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Joshua Olusegun Okeniyi - One of the best experts on this subject based on the ideXlab platform.

  • Anticorrosion Behaviour of Rhizophora mangle L. Bark-Extract on Concrete Steel-Rebar in Saline/Marine Simulating-Environment.
    The Scientific World Journal, 2019
    Co-Authors: Joshua Olusegun Okeniyi, Esther T. Akinlabi, Jacob Olumuyiwa Ikotun, Elizabeth Toyin Okeniyi
    Abstract:

    This paper investigates anticorrosion behaviour of the bark-extract from Rhizophora mangle L. on steel-rebar in concrete slabs in 3.5% NaCl medium of immersion (for simulating saline/marine environment). Corrosion-rate, corrosion-current, and corrosion-potential were measured from the NaCl-immersed steel-reinforced concrete cast with admixture of different plant-extract concentrations and from positive control concrete immersed in distilled water. Analyses indicate excellent mathematical-correlation between the corrosion-rate, concentration of the bark-extract admixture, and electrochemical noise-resistance (ratio of the corrosion-potential standard deviation to that of corrosion-current). The 0.4667% Rhizophora mangle L. bark-extract admixture exhibited optimal corrosion-inhibition performance, η = 99.08±0.11% (experimental) or η = 97.89±0.24% (correlation), which outperformed the positive control specimens, experimentally. Both experimental and correlated results followed Langmuir adsorption isotherm which suggests prevalent physisorption mechanism by the plant-extract on the reinforcing-steel corrosion-protection. These findings support Rhizophora mangle L. bark-extract suitability for corrosion-protection of steel-rebar in concrete structure designed for immersion in the saline/marine environmental medium.

  • Biochemical characterization data from Fourier transform infra-red spectroscopy analyses of Rhizophora mangle L. bark-extract
    Chemical Data Collections, 2019
    Co-Authors: Joshua Olusegun Okeniyi, Esther T. Akinlabi, Stephen A. Akinlabi, Elizabeth Toyin Okeniyi
    Abstract:

    Abstract This article presents biochemical characterization data, of organic functional groups and 3-D optimized structures of identified organic chemicals, from the Fourier transform infra-red (FT-IR) spectroscopy analyses of Rhizophora mangle L. bark-extract. Spectral plot from FT-IR spectroscopy instrumentation application to the Rhizophora mangle L. bark-extract, which includes numerical data of adsorbed frequencies for indicating fingerprints/vibration modes of organic functional groups, is supplied in the paper. The obtained spectrum was also rendered to the computer-based Euclidean Search® of the Fluka Library® reference database, for obtaining hit-list of organic chemical compounds constituted in the bark-extract. Adsorbed functional groups from the FT-IR spectroscopy, including N H, C N, C N, O P(=O)(H O) and S-containing ligands, are corroborated by the chemical compounds identified by the computer-based hit-list. These data of biochemical constituent characterizations are useful for gaining insights into the prospects of using bark-extract from Rhizophora mangle L. natural-plant for corrosion-protection of metallic materials in aggressive service-environments.

  • Rhizophora mangle L. LEAF BIOCHEMICAL CHARACTERIZATION: NATURAL-GREEN TOTAL-CORROSION INHIBITION PROSPECT ON CONCRETE STEEL-REINFORCEMENT IN 3.5% NaCl
    Jurnal Teknologi, 2018
    Co-Authors: Joshua Olusegun Okeniyi, Esther T. Akinlabi, Stephen A. Akinlabi, Elizabeth Toyin Okeniyi, Jacob Olumuyiwa Ikotun, Ojewumi Modupe Elizabeth
    Abstract:

    Effective corrosion-protection by plant-extract on metals, in aggressive service-environment, is dependent on the biochemical constituents of which the natural plant is made-up. This paper investigates biochemical characterization of inorganic and organic constituents of Rhizophora mangle L. leaf for gaining insight on its steel-reinforcement corrosion mitigating prospect in NaCl-immersed concretes. For the study, atomic absorption spectroscopy (AAS), Fourier transform infrared spectroscopy (FT-IR) and phytochemical screening analyses were employed. Total-corrosion effect was also studied from steel-reinforced concrete samples, having different concentrations of the leaf-extract as admixture, and which were immersed in 3.5% NaCl (simulating saline/marine environment). Results, by AAS, showed that Rhizophora mangle L. leaf inorganic constituents were highest in iron, Fe = 10,316.17 μg/g and lowest in cadmium, Cd = 6.2019 μg/g but has neither lead (Pb) nor chromium (Cr). Also, organic constituents, by FT-IR, indicated extract from the leaf constitutes aromatic chained compounds rich in π-electrons as well as sulphur, nitrogen and oxygen-bearing ligands to which iron (steel-rebar) exhibits coordinate affinity. Phytochemical characterization showed that the leaf-extract contains alkaloids, tannins, phlobatannins, saponins, steroids and glycosides. Corrosion-inhibiting prospect testing, using the leaf-extract, indicated reduced steel-reinforcement total-corrosion effects that correlated with the extract admixture concentrations employed in the 3.5% NaCl-immersed steel-reinforced concretes.

