Loto Roland Tolulope is a Professor at the Department of Mechanical Engineering, Covenant University, Ogun State, Nigeria. He is the principal investigator of the corrosion and materials research cluster. Roland has over one hundred and fifty five (155) research publications including reviews in top international journals and has consistently served as reviewer in respectable journals due to his in-depth knowledge and technical expertise. He has a lot of experience in research experimentation basically aimed at proffering solutions to the current depreciating effect of metallic degradation and failure in various engineering applications. He is a registered member of the Council for the Regulation of Engineering in Nigeria, South African Institute of Mining and Metallurgy and the Corrosion Institute of Southern Africa. Phone: +2348084283392
Applications of harmless fluid derivative for the sustenance of carbon steel in corrosive environ... more Applications of harmless fluid derivative for the sustenance of carbon steel in corrosive environments are more appropriate for environmental sustainability and safety of personnel. Admixture of grapefruit and lemongrass distillates was assessed for their protective performance on plain carbon steel within 0.5 M of H2SO4 and HCl solution through weight loss analysis and optical macroscopy studies. Results shows the plant extracts effectively stifled corrosion in both acids with inhibition value range (lowest to highest) of 98.65%-99.5% in H2SO4 solution and 96.31%- 98.39% in HCl. PCS in H2SO4 and HCl electrolyte at 0% extract concentrate were 5.330 mm/y and 2.701 mm/y. Inclusion of the distillate to the electrolyte significantly reduced the corrosion rates in both acids to midpoint values of 0.0448 mm/y and 0.072 mm/y at 240 h of test. The oil extract strongly adsorbed unto the steel surface by means of chemisorption with midpoint Gibbs free energy value above -44 Kjmol-1 signifying...
Corrosion suppression effect of the combination of citrus paradise and cymbopogon oil distillates... more Corrosion suppression effect of the combination of citrus paradise and cymbopogon oil distillates on mild steel (MS) in 0.5[Formula: see text]M H2SO4 and HCl solution was studied by potentiodynamic polarization, open circuit potential measurement, optical microscopy characterization, and ATF-FTIR spectroscopy. The distillates performed adequately in both acids at all concentrations considered with average inhibition efficiency above 90%. Corrosion rate of the non-inhibited steel at 7.690 and 2.819[Formula: see text]mm/y from both acids were substantially reduced to values between 0.465 and 0.466[Formula: see text]mm/y in H2SO4 while the values in HCl are 0.081 and 0.034[Formula: see text]mm/y. The distillates exhibit mixed type inhibition performance in both acids. However, polarization plots displayed cathodic passivation effect at higher distillate concentration in H2SO4 while cathodic-anodic passivation plots were observed at all distillate concentrations in HCl solution. Corrosi...
The reinforced composite coating has been proven to offer outstanding properties and increased co... more The reinforced composite coating has been proven to offer outstanding properties and increased component life span in service. Thus, its development has found a significant place in advanced engineering applications. This study aims to reinforce Zinc-Zinc Oxide composite coatings with an organic and sustainable, eco-friendly product, scales ofMicropogonias undulatus(M. undulatus) anti-corrosion composite coating, for mild steel protection in service. The coating was developed via the electrolytic deposition route. The effects of the process parameter, deposition time, on the morphology and electrochemical properties were reported. While the Optical Microscope (O.M.) and Scanning Electron microscopy (S.E.M.) equipped with Energy Dispersive Spectroscopy (E.D.S.) were used for structural study, the PGSTAT 30 potentiostat linked to the electrochemical software NOVA 1.8 was used for the corrosion polarisation studies. The result showed excellent coating adhesion, substrate protection and...
