50.3%. For labile fractions, PESA significantly removed Pb by 93.5-96.7% and Cd by 84.9-90.3% in two soils. EDTMPS and POCA removed Pb by 75.5-85.8% in two soils, while they only removed Cd by 11.7-42.2% in paddy soil, and 76.3-81.7% in arid soil. The risks of total heavy metal concentrations were reduced from the high risk to low risk in paddy soil, and to considerable risk in arid soil, while only dropped to considerable or even had no change by EDTMPS and POCA leaching. The risks of the two soils reduced from high to low or considerable level after PESA washing based on labile fraction change, and to considerable or high level after EDTMPS and POCA leaching, respectively. Therefore, PESA is an ecological benefit eluent for remediating the farmland polluted by heavy metals, and the risk assessment based on labile fraction more easily identifies the dynamic change of heavy metal during the washing process.

Evaluation of Arginine‐Modified Polyepoxysuccinic Acid as Anti‐scaling and Anti‐corrosion Agent

AbstractArginine‐modified polyepoxysuccinic acid (Arg‐PESA) was used as a scale inhibitor to study its anti‐scaling and anti‐corrosion performance. The existence of arginine groups enhances the adsorption and chelation of calcium substances, thus inhibiting the formation of a calcium scale. The effects of temperature, scale inhibitor concentration, pH, and calcium ion concentration on scale inhibition performance were studied. The morphologies and structures of the calcium scale and carbon steel coupons were observed and characterized by spectroscopic and microscopic methods. The interaction between Arg‐PESA and different crystal surfaces of calcium carbonate was simulated by molecular dynamics to elucidate the anti‐scaling mechanism. The addition of Arg‐PESA also significantly enhanced the dispersion of iron oxide.

Utilization of polyepoxysuccinic acid as a green depressant for the flotation separation of smithsonite from calcite

As a green organic acid with biodegradable and low-cost characters, polyepoxysuccinic acid (PESA) was utilized as a depressant to achieve the flotation separation of smithsonite from calcite in this study. Microflotation tests showed that both smithsonite and calcite had good floatability when using sodium oleate (NaOl) as the collector, while calcite was selectively depressed when using PESA as the depressant. The flotation of artificially mixed minerals confirmed that the efficient separation of smithsonite from calcite could be realized in the presence of PESA. A flotation concentrate with 44.56% Zn grade and 81.03% recovery could be obtained from the original feed (26.59% Zn grade) using the reagent scheme of PESA/NaOl. Zeta potential measurement indicated that the addition of PESA might prevent the NaOl adsorption onto a calcite surface rather than a smithsonite surface. X-ray photoelectron spectroscopy (XPS) analysis revealed the strong chemical bonding could only occur between the carboxyl group of PESA and calcium ions at the calcite surface. In contrast, weak interaction occurred between PESA and smithsonite surface, then NaOl was still easily absorbed onto smithsonite surface. These results demonstrated that PESA could be used as a selective depressant for calcite in the smithsonite flotation.

Effect of Acidic Polymers on the Morphology of Laser-Induced Nucleation of Cesium Chloride.

An approach to controlling morphology and size is presented through the combination of laser-induced nucleation and polymer additives. Here, we apply the technique of non-photochemical laser-induced nucleation to irradiate a supersaturated solution (S = 1.15) of cesium chloride (CsCl). The solution immediately responds to laser exposure, and spherical crystallites are produced along the laser pathway. The crystals gradually grow into snowflake-like crystals with different sizes. In this report, two types of acidic polymers including polyepoxysuccinic acid (PESA) and polyaspartic acid (PASA) were individually added in supersaturated CsCl solution to shape its crystalline morphology; we found that a particular property of this control from PESA is uniformity in modification of crystal sizes. Additionally, we observed that both PESA and PASA were able to decrease crystal growth velocity and the quantity of crystals after laser irradiation. With the effect of more than 0.2 wt % PESA in solution, spherical crystallites were initially induced by laser; after that, crystal growth velocities and sizes became slower and smaller with increase in mass fraction of PESA, which led to identical crystal sizes. With the effect of more than 5 wt % PESA, the resulting crystalline morphology obtained by laser was flower-like crystals, whilst cuboid-shaped crystals could be obtained by spontaneous nucleation. Classical nucleation theory, crystal growth rate, and additives as large-size impurities were discussed to analyze the underlying mechanism of the change in morphology.