  • Anticorrosion and Adsorption Mechanism of Rhizophora mangle L. Leaf-Extract on Steel-Reinforcement in 3.5% NaCl-Immersed Concrete
    Proceedings of the 3rd Pan American Materials Congress, 2017
    Co-Authors: Joshua Olusegun Okeniyi, Cleophas Akintoye Loto, Olugbenga Adeshola Omotosho, Abimbola Patricia Idowu Popoola
    Abstract:

    This paper studies anticorrosion and adsorption mechanism of Rhizophora mangle L. leaf-extract on steel-reinforcement in concrete immersed in 3.5% NaCl test-environment. Open circuit potential, macrocell current and corrosion rate measurements were obtained from steel-reinforced concrete samples, into which different concentrations of the leaf-extract was admixed during casting, and which were immersed in the saline/marine simulating-environment. Corrosion noise resistance was modelled as the ratio of standard deviation of the corrosion potential to the standard deviation of the corrosion current. Analyses of these test-results showed that the corrosion rate from linear polarization resistance exhibited very good correlation with the noise resistance model for the leaf-extract concentrations studied. Further analyses identified Rhizophora mangle L. leaf-extract concentration with excellent corrosion inhibition efficiency performance on steel-reinforcement. Also data of anticorrosion performance followed the Langmuir adsorption isotherm model, which indicated physisorption as the prevalent corrosion-protection mechanism by the Rhizophora mangle L. leaf-extract on steel-rebar in concrete immersed in the 3.5% NaCl, simulating saline/marine environment.

  • evaluation and analyses of Rhizophora mangle l leaf extract corrosion mechanism on reinforcing steel in concrete immersed in industrial microbial simulating environment
    Journal of Applied Sciences, 2015
    Co-Authors: Joshua Olusegun Okeniyi, C A Loto, A. P. I. Popoola
    Abstract:

    Test-data from electrochemical monitoring methods were obtained from Rhizophora mangle L. leaf-extract admixed steel-reinforced concretes for detailing mechanism of the extract on steel-rebar corrosion in 0.5 M H2SO4 (simulating industrial/microbial environment). These electrochemical test-measurements, including corrosion potential, corrosion current and corrosion rate, were subjected to the analyses of probability distributions as per ASTM G16-95 R05 through the Kolmogorov-Smirnov goodness-of-fit test-statistics. Results showed that corrosion rate exhibited correlations with function of the natural plant-extract concentration and compact series of the inverse electrochemical noise resistance; the ratio of standard deviations of corrosion potential and corrosion current. Both the experimental and the correlated-prediction model identified Rhizophora mangle L. leaf-extract admixture concentrations that exhibited inhibition efficiency performance of η>70% on steel-rebar corrosion in the acidic test-medium. The adsorption isotherm modelling of the experimental and the predicted electrochemical test-results exhibited good agreements by following the Langmuir and Flory-Huggins isotherm fittings. In addition, the study identified physisorption as the prevalent corrosion-protection mechanism of the steel-rebar by the plant extract through both of the experimental and the correlated-prediction models of adsorption isotherm analyses.

Abimbola Patricia Idowu Popoola - One of the best experts on this subject based on the ideXlab platform.

  • Anticorrosion and Adsorption Mechanism of Rhizophora mangle L. Leaf-Extract on Steel-Reinforcement in 3.5% NaCl-Immersed Concrete
    Proceedings of the 3rd Pan American Materials Congress, 2017
    Co-Authors: Joshua Olusegun Okeniyi, Cleophas Akintoye Loto, Olugbenga Adeshola Omotosho, Abimbola Patricia Idowu Popoola
    Abstract:

    This paper studies anticorrosion and adsorption mechanism of Rhizophora mangle L. leaf-extract on steel-reinforcement in concrete immersed in 3.5% NaCl test-environment. Open circuit potential, macrocell current and corrosion rate measurements were obtained from steel-reinforced concrete samples, into which different concentrations of the leaf-extract was admixed during casting, and which were immersed in the saline/marine simulating-environment. Corrosion noise resistance was modelled as the ratio of standard deviation of the corrosion potential to the standard deviation of the corrosion current. Analyses of these test-results showed that the corrosion rate from linear polarization resistance exhibited very good correlation with the noise resistance model for the leaf-extract concentrations studied. Further analyses identified Rhizophora mangle L. leaf-extract concentration with excellent corrosion inhibition efficiency performance on steel-reinforcement. Also data of anticorrosion performance followed the Langmuir adsorption isotherm model, which indicated physisorption as the prevalent corrosion-protection mechanism by the Rhizophora mangle L. leaf-extract on steel-rebar in concrete immersed in the 3.5% NaCl, simulating saline/marine environment.