The worldwide need for lightweight, high-quality, high-performance, and low-cost materials is pro... more The worldwide need for lightweight, high-quality, high-performance, and low-cost materials is prompting a change in emphasis from unreinforced materials to reinforced/composite materials. The mechanical properties of the MHP reinforced aluminum composite are compared to those of the unreinforced metal using the data on the corrosion performance of maize husk particulate reinforcement on high 1170 Aluminium alloy in 0.00625 M H2SO4, 3.5 wt.% NaCl and a mixture of both solutions was studied using weight loss technique to determine the corrosion rates of the specimens. Optical microscopic analysis was also carried out on the specimens to determine the effect of the reinforcement on the microstructural properties of the material before and after corrosion. The corrosion rates calculated from the weight loss study revealed differences in the corrosion characteristics of the specimens in the various solutions when compared to the control specimen. The presence of reinforcement in the matrix was discovered to positively impact the corrosion behavior of composite materials via the production of corrosion resistant oxides. The electrochemical properties of maize husk enhances the corrosion resistance of the composite due to its ability to form a protective oxide film and chemically resistant inclusions on the surface of the material.
Gravimetric and statistical analysis was utilized to assess the inhibition performance of extract... more Gravimetric and statistical analysis was utilized to assess the inhibition performance of extracts of green tea and moringa on 1070 aluminum in 0.5M H2SO4 solution. Data output showed green tea extract performed more effectively than moringa extract, and at all concentrations studied with optimal inhibition efficiency value of 95.08% compared to moringa which performed effectively at only one concentration with optimal value of 72.38%. Inhibition efficiency values for both extracts varied significantly with reference to exposure time and extract concentration. The optimal mean inhibition value for green tea and moringa extracts are 88.71% and 66.65%. However, the least standard deviation value of 6.22 was obtained for green tea extract with highest inhibition value indication stable inhibition and thermodynamic stability with reference to exposure time. Statistical data showed 90.5% of inhibition output for green tea extract and 9.52% of inhibition output for moringa extract were above 70% inhibition efficiency at margin of error of +12.6. Analysis of variance showed exposure time is the only statistically relevant variable influencing the inhibition output of green tea with statistical value of 78% while exposure time and moringa extract concentration are the both statistically relevant variables influencing the inhibition output of moringa with values of 61.02% and 24.02%.
The protection performance Aloe vulgaris (AV) and Nicotiana tabacum (NT) leaf extracts on 1070 al... more The protection performance Aloe vulgaris (AV) and Nicotiana tabacum (NT) leaf extracts on 1070 aluminum (Al) were separately studied while the combined admixture of the extracts (AVNT) on mild steel (MS) was also studied in 3.5% NaCl solution by gravimetric analysis. Data output showed AV and NT effectively stifled the redox reaction process responsible for Al corrosion in NaCl with protection performance data above 98% throughout the exposure hours signifying strong resilience of the extract molecules withstanding the corrosive anions and thermodynamic stability with respect to exposure time. AVNT performed effective on mild steel at relatively lower efficiency, but with final values above 80% efficiency. Statistical data for standard deviation shows the degree of variation of protection performance data for AV, NT and AVNT extracts from mean value is minimal signifying consistent data value with respect to exposure time. Data also showed 100% of AV and NT protection performance data are above 98% efficiency value at +0% margin of error while 14.29% of AVNT protection performance data are above 95% efficiency at margin of error of +14.97%. Data from analysis of variance shows AV extract concentration and observation time strongly influences the performance out of AV at rated value of 42.06% and 29.41%. NT extract concentration solely dominated the performance output of NT at 95.37% while the performance of AVNT was independent of its concentration with values below threshold significance. However, AVNT performance varied significantly with observation time signifying progressive improvement in performance in over time.