Effect Analysis of Removing Lead and Arsenic from contaminated soil by Selected Eluents

In order to reduceof the amount of lead and arsenic in contaminated soil, CA(citric acid), PA(polyepoxysuccinic acid), MA(malic acid) and EDTA were used to remove as chemical extractor. The experiments showed that the extraction ability of lead was EDTA>CA>MA>PA, and of arsenic was MA>CA>PA=EDTA. The eluents concentration, reaction period and liquid/solid ratio were the key factor of extraction effect. It was evident that the optimal condition was 0.1 mol/L eluent and 2h of extraction period.

Molecular dynamics simulation and DFT calculation of “green” scale and corrosion inhibitor

The environmental-friendly scale and corrosion inhibitors have been a hot topic in research. Four carboxylic acid type scale and corrosion inhibitors are introduced in this study, including polyaspartic acid (PASP), polyepoxysuccinic acid (PESA), oxidized starch (OS), and carboxymethyl cellulose (CMC). The scale and corrosion inhibition performance of PASP, PESA, OS, and CMC were investigated by molecular dynamics (MD) simulation and density functional theory (DFT) calculation. The interaction between the inhibitor and the surface of CaCO3 (110), CaCO3 (104), CaSO4 (020), and Fe (110) was explored with and without water, respectively. The results indicate that the binding energy of the inhibitor onto the surface of CaCO3 (110), CaCO3 (104), and CaSO4 (020) is as follows: PESA > PASP > OS > CMC. The binding energy onto the Fe (110) surface is: PASP > OS > CMC > PESA. It is worth noting that the influence of water molecules cannot be ignored. Besides, the global reactivity parameters of four inhibitors were also calculated to further explain the corrosion inhibition performance and mechanism, such as EHOMO, ELUMO, ΔE, χ.

Exploration of a novel depressant polyepoxysuccinic acid for the flotation separation of pentlandite from lizardite slimes

Lizardite is representative of a group of serpentine minerals that coexists with nickel sulfide minerals, and the lizardite slime coating that easily forms on surfaces during mineral processing, making it difficult for beneficiation. In this study, a biodegradable polyepoxysuccinic acid (PESA) was introduced as a novel depressant to eliminate the adverse effects of lizardite slimes on pentlandite flotation. The results of microflotation tests and adsorption measurements showed that PESA addition considerably increased the separation efficiency of pentlandite from lizardite slimes, which could be attributed to the improvement of collector adsorption density on the pentlandite surface. Zeta potential measurements and DLVO calculations showed that the lizardite surface charge changed from positive to negative in the presence of PESA, and the resulting electrostatic repulsion caused hetero-dispersion between pentlandite and lizardite particles. Consequently, a collector could adsorb onto the exposed pentlandite surface, restoring the floatability of pentlandite. X-ray photoelectron spectroscopy (XPS) analysis was used to characterize the chemical interactions between PESA and the Mg sites on the lizardite surface. These results demonstrate that PESA can be used as an effective depressant for removing lizardite slimes from the pentlandite surface in a flotation system.

Utilization of polyepoxysuccinic acid as the green selective depressant for the clean flotation of phosphate ores

In flotation, the application of some flotation reagents may cause serious water pollution and damage the ecological environment and human health. Large consumption of flotation reagents also restricts the sustainable production of mines. Therefore, the development and application of environmentally friendly and economical flotation reagents are essential for the sustainable production of phosphate ores and phosphate fertilizer. In this work, a non-nitrogen and phosphorus-free green, economical and environmentally friendly reagent, polyepoxysuccinic acid was used to evaluate its selective inhibition on calcite during apatite flotation. Micro-flotation experiments were used to investigate the floatability of the two minerals. Bench-scale flotation experiments were used to verify the efficiency of industrial application of polyepoxysuccinic acid in the flotation phosphate ores. Depression mechanism of polyepoxysuccinic acid was revealed through zeta potential measurements, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscope. The flotation separation of apatite and calcite can be achieved with polyepoxysuccinic acid using sodium oleate as collector. Bench-scale flotation experiments show that a good flotation index with a P2O5 grade of 32.74% and a recovery of 84.82% can be obtained at a depressant dosage of 80 g/t. Mechanism experiment proved polyepoxysuccinic acid had a stronger adsorption on calcite than apatite. The adsorption of polyepoxysuccinic acid on calcite was mainly chemical adsorption through the chelation of its carboxyl group and calcium atoms. Therefore, this work provides a clean and economic reagent for the sustainable production of phosphate ores and phosphate fertilizer, which is of great significance for the sustainable development of clean mines.