  • Performance of Rhizophora mangle L. Leaf-Extract and Sodium Dichromate Synergies on Steel-Reinforcement Corrosion in 0.5 M H 2 SO 4 -Immersed Concrete
    Corrosion, 2015
    Co-Authors: Joshua Olusegun Okeniyi, Cleophas Akintoye Loto, Abimbola Patricia Idowu Popoola, Olugbenga Adeshola Omotosho
    Abstract:

    This paper investigates performance of different synergistic combinations of Rhizophora mangle L leaf-extract and sodium dichromate (Na2Cr2O7) admixtures on the corrosion of steel-reinforcement in 0.5 M H2SO4-immersed concrete. Steel-reinforcement corrosion, in concrete slabs partially-immersed in the microbial/industrial simulating test-environment, were assessed using non-destructive electrochemical measurements of corrosion rate (CR) and open circuit potential (OCP). Probability distribution function (pdf) analyses, as prescribed by ASTM G16-95 R04, of the scatter of corrosion test-data showed that while datasets of OCP distributed like the Normal, the Gumbel and Weibull pdf's, the datasets of CR were best fitted by the Weibull pdf. Results identified 6 g Rhizophora mangle L leaf-extract + 2 g Na2Cr2O7 synergistic admixture with both optimal inhibition efficiency, η = 90.12, and synergistic parameter that indicated excellent synergistic interaction of the plant-extract with Na2Cr2O7 chemical. That this synergistic admixture out-performed the also effective Na2Cr2O7 admixtures in the study suggests suitability of Rhizophora mangle L leaf-extract as eco-friendly replacement of toxic Na2Cr2O7 inhibitor in H2SO4-immersed steel-reinforced concrete. This is potent with the advantage of reducing environmental effect from lower Na2Cr2O7 usage for controlling corrosion in steel-reinforced concretes for the microbial/industrial environment. © 2015 by Nace International.

  • Modelling Rhizophora mangle L Bark-Extract Effects on Concrete Steel-Rebar in 0.5 M H2SO4: Implications on Concentration for Effective Corrosion-Inhibition
    TMS2015 Supplemental Proceedings, 2015
    Co-Authors: Joshua Olusegun Okeniyi, Cleophas Akintoye Loto, Abimbola Patricia Idowu Popoola
    Abstract:

    In this paper, electrochemical test-data were obtained from 0.5 M H2SO4-immersed steel-reinforced concrete admixed with different Rhizophora mangle L bark-extract concentrations and subjected to modelling analyses for studying corrosion-inhibition effectiveness. For this, macrocell current from zero-resistance ammeter and corrosion-rate from linear-polarization resistance instruments were respectively subjected to total-corrosion modelling as per ASTM G109-99a and statistical-distribution modelling as per ASTM G16-95 R04. Further analyses of these modelled test-results showed that the corrosion-rate correlated excellently (R = 95.04%, Nash-Sutcliffe efficiency = 90.33%, p-value = 0.037) with function of the bark-extract concentration and the total-corrosion from the steel-reinforced concrete samples. In agreements, both experimental and correlation fitting models identified 0.167% Rhizophora mangle L bark-extract with good corrosion-inhibition efficiency, η = 73.30% (experimental) or η = 60.81% (correlation prediction). These bare implications on macrocell technique usage for complimenting identification of admixture concentration for effective corrosion-inhibition of concrete steel-rebar in the microbial/industrial simulating-environment studied

  • Corrosion Inhibition of Concrete Steel-Reinforcement in Saline/Marine Simulating-Environment by Rhizophora mangle L.
    Solid State Phenomena, 2015
    Co-Authors: Joshua Olusegun Okeniyi, Cleophas Akintoye Loto, Abimbola Patricia Idowu Popoola
    Abstract:

    Corrosion inhibition of concrete steel-reinforcement in 3.5% NaCl, simulating saline/marine environment, by the leaf extract of Rhizophora mangle L. was studied in this paper. For this, duplicated specimens of steel-reinforced concrete slabs, admixed with different concentrations of the leaf extract, were immersed in the corrosive test-medium. Analyses, as per ASTM G16-95 R04, of the electrochemical test-results identified 0.0833% Rhizophora mangle L., per weight of cement, with optimal inhibition efficiency η = 95.73±0.15%. The study established a decrease in inhibition effectiveness as concentration of Rhizophora mangle L. increases.