The protection performance of admixed Lavandula latifolia and Ricinus communis (LLRC) oil distill... more The protection performance of admixed Lavandula latifolia and Ricinus communis (LLRC) oil distillates on low carbon steel in 0.5 M H2SO4 and HCl was performed by gravimetric measurement. Data output shows LLRC distillate effectively stifled the corrosion of the carbon steel with peak protection performance of 96.35% at 1% LLRC concentration in H2SO4 solution and 88.72% at 6% LLRC concentration in HCl solution. LLRC performed more effectively in H2SO4 solution than in HCl. The performance of LLRC in H2SO4 exhibited significant non dependence on observation time while LLRC concentration strongly influenced its performance. In HCl solution observation time and LLRC concentration influenced the performance output of LLRC distillate in different proportions. Statistical evaluation rated the influence of LLRC concentration the protection performance of LLRC at 90.66% compared to 2.22% for observation time, while the corresponding values in HCl are 55.37% for LLRC concentration and 21.04% for observation time. Calculated data for standard deviation shows relatively minimal variation from mean values with respect to LLRC concentration and observation time at lower LLRC concentration in H2SO4 solution. At higher LLRC concentration, the degree of variation increases due to relative instability with respect to exposure time. The standard deviation values in HCl are significantly and relatively higher than the values obtained in H2SO4 solution due to significant deviation from mean values which signifies extensive instability with respect to exposure time. The margin of error shows 91.7% and 93.3% of LLRC protection performance data in H2SO4 and HCl solution are greater than 80% inhibition efficiency at margin of error of +6.99% and +6.31%.
Corrosion resistance of untreated (B265TiN), quenched (B265TiQ), and annealed (B265TiA) B265 tita... more Corrosion resistance of untreated (B265TiN), quenched (B265TiQ), and annealed (B265TiA) B265 titanium alloy was studied in 2–10 M H2SO4+ 10% NaCl solution at 30, 70, and 95°C by potentiodynamic polarization, potentiostatic measurement, open circuit potential measurement, and optical microscopy. B265TiN was the most resistant of the alloys to general corrosion at 30°C with values between 0.094 and 3.782 mm/year. B265TiQ exhibited the highest corrosion rate values (0.210–23.399 mm/year). Its plots show significant increase in cathodic slope. At 70 and 95°C, B265TiN exhibited the lowest corrosion rate in 2 and 6 M H2SO4+ 10% NaCl solution, while B265TiQ exhibited the corresponding highest values. Optical characterization shows B265TiN, B265TiQ, and B265TiA alloys are highly resistant to corrosion in 2 M H2SO4+ 10% NaCl at 30°C compared to 10 M H2SO4+ 10% NaCl, where marginal deterioration occurred on B265TiN, significant degradation on B265TiQ, and localized degradation on B265TiA. The...
IOP Conference Series: Materials Science and Engineering, 2022
The resilience of mild steel to electrochemical degeneration in weak electrolyte corrosion (0.5 M... more The resilience of mild steel to electrochemical degeneration in weak electrolyte corrosion (0.5 M HCl) was assessed at discrete concentrations of Norcholine derivatives by potentiodynamic polarization and open circuit potential analysis. Degradation rate of the steel substantially declined with augmentation of Norcholine concentration from 9.49 mm/y in control HCl (no Norcholine) to 0.27 mm/y at highest Norcholine value of 15%. The degradation rate at this inhibitor concentration correlates of 97.1% protection performance. Norcholine demonstrated cathodic inhibition effect from observation of the negative deviation in corrosion potential. Norcholine was also observed to indicate substantial passive reaction mechanism on the anodic polarization regions of the polarization graphs. This translates to evolution of non-porous layer on the steel exterior. Open circuit potential graphs indicate substantial variation between the inhibited and acid degraded graphs of the steel. Mathematical ...