Synergistic inhibition effect and mechanism of polycation and polyanion on colloidal silica

The silica inhibition of Reverse osmosis (RO) membrane can be treated by adding scale inhibitor. The polycation adipic acid/amine-terminated polyethers D230/diethylenetriamine copolymer (AA/AT/DE) was found to be an effective silica scale inhibitor. The drawback of this scale inhibitor is that small amounts of SiO2 -AA/AT/DE white insoluble floc appear in the solution during the inhibition process. In this study, polyepoxysuccinic acid (PESA) was added to solve this problem. The scale inhibition efficiency of different combinations was tested by static screening tests. The content of silicon dioxide was determined by silicomolybdate spectrophotometric method. In a certain dose range (< 50 ppm), the introduction of PESA can improve the inhibition performance of AA/AT/DE, while, it will have a negative impact when the concentration of PESA was increased to 50 ppm. Based on zeta potential and atomic force microscopy (AFM) topographical analyses, the effect of polycation on the formation of silica particles and the mechanism of the synergistic effect of AA/AT/DE and PESA were placed attention on.

Performance of green antiscalants and their mixtures in controlled calcium carbonate precipitation conditions reproducing industrial cooling circuits

Cooling circuits in many industrial sectors are faced with daily issues of scaling. One preventive treatment consists in injecting a polymer additive in the circuit to inhibit precipitation of calcium carbonate. Among the used additives, very few are “green” and the efficiency of new candidates are difficult to test directly in industrial conditions. The present study compared performance between two “green” polymer additives, polyaspartic acid (PASP) and polyepoxysuccinic acid (PESA), versus a traditional gold-standard, homopolymer of acrylic acid (HA) in a laboratory scale set-up designed to be representative of an industrial circuit. Results showed that HA and PASP are both inhibitors of calcium carbonate crystal growth. This inhibition resulted from adsorption of polymer additive molecules on the crystal surface, as confirmed by adsorption measurement. Under the same conditions, PESA additive, showed a high rate of calcium ion complexation and a very low inhibition rate. But, PESA was shown to be a nucleation delayer. Mixing PESA and PASP can gave nucleation retardation of about 19 h, which approximates the 24 h water residence time in industrial cooling circuits, as well as almost 90% calcium carbonate crystal growth inhibition. This synergy offers promising prospects for preventive scaling treatment.

Experimental and Theoretical Studies of Carboxylic Polymers with Low Molecular Weight as Inhibitors for Calcium Carbonate Scale

Poly acrylic acid (PAA) and polyepoxysuccinic acid (PESA) were investigated as scale inhibitors. The static experiments certified that PAA was superior to PESA for the inhibition of calcium carbonate in the low molecular weight range. The X-ray diffraction patterns suggest that the effect of PAA on the calcite (1 0 4) and (1 1 0) crystal plane was more obvious. Scanning electron microscopy was used to study the surface morphology of the depositions, which indicated that the addition of scale inhibitors could disturb the normal growth of CaCO3 scale. The transmittance ratio of ferric oxide demonstrated that PAA had a better dispersion performance than PESA. The molecular dynamics simulation and quantum calculation were selected to theoretically explore the mechanism and structure of scale inhibitors, indicating that the interaction of PAA with (1 0 4) and (1 1 0) calcite crystal surfaces was stronger than PESA. In addition, the results indicated that the PAA with negative charge more easily adsorbed free Ca2+ in the aqueous phase. Based on these observations, PAA exhibited better scale inhibition and dispersion effects than PESA in the case of low molecular weight.

Inhibition, dispersion and corrosion performance of a novel modified polyepoxysuccinic acid

Inhibition, dispersion and corrosion performance of a novel modified polyepoxysuccinic acid

Application and Development of Green Scale Inhibitor: A Mini- Review

Green scale inhibitor has the characteristics of high-efficiency, multifunctional, non-toxic and biodegradable, so it is widely used in water treatment. Some scale inhibitors such as polyaspartic acid type, polyepoxysuccinic acid type and poly Valley are reviewed in this paper. By investigating green scale inhibitors, it is proposed that the complexes of amino acid scale inhibitors and their copolymers should be the focus of future research. The development direction of new green scale inhibitors is pointed out, which provides reference and basis for the research and development of new water treatment scale inhibitors in the future.