  • corrosion inhibition of concrete steel reinforcement in saline marine simulating environment by Rhizophora mangle l
    Solid State Phenomena, 2015
    Co-Authors: Joshua Olusegun Okeniyi, Cleophas Akintoye Loto, Abimbola Patricia Idowu Popoola
    Abstract:

    Corrosion inhibition of concrete steel-reinforcement in 3.5% NaCl, simulating saline/marine environment, by the leaf extract of Rhizophora mangle L. was studied in this paper. For this, duplicated specimens of steel-reinforced concrete slabs, admixed with different concentrations of the leaf extract, were immersed in the corrosive test-medium. Analyses, as per ASTM G16-95 R04, of the electrochemical test-results identified 0.0833% Rhizophora mangle L., per weight of cement, with optimal inhibition efficiency η = 95.73±0.15%. The study established a decrease in inhibition effectiveness as concentration of Rhizophora mangle L. increases.

Hendrikus J. Laanbroek - One of the best experts on this subject based on the ideXlab platform.

Cleophas Akintoye Loto - One of the best experts on this subject based on the ideXlab platform.

  • Anticorrosion and Adsorption Mechanism of Rhizophora mangle L. Leaf-Extract on Steel-Reinforcement in 3.5% NaCl-Immersed Concrete
    Proceedings of the 3rd Pan American Materials Congress, 2017
    Co-Authors: Joshua Olusegun Okeniyi, Cleophas Akintoye Loto, Olugbenga Adeshola Omotosho, Abimbola Patricia Idowu Popoola
    Abstract:

    This paper studies anticorrosion and adsorption mechanism of Rhizophora mangle L. leaf-extract on steel-reinforcement in concrete immersed in 3.5% NaCl test-environment. Open circuit potential, macrocell current and corrosion rate measurements were obtained from steel-reinforced concrete samples, into which different concentrations of the leaf-extract was admixed during casting, and which were immersed in the saline/marine simulating-environment. Corrosion noise resistance was modelled as the ratio of standard deviation of the corrosion potential to the standard deviation of the corrosion current. Analyses of these test-results showed that the corrosion rate from linear polarization resistance exhibited very good correlation with the noise resistance model for the leaf-extract concentrations studied. Further analyses identified Rhizophora mangle L. leaf-extract concentration with excellent corrosion inhibition efficiency performance on steel-reinforcement. Also data of anticorrosion performance followed the Langmuir adsorption isotherm model, which indicated physisorption as the prevalent corrosion-protection mechanism by the Rhizophora mangle L. leaf-extract on steel-rebar in concrete immersed in the 3.5% NaCl, simulating saline/marine environment.

  • Evaluation and Analyses of Rhizophora mangle L. Leaf-Extract Corrosion-Mechanism on Reinforcing Steel in Concrete Immersed in Industrial/Microbial Simulating-Environment
    Journal of Applied Sciences, 2015
    Co-Authors: Joshua Olusegun Okeniyi, Cleophas Akintoye Loto, A. P. I. Popoola
    Abstract:

    Test-data from electrochemical monitoring methods were obtained from Rhizophora mangle L. leaf-extract admixed steel-reinforced concretes for detailing mechanism of the extract on steel-rebar corrosion in 0.5 M H2SO4 (simulating industrial/microbial environment). These electrochemical test-measurements, including corrosion potential, corrosion current and corrosion rate, were subjected to the analyses of probability distributions as per ASTM G16-95 R05 through the Kolmogorov-Smirnov goodness-of-fit test-statistics. Results showed that corrosion rate exhibited correlations with function of the natural plant-extract concentration and compact series of the inverse electrochemical noise resistance; the ratio of standard deviations of corrosion potential and corrosion current. Both the experimental and the correlated-prediction model identified Rhizophora mangle L. leaf-extract admixture concentrations that exhibited inhibition efficiency performance of η>70% on steel-rebar corrosion in the acidic test-medium. The adsorption isotherm modelling of the experimental and the predicted electrochemical test-results exhibited good agreements by following the Langmuir and Flory-Huggins isotherm fittings. In addition, the study identified physisorption as the prevalent corrosion-protection mechanism of the steel-rebar by the plant extract through both of the experimental and the correlated-prediction models of adsorption isotherm analyses.

