Different Concentrations Of Cl Research Articles

Investigation of the Impact of Chloride Contamination on Degradation in PEM Water Electrolyzer Cells

Polymer electrolyte membrane water electrolysis (PEMWE) is a promising technology for hydrogen production from renewable energy sources. However, current systems require ultra-pure water (>18 MΩ*cm) and fail in the presence of impurities like dissolved ions or chemical contaminants [1,2]. Due to the cost of purification and local scarcity of groundwater, there is a rising interest in creating electrolyzers that can function using water of inferior quality [3]. Additionally, feedwater used in offshore applications that is generated by the desalination of seawater still contains low amounts of ionic contaminants [4].Among the most detrimental impurities responsible for performance loss in PEMWE, Cl− is present in high concentrations in both, sea- and potable water [3]. Cl− can reduce the efficiency of the electrolysis process by accelerating component degradation and lower the purity of the produced hydrogen. A competing reaction between the oxygen evolution reaction (OER) and the chlorine evolution reaction (CER) results in the formation of gaseous chlorine that lowers the quality of the produced hydrogen gas. Additionally, Cl− blocking layers can form on the catalyst surfaces which result in a reduced electrochemical surface area. For PEM fuel cells, a technology facing related problems, Cl− adsorption has also been reported to accelerate the formation of hydrogen peroxide [5], promoting chemical degradation of the PFSA-based membrane.The scope of this work is to quantify the reduction of efficiency based on different Cl− concentrations in the feedwater of a PEMWE cell. Therefore, a single cell PEMWE with commercial catalyst coated membranes (CCMs) is exposed to different concentrations of Cl−. The PEMWE single cell is operated up to 100 h and investigated by various characterization techniques, including in-situ and ex-situ cell tests. Electrochemical performance characterization by means of polarization behaviour and impedance spectroscopy is carried out throughout a range of currents (0.01 A cm− 2 to 3.0 A cm− 2) at 60°C. Furthermore, the fluoride emission rate (FER) is monitored during the experiments and optical investigation of the CCMs is carried out after the tests. Based on this complementary investigation, a deeper insight into degradation phenomena associated with Cl− contamination in PEMWE cells is presented. Feng, Q.; Yuan, X.; Liu, G.; Wei, B.; Zhang, Z.; Li, H.; Wang, H. A Review of Proton Exchange Membrane Water Electrolysis on Degradation Mechanisms and Mitigation Strategies. Journal of Power Sources 2017, 366, 33–55, doi:10.1016/j.jpowsour.2017.09.006.Kuhnert, E.; Hacker, V.; Bodner, M. A Review of Accelerated Stress Tests for Enhancing MEA Durability in PEM Water Electrolysis Cells. International Journal of Energy Research 2023, 2023, 1–23, doi:10.1155/2023/3183108.Becker, H.; Murawski, J.; Shinde, D.V.; Stephens, I.E.L.; Hinds, G.; Smith, G. Impact of Impurities on Water Electrolysis: A Review. Sustainable Energy Fuels 2023, 7, 1565–1603, doi:10.1039/D2SE01517J.Bacquart, T.; Moore, N.; Wilmot, R.; Bartlett, S.; Morris, A.S.O.; Olden, J.; Becker, H.; Aarhaug, T.A.; Germe, S.; Riot, P.; et al. Hydrogen for Maritime Application—Quality of Hydrogen Generated Onboard Ship by Electrolysis of Purified Seawater. Processes 2021, 9, 1252, doi:10.3390/pr9071252.Katsounaros, I.; Meier, J.C.; Mayrhofer, K.J.J. The Impact of Chloride Ions and the Catalyst Loading on the Reduction of H2O2 on High-Surface-Area Platinum Catalysts. Electrochimica Acta 2013, 110, 790–795, doi:10.1016/j.electacta.2013.03.156.

Understanding the interaction mechanism of chloride ions and carbon dioxide towards corrosion of 3Cr steel

The investigation focused on elucidating the corrosion mechanism and evolution of corrosion products for 3Cr steel after an exposure to CO2-saturated solutions containing different concentrations of Cl− at 80 and 150 °C. The results show an interaction between dissolved CO2 and Cl− toward corrosion behavior of 3Cr steel. Apart from a competitive relationship between the concentrations of two corrosive species, the evolution of inner and outer films at different temperatures under the interaction between dissolved CO2 and Cl− is a decisive factor in the whole corrosion process, causing a trend of a first increase and then a decrease with increasing Cl− concentration. In addition, the destruction of inner Cr-enriched films after the addition of excessive Cl− conversely reduces the corrosion rates of 3Cr steel, which is mainly due to the formation of FeCO3 crystals instead of Cr(OH)3 in an initial stage of corrosion.