The inhibitory effects of four inhibitors on the solution adsorption of CaCO3 on Fe3O4 and Fe2O3 surfaces

This study presents the inhibitory effects of four scale inhibitors, including polyacrylic acid (PAA), hydrolyzed polymaleic anhydride (HPMA), polyepoxysuccinic acid (PESA) and polyaspartic acid (PASP), on the adsorption of CaCO3 on the surfaces of Fe3O4 and Fe2O3. Samples were characterized using SEM and EDS and the average atomic number ratios of Ca/Fe were calculated. Inhibition effects followed the trend: PESA > PAA > PASP > HPMA and PESA > PASP > HPMA > PAA for Fe3O4 and Fe2O3, respectively. Molecular dynamics simulations based on the adsorption model of the scale inhibitor on the surface and calculations of the adsorption energy between the scale inhibitor molecule and the surface revealed that the relatively high scale inhibitory effect is due to low adsorption energy between the inhibitor molecule and the surface. Density Functional Theory (DFT) calculations of the model after adsorption revealed that the relatively low adsorption energy depends on the number of H-O bonds formed as well as those with higher Mulliken population values between the scale inhibitor and the surface.

The inhibition effect mechanisms of four scale inhibitors on the formation and crystal growth of CaCO3 in solution

The experimentation, molecular dynamics simulation and DFT calculation were used to study the inhibition effects of four scale inhibitors, including polyacrylic acid (PAA), hydrolyzed polymaleic anhydride (HPMA), polyepoxysuccinic acid (PESA) and polyaspartic acid (PASP), on formation and crystal growth of CaCO3 in solutions. According to concentrations of Ca2+ in solutions, the sequence of inhibition effects of scale inhibitors on formation of CaCO3 in the solution was PESA > PASP > HPMA > PAA. Characterization of CaCO3 crystals by XRD and a laser particle size analyzer indicated that the sequence of inhibition effects of scale inhibitors on crystal growth of CaCO3 in solutions was PESA > HPMA > PASP > PAA. Interaction energies between the scale inhibitor molecule and Ca2+, and between the scale inhibitor molecule and the CaCO3 (104) surface indicated that the difference of the inhibition effects was derived from the difference in the interaction energy. The results of DFT calculation indicated that the difference between the interaction energies of these inhibitors and Ca2+ was derived from differences of number and the Mulliken population values of the chemical bonds which formed between the inhibitor molecule and Ca2+ and between the inhibitor molecule and the CaCO3 surface.

Experimental and Electrochemical Research of an Efficient Corrosion and Scale Inhibitor

A novel corrosion and scale inhibitor (TPP) containing tobacco stem extract (TSE), polyepoxysuccinic acid (PESA), and polyaspartic acid (PASP) was obtained by the optimal proportion of the orthogonal test. The anticorrosion effect of TPP for carbon steel was researched by static weight-loss method, on-line simulated dynamic test, electrochemical measurement, and scanning electron microscopy (SEM). The results showed that TPP could protect carbon steel efficiently with a maximal corrosion inhibition rate of 85.7% and it was a mixed-type corrosion inhibitor, mainly exhibiting cathode suppression capacity. Simultaneously, the results of calcium carbonate deposition experiment indicated that the scale inhibition rate of TPP was up to 100%.

Inhibition performance and adsorption of polycarboxylic acids in calcite flotation

As a common gangue mineral, the inhibition of calcite is very important to enrich the valuable minerals by flotation. With the increasing complexity of mineral properties and higher requirements for environmental protection, developing a newly eco-friendly depressant for calcite flotation is necessary. In this study, the effects of polyaspartic acid (PASP), polyepoxysuccinic acid (PESA), and hydrolytic polymaleic anhydride (HPMA) on the flotation performance of calcite using sodium oleate as the collector were investigated through flotation experiments. The results showed that all the three depressants exhibited strong inhibition to calcite, and the inhibition capabilities decreased in the order of PASP > HPMA > PESA. The results of zeta potential measurement, contact angle measurement and X-ray photoelectron spectroscopy indicated that the adsorption of sodium oleate on calcite surface was greatly decreased as the addition of the depressant. To investigate the inhibition selectivity, three depressants were used in fluorite flotation, and the results suggested that sodium oleate could still adsorb on fluorite surface in the presence of PASP. The flotation separation of fluorite from calcite could be therefore realized with PASP on the basis of the best selectivity among the three depressants.

Inhibition and biodegradability performance of modified polyepoxysuccinic acid as a scale inhibitor against calcium carbonate

Inhibition and biodegradability performance of modified polyepoxysuccinic acid as a scale inhibitor against calcium carbonate