  • Performance of Rhizophora mangle L. Leaf-Extract and Sodium Dichromate Synergies on Steel-Reinforcement Corrosion in 0.5 M H 2 SO 4 -Immersed Concrete
    Corrosion, 2015
    Co-Authors: Joshua Olusegun Okeniyi, Cleophas Akintoye Loto, Abimbola Patricia Idowu Popoola, Olugbenga Adeshola Omotosho
    Abstract:

    This paper investigates performance of different synergistic combinations of Rhizophora mangle L leaf-extract and sodium dichromate (Na2Cr2O7) admixtures on the corrosion of steel-reinforcement in 0.5 M H2SO4-immersed concrete. Steel-reinforcement corrosion, in concrete slabs partially-immersed in the microbial/industrial simulating test-environment, were assessed using non-destructive electrochemical measurements of corrosion rate (CR) and open circuit potential (OCP). Probability distribution function (pdf) analyses, as prescribed by ASTM G16-95 R04, of the scatter of corrosion test-data showed that while datasets of OCP distributed like the Normal, the Gumbel and Weibull pdf's, the datasets of CR were best fitted by the Weibull pdf. Results identified 6 g Rhizophora mangle L leaf-extract + 2 g Na2Cr2O7 synergistic admixture with both optimal inhibition efficiency, η = 90.12, and synergistic parameter that indicated excellent synergistic interaction of the plant-extract with Na2Cr2O7 chemical. That this synergistic admixture out-performed the also effective Na2Cr2O7 admixtures in the study suggests suitability of Rhizophora mangle L leaf-extract as eco-friendly replacement of toxic Na2Cr2O7 inhibitor in H2SO4-immersed steel-reinforced concrete. This is potent with the advantage of reducing environmental effect from lower Na2Cr2O7 usage for controlling corrosion in steel-reinforced concretes for the microbial/industrial environment. © 2015 by Nace International.

  • Modelling Rhizophora mangle L Bark-Extract Effects on Concrete Steel-Rebar in 0.5 M H2SO4: Implications on Concentration for Effective Corrosion-Inhibition
    TMS2015 Supplemental Proceedings, 2015
    Co-Authors: Joshua Olusegun Okeniyi, Cleophas Akintoye Loto, Abimbola Patricia Idowu Popoola
    Abstract:

    In this paper, electrochemical test-data were obtained from 0.5 M H2SO4-immersed steel-reinforced concrete admixed with different Rhizophora mangle L bark-extract concentrations and subjected to modelling analyses for studying corrosion-inhibition effectiveness. For this, macrocell current from zero-resistance ammeter and corrosion-rate from linear-polarization resistance instruments were respectively subjected to total-corrosion modelling as per ASTM G109-99a and statistical-distribution modelling as per ASTM G16-95 R04. Further analyses of these modelled test-results showed that the corrosion-rate correlated excellently (R = 95.04%, Nash-Sutcliffe efficiency = 90.33%, p-value = 0.037) with function of the bark-extract concentration and the total-corrosion from the steel-reinforced concrete samples. In agreements, both experimental and correlation fitting models identified 0.167% Rhizophora mangle L bark-extract with good corrosion-inhibition efficiency, η = 73.30% (experimental) or η = 60.81% (correlation prediction). These bare implications on macrocell technique usage for complimenting identification of admixture concentration for effective corrosion-inhibition of concrete steel-rebar in the microbial/industrial simulating-environment studied

  • Corrosion Inhibition of Concrete Steel-Reinforcement in Saline/Marine Simulating-Environment by Rhizophora mangle L.
    Solid State Phenomena, 2015
    Co-Authors: Joshua Olusegun Okeniyi, Cleophas Akintoye Loto, Abimbola Patricia Idowu Popoola
    Abstract:

    Corrosion inhibition of concrete steel-reinforcement in 3.5% NaCl, simulating saline/marine environment, by the leaf extract of Rhizophora mangle L. was studied in this paper. For this, duplicated specimens of steel-reinforced concrete slabs, admixed with different concentrations of the leaf extract, were immersed in the corrosive test-medium. Analyses, as per ASTM G16-95 R04, of the electrochemical test-results identified 0.0833% Rhizophora mangle L., per weight of cement, with optimal inhibition efficiency η = 95.73±0.15%. The study established a decrease in inhibition effectiveness as concentration of Rhizophora mangle L. increases.

Dennis F. Whigham - One of the best experts on this subject based on the ideXlab platform.