Cu-doped CoOOH activates peroxymonosulfate to generate high-valent cobalt-oxo species to degrade organic pollutants in saline environments

A Cu doped CoOOH-activated peroxymonosulfate (CoCu10/PMS) process was developed to enable the generation of Co(IV)=O for efficient oxidation of pollutants in saline water. The formation of Co(IV)=O was demonstrated through phenylmethyl sulfoxide (PMSO) probe and 18O-isotope-labeling tests. CoCu10 was synthesized using a simple and scalable co-precipitation method, enabling efficient synthesis at laboratory scale for large quantities (gram level). Cu doping increased the surface hydroxyl density of CoOOH, thereby improving its activation performance. Coordinating with PMS through surface hydroxyls, CoCu10 formed catalyst-PMS complexes, then donated electrons to induce heterolytic cleavage of O–O bonds in complexes, resulting in the formation of Co(IV)=O. At a concentration of 0.2 g/L catalyst and 0.2 mM PMS, 97.7% of tetracycline was degraded within 10 min. CoCu10 maintained stable performance over eight cycles. Thanks to Co(IV)=O, the CoCu10/PMS system efficiently operates under different concentrations of Cl−, HCO3−, NO3−, SO42−, H2PO4− and mixed salt.

Application of FeS-activated persulfate oxidation system for the degradation of tetracycline in aqueous solution.

Tetracycline (TC), an antibiotic used to treat bacterial infectious diseases, is easily transferred to environmental matrixes and then sparks environmental concerns. In this study, TC was selected as a target pollutant to investigate the degradation performance of persulfate (PS) based advanced oxidation processes (AOPs) using FeS as the activator (FeS/PS). The results showed that with optimal PS and FeS concentrations of 1mM and a pseudo-second-order rate constant (k2) of 3.45 L mmol-1min-1, 91.39% of TC, was effectively removed within 60min. From the perspective of degradation rate, apart from CO32-, TC decompositions by FeS/PS were hardly disturbed by the coexistence of different concentrations of Cl-, NO3-, SO42-, and humin acid. The degradation of TC under the O2 bubbling, N2 bubbling, and light-proof conditions also had limited effects on these AOPs. In addition, FeS exhibited excellent stability and recyclability when used as a PS activator for TC removal. The PS activated by old FeS and used FeS showed nearly identical performances on TC removal compared with the fresh FeS. It is suggested that homogeneous and heterogeneous reactions are jointly responsible for TC oxidation by FeS/PS. With the contributions of the generated, highly reactive SO4-•, and, in particular, •OH, TC enabled the mineralization of inorganic products eventually. Therefore, FeS/PS is highly recommended as an alternative AOPs in the future for TC-contaminated wastewater purification.

Concentration-dependent chloride effect on radical distribution and micropollutant degradation in the sulfate radical-based AOPs

This study quantitatively evaluated the effect of chloride (Cl−) on the radical distribution and micropollutant degradation in the UV/peroxydisulfate AOP using both experimental and modeling approaches. Results showed that SO4•− was significantly scavenged by Cl− at environmentally relevant concentrations (1–5000 mg/L). With increasing Cl− concentrations from 1 to 5000 mg/L, Cl− transformed SO4•− to HO• and then to Cl2•−. The critical role of Cl2•− as a precursor of HO• in the radical transformation was highlighted. The inhibitory effects of bicarbonate and dissolved organic matter (DOM) on micropollutant degradation was more significant in the presence of Cl− than that in the absence of Cl−, mainly due to the consumption of Cl2•− by bicarbonate and DOM. Using the model-predicted radical concentrations in the UV/peroxydisulfate process in the presence of different concentrations of Cl−, the degradation rate constants of 34 micropollutants and the contributions of each radical to the degradation were predicted and compared. The findings improved the fundamental understanding of the Cl− effect on radical transformation and micropollutant degradation in the SO4•−-based AOPs. The model enables to foresee whether a SO4•−-based AOP is effective for the degradation of a certain micropollutant in the water with known concentrations of Cl−.

Influence of Chloride Ions on Electrochemical Corrosion Behavior of Dual-Phase Steel over Conventional Rebar in Pore Solution

Reinforced steel bars (rebar) are extensively used in construction, and the main challenge is in minimizing corrosion due to oxide or passive layer breakdown. In contrast, dual-phase (DP) steel has good corrosion resistance. This study investigated the effect of Cl− ions on the electrochemical corrosion behavior of DP rebar and conventional rebar. Corrosion behavior studies and electrochemical measurements were conducted on DP rebar and conventional rebar in simulated concrete pore solution with different concentrations of Cl− ions. Microstructure analysis, surface morphology analysis, and corroded surface characterization were performed using optical microscopy, field emission scanning electron microscopy, and Raman spectroscopy, respectively. Potentiodynamic polarization and electrochemical impedance spectroscopy measurements revealed that DP rebar has good passivity, leading to better corrosion resistance and greater strength compared to ordinary rebar. In addition, DP rebar showed better passivity behavior compared to conventional rebar in alkaline solution. Therefore, the presence of a dual phase (ferrite and martensite) in reinforced concrete structured steel induces good corrosion resistance.

Genome-wide identification and expression analysis of the CLC superfamily genes in tea plants (Camellia sinensis).

The voltage-gated chloride channel (CLC) superfamily is one of the most important anion channels that is widely distributed in bacteria and plants. CLC is involved in transporting various anions such as chloride (Cl-) and fluoride (F-) in and out of cells. Although Camellia sinensis is a hyper-accumulated F plant, there is no studies on the CLC gene superfamily in the tea plant. Here, 8 CLC genes were identified from C. sinensis and they were named CsCLC1-8. The structure of CsCLC genes and the proteins were not conserved; the number of exons varied from 3 to 24, and the number of transmembrane domains contained 2 to 10. Furthermore, phylogenetic analysis revealed that CsCLC4-8 in subclass I contained the typical conserved domains GxGIPE (I), GKxGPxxH (II) and PxxGxLF (III), and CsCLC1-3 in subclass II did not contain any of the three conserved residues. We measured the expression levels of CsCLCs in roots, stems and leaves to assess the responses to different concentrations of Cl- and F-. The result indicated that CsCLCs participated in subfunctionalization in response to Cl- and F-, and CsCLC1-3 was more sensitive to F- treatments than CsCLC4-8, CsCLC6 and CsCLC7 may participate in absorption and long-distance transport of Cl-.

Cupric and Chloride Ions: Leaching of Chalcopyrite Concentrate with Low Chloride Concentration Media

In this paper, the effect of the cupric and chloride ions concentrations on copper dissolution from chalcopyrite concentrate was studied in acidified media. Variables included three different concentrations of Cu2+ (0.5, 1.5, and 2.5 g L−1), four different concentrations of Cl− (0, 5, 7, and 10 g L−1), two different pH values of 1 and 2, and a constant temperature of 60 °C. Results indicated that addition of Cl− to the system improves copper extractions, especially at higher concentrations of Cu2+. Initial copper concentrations in the leaching solution did not significantly affect the copper extraction when Cl− was not present. Better copper extractions were obtained at pH 1 as compared with pH 2. As the Cu2+ and Cl− concentrations were increased, higher values of redox potential were obtained. According to the formation constants of the chloro-complexes, the predominant species in the Cu2+/Cl− system in the studied interval were CuCl+ and Cu2+. Using a model of copper speciation in the experimental range predicted for a single copper concentration with increasing Cl− concentration, the Cu2+ concentration decreased significantly while the concentration of the chloro-complex species CuCl+ increased. In the leached residue, evidence of sulfur formation was found using SEM and corroborated by XRD analysis. When chloride is present in the medium, the amounts of copper and iron in the residue decrease, confirming a positive effect of chloride on the extraction of copper from concentrate for the studied conditions.

Experimental Study on the Corrosion of Buried Pipeline in Coastal Area Under the Interference of Stray Current

To explore the effect of stray current and the concentration of Cl− on corrosion of buried pipeline in coastal area, in this paper, indoor electrochemical experiments were used to change the voltage of AC interference. The electrochemical parameters such as zero current potential error, Tafel constant and corrosion current density error of the polarization curves obtained in three different concentrations of Cl− solutions without alternating current interference and with different intensities of alternating current interference were compared and measured. The results showed that the corrosion potential of the sample was shifted negatively. When the interference ratio of the fixed voltage was not disturbed, the corrosion current increased, and the corrosion process changed from cathode reaction control to hybrid control. AC stray current could aggravate the corrosion process of Q235 steel. In the presence of AC stray current, with the increase of applied AC voltage, the corrosion potential of Q235 steel moved negatively, the corrosion current density increased and the corrosion rate accelerated. The concentration of Cl− had a great influence on the reaction rate, and the higher the voltage, the more obvious the effect. This is of great significance for effectively predicting the life of buried pipelines, improving the reliability of buried pipelines during service and protecting the safety of existing pipeline facilities.

Pitting corrosion and effect ofEuphorbia echinusextract on the corrosion behavior of AISI 321 stainless steel in chlorinated acid

AbstractStainless steel (SS) is a very corrosion-resistant alloy used in different industrial plants because of its chemical and mechanical properties. However, the high chloride concentration in sulfuric acid (H2SO4) may promote both general corrosion and pitting corrosion. The pitting corrosion susceptibility in SS in chlorinated H2SO4and the effect ofEuphorbia echinusextract (EEE) on both general corrosion and pitting corrosion have been studied using potentiodynamic polarization, electrochemical impedance spectroscopy, chronoamperometry, cyclic voltammetry, and scanning electron microscopy (SEM). The pitting potential has been found to shift slightly in the presence of chloride ions (Cl−) in H2SO4. Also, pitting corrosion initiation has been demonstrated in the recorded chronoamperograms as a linear straight line having a positive slope. EEE has reduced the general corrosion and the inhibitor adsorption was found to follow the Langmuir isotherm. SEM micrographs showed that the tested inhibitor has efficiently acted on pitting corrosion for different concentrations of Cl−. Also, the kinetic findings were in good agreement with the surface analysis data. Fourier transform infrared spectroscopy and ultraviolet-visible absorption spectrophotometric measurements provided more insights on the interaction between the chemical functional groups of the inhibitor and the SS surface.

Metastable Pitting on 304 Stainless Steel in Cement Extract Solution with Different Concentration of Cl-

Metastable Pitting on 304 Stainless Steel in Cement Extract Solution with Different Concentration of Cl-

Effects of Chloride Ions on Dissolution, ROS Generation, and Toxicity of Silver Nanoparticles under UV Irradiation.

This work investigates the effect of chloride ion (Cl-) on dissolution, reactive oxygen species (ROS) generation, and toxicity of citrate-coated silver nanoparticles (AgNPs) under UV irradiation. The dissolution rate was decreased by 0.01 M Cl- due to AgCl passivation on the AgNP surface. By contrast, high concentrations of Cl- (0.1 or 0.5 M) promoted dissolution due to the formation of soluble Ag-Cl complexes (AgCl x1- x). The generation of O2•- in the AgNPs/Cl-/UV system was promoted by 0.01 M Cl-, whereas it was retarded by 0.1 or 0.5 M Cl-, which was probably because the aggregation of AgNPs at high ionic strength reduced the nanoparticles' surface areas for radical formation. Additionally, Cl- contributed to •OH generation in the AgNPs/Cl-/UV system, in which the produced •OH concentrations increased with increasing Cl- concentrations. The reduction reaction between silver ions and O2•- resulted in lower dissolution rates of AgNPs/Cl- mixtures under UV irradiation than those in the dark. The phototoxicity of AgNPs toward E. coli with different concentrations of Cl- followed the order of 0.5 M > 0 M > 0.1 M > 0.01 M. Both ROS and dissolved Ag played significant role in the phototoxicity of AgNPs. This work demonstrates the potential importance of anions in the fate and biological impact of AgNPs.

Simple and selective paper-based colorimetric sensor for determination of chloride ion in environmental samples using label-free silver nanoprisms

Simple and selective paper-based colorimetric sensors using silver nanoprism (AgNPrs) were conveniently fabricated and developed for the determination of chloride ions (Cl−) contaminated in the environment. Samples containing different concentrations of Cl− were analyzed. The analysis is based on the oxidative etching of the AgNPrs into smaller silver nanospheres (AgNPss) by Cl−. In the presence of Cl−, the distinctive color change of the AgNPrs from dark-violet to red was rapidly visualized by the naked eye in 5min without the requirement of surface modification. For quantitative measurement using image processing, a good linear relationship (R2 = 0.996) between logarithmic of Cl− concentration and the average mean color intensity was obtained in the range of 10–1000mgL−1 with a detection limit of 1.3mgL−1. The developed sensors were investigated for precision, accuracy, and sensitivity and validated by the classical method. Statistical analysis proved that the developed sensors were precise, sensitive and accurate and can be used effectively for the analysis of Cl− in natural waters.

Corrosion behavior of carbon steel in chloride contaminated simulated concrete pore solution with carboxylate of benzoic acid and dimethylethanolamine

PurposeThe purpose of this study is to investigate the inhibition efficiency and mechanism of a specific carboxylate corrosion inhibitor which consists of benzoic acid and dimethylethanolamine on steel surface.Design/methodology/approachThe performance of carbon steel influenced by this organic inhibitor under different concentration of Cl− and immersion time was studied by linear polarization resistance and electrochemical impedance spectroscopy in a simulated concrete pore (SCP) solution. The surface morphology and composition of steel was also analyzed by optical microscopy, SEM and EDS to investigate the effect of inhibitor on the pattern of the steel surface after long-term immersion.FindingsCarboxylate of benzoic acid and dimethylethanolamine can increase the chloride threshold level and decrease the corrosion area of carbon steel in SCP solution with 0.6 mol/L Cl− even after 120 days exposure. The inhibition mechanism of inhibitor lies in quick adsorption and buffering effect at initial time then formed deposited layer on steel surface after long-term immersion in chloride-rich environment.Originality/valueIt demonstrated that the carboxylate corrosion inhibitor not only can improve the chloride threshold level for carbon steel but also effectively decrease the corrosion rate even in chloride-rich SCP solution after long-term immersion, which is different form the conventional amino alcohol.

Effect of gelatine and 5-methyl-1H-benzotriazole on corrosion behaviour of copper in sulphuric acid containing Cl− ions

Copper corrosion behaviour in the presence of binary system containing 5-methyl-1H-benzotriazole and gelatine as well as 1H-benzotriazole and gelatine in 0.01 mol dm−3 H2SO4 with the addition of different concentration of Cl− ions was investigated in this study. The corrosion inhibition effect of these compounds was examined by electrochemical techniques (open circuit potential, potentiodynamic polarization and cyclic voltammetry measurements) and weight loss measurements. The surface analysis by scanning electron microscopy with energy X-ray spectroscopy was also performed to assess the morphology of untreated and treated surface of copper coupons. According to the potentiodynamic polarization results, these inhibitors showed good performance in the presence of Cl− ions and they act as mixed-type inhibitors. The inhibition efficiency of binary system is over 90% indicating that these compounds provide good copper protection in sulphate-chloride solutions. The results obtained from weight loss measurements are in good agreement with the results obtained by electrochemical measurements.

Corrosion resistances of passive films on low‐Cr steel and carbon steel in simulated concrete pore solution

AbstractThe passive ranges of carbon steel rebar and 3Cr steel rebar in saturated Ca(OH)2‐simulated concrete pore solution with pH 12.6 were determined by means of cyclic voltammetry and potentiodynamic polarization curves. Chronopotentiometry was used to obtain steady‐state conditions for the formation of passive films on rebar samples at different anodic potentials. Electrochemical impedance spectroscopy, Mott–Schottky and X‐ray photoelectron spectrometer curves were employed to compare the formed passive films at different potentials. Additionally, cyclic polarization curves were used to compare the corrosion resistances of formed passive films on the two rebars in saturated Ca(OH)2‐simulated concrete pore solution with different concentration of Cl−. The results show that the passive ranges of the two rebars are all between −0.15 and +0.6 V, and more stable passive films can be formed on both rebars at the anodic potential of +0.3 V. In the absence of Cl−, the stability and corrosion resistance of the passive film formed on the 3Cr rebar are better than those of CS rebar. The passive film of 3Cr steel has the relatively better pitting corrosion resistance than carbon steel in saturated Ca(OH)2‐simulated concrete pore solution that contains different concentration of Cl−. Copyright © 2016 John Wiley & Sons, Ltd.

Determination of the Optimal Culture Medium and Salts for Bioassays with Neotropical Halophilic Cladocerans

The neotropical halophilic cladocerans Daphnia menucoensis and Moina eugeniae are common in shallow lakes of semi-arid central and northern Patagonia in Argentina. In the present study, we determined the tolerance of neonates of both species to salinity and different concentrations of Cl- and SO42-. However, the responses differed according to the demineralized water or groundwater employed to dissolve the salts. On the other hand, survival was lower when using analytical grade reagents instead of natural salts. As bioassays should be developed to determine the chronic physiological responses of both species, the objectives of this study were to compare three culture media and test the hypothesis that natural salts dissolved in aquifer water is the optimal combination for breeding. Acute bioassays were conducted with neonates of both species. To compare the media, NaCl solutions (5, 10, 15, 20 and 25 g.L-1) were prepared using demineralized water, aquifer water and EPA medium. For the second objective, solutions of equal concentrations were prepared with salts obtained from the natural environment, previously sterilized, and dissolved in phreatic water. Survival was higher in the aquifer water, whose chemical composition was relatively more representative of the lakes inhabited by both species. It was almost complete at 20 and 15 g.L-1 for D. menucoensis and M. eugeniae, respectively. Lower survival of D. menucoensis was found in EPA medium, although it was developed for breeding other species of Daphnia. In the second series of bioassays, survival was almost complete until 20 g.L-1 (D. menucoensis) and 25 g.L-1 (M. eugeniae). The combination natural salts/aquifer water was adequate to assess the tolerance of both cladocerans. However, the former was more important, since the results were consistent with previous studies when these salts were dissolved in demineralized water. In addition, survival was much higher than when we used salts of analytical grade.

Effect of chromium on the electrochemical properties of iron aluminide intermetallics

The effect of chromium content on the electrochemical properties of Fe3Al intermetallics is examined. The susceptibility of alloys to pitting and crevice corrosion in solutions with different concentrations of Cl− ions was studied with the aid of cyclic polarization and galvanostatic methods. The form of the pits, and their concentration on different crystal orientations, was evaluated with the Scanning Electron Microscopy (SEM) and Electron Backscatter Diffraction (EBSD) techniques. Additionally, Electrochemical Impedance Spectroscopy (EIS) and the Mott–Schottky (MS) methods were used to characterize the passive film. The results show the beneficial effect of Cr for corrosion and hydrogen embrittlement resistance.

Preparation, characterization, and applicability of novel calix[4]arene‐based cellulose acetate membranes in gas permeation

ABSTRACTCellulose acetate (CA) is well known glassy polymer used in the fabrication of gas‐separation membranes. In this study, 5,11,17,23‐tetrakis(N‐morpholinomethyl)‐25,26,27,28‐tetrahydroxycalix[4]arene (CL) was blended with CA to study the gas‐permeation behavior for CO2, N2, and CH4 gases. We prepared the pure CA and CA/CL blended membranes by following a diffusion‐induced phase‐separation method. Three different concentrations of CL (3, 10, and 30 wt %) were selected for membrane preparation. The CA/CL blended membranes were then characterized via Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), and X‐ray diffraction analysis. The homogeneous blending of CL and CA was confirmed in the CA/CL blended membranes by both SEM and AFM analysis. In addition to this, the surface roughness of the CA/CL blended membranes also increased with increasing CL concentration. FTIR analysis described the structural modification in the CA polymer after it was blended with CL too. Furthermore, CL improved the tensile strength of the CA membrane appreciably from 0.160 to 1.28 MPa, but this trend was not linear with the increase in the CL concentration. CO2, CH4, and N2 gases were used for gas‐permeation experiments at 4 bars. With the permeation experiments, we concluded that permeability of N2 was higher in comparison to those of CO2 and CH4 through the CA/CL blended membranes. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 39985.

Electrochemical Corrosion Behavior of Ultra-Supercritical Unit Waterwall Tube Material in Simulated Solution of Oxygenated Treatment at Room Temperature

The electrochemical corrosion behavior of ultra-supercritical unit waterwall tube material in simulated solution of oxygenated treatment (OT) with different concentration of Cl- and SO42- at room temperature was investigated by electrochemical impedance spectroscopy and Tafel slopes. The results showed that the polarization resistance Rp values decreased and corrosion current density (icorr) increased with increasing Cl-/ SO42- concentration in solution. Corrosion potentials (Ecorr) decreased with increasing Cl-/ SO42- concentration in solution.