IOP Conference Series: Materials Science and Engineering, 2022
The inhibition capability of admixed rosemary oil with cinnamon cassia oil (RC), and grapefruit o... more The inhibition capability of admixed rosemary oil with cinnamon cassia oil (RC), and grapefruit oil with lemongrass oil (GL) on GX4CrNiMo16-5-1 martensitic stainless steel (GX4ST) corrosion was studied in 6 M H2SO4/3.5% NaCl electrolyte by potentiodynamic polarization and optical microscopy characterization. Results show both admixed distillates performed effectively on GX4ST. The corrosion rate of GX4ST without the distillates at 2.82 mm/y significantly decreased to average value of 0.04 mm/y and 0.05 mm/y analogous to average inhibition efficiency of 98.64% and 98.23% for RC and GL compound. The oil distillates exhibit consistent anodic corrosion inhibition behavior at all concentrations studied. Corrosion thermodynamic calculations showed the distillates chemisorbed on the martensitic steel with Gibbs free energy values greater than -46.01 Kjmol−1 with respect to Langmuir isotherm equation which indicates negligible of lateral interaction effect among inhibitor molecules and surf...
The corrosion inhibition reaction of plant distillates and their synergistic combination effect w... more The corrosion inhibition reaction of plant distillates and their synergistic combination effect was studied. Atlas cedarwood distillate (ACW), and admixture of sage and Jojoba distillates (SJA), and admixture of jojoba and lavender distillates (JLD) were evaluated at minimal concentrations to for their corrosion inhibition effect on mild steel in 1 M H2SO4 solution. Results showed ACW reacted poorly at 1% and 2% inhibitor concentration. However, from 3% - 6% ACW concentration the final corrosion rate of 94.73%, 94.77% and 95.61% was attained at 240 h signifying effective inhibition performance. SJA inhibitor compound exhibited optimal performance at all concentrations (1% - 6% SJA) with maximum inhibition value of 98.44% at 5% SJA concentration. JLD exhibited optimal performance at all concentrations studied after 2% JLD with maximum inhibition value of 91.07% at 3% JLD concentration and 240 h exposure time. The mean values for ACW and JLD inhibition efficiency appreciated with incr...
IOP Conference Series: Materials Science and Engineering, 2021
Aluminum dross waste creates environmental burden for manufacturers and hence the need for its re... more Aluminum dross waste creates environmental burden for manufacturers and hence the need for its re-use. This experimental research assessed the engineering properties of modified asphalt using aluminium dross as a filer material. The aluminium dross used was obtained from a steel manufacturing industry. Elemental composition of the oxides was done using XRF equipment. Sieve analysis of the aluminium dross and the coarse aggregate was also assessed. Additionally, ductility, penetration, ball and ring and Marshall stability test were used in achieving the aim of this research. The outcome of the research revealed that 10-20% addition of the aluminium dross improved the stability of the modified asphalt. Physical observation revealed that the utilization of the waste stiffened the modified asphalt. The result showed that the addition of aluminium dross reduced the VMA. This will also increase the asphalt mix flushing. Additionally, at higher percentage addition of the waste the stiffnes...
IOP Conference Series: Materials Science and Engineering, 2021
Orange essential oil distillate (OOE) was studied for its inhibition performance on low carbon st... more Orange essential oil distillate (OOE) was studied for its inhibition performance on low carbon steel in 0.5 M H2SO4 and HCl aqueous electrolyte by electrochemical method and open circuit potential measurement. OOE performance was significantly proportional to it concentration with highest protection efficiency of 76.93% and 94.90% at optimal OOE concentration (10% OOE) in H2SO4 and HCl electrolyte. The performance of OOE at low concentration in H2SO4 was quite poor with inhibition efficiency values below 40%. OOE exhibited greater inhibition action in HCl solution with effective performance beginning at 4% OOE concentration compared to 6% concentration in H2SO4 electrolyte. Corrosion potential deviated basically in the anodic direction signifying the dominant inhibition effect to be through surface coverage of the steel surface. OOE exhibited mixed type corrosion inhibition. Open circuit potential graphs show OOE increases the thermodynamic fluctuation of the carbon steel in H2SO4 s...
IOP Conference Series: Materials Science and Engineering, 2021
The Inhibition efficiency of Rosemary oil (Rosmarinus officinalis) for corrosion control of high ... more The Inhibition efficiency of Rosemary oil (Rosmarinus officinalis) for corrosion control of high carbon steel was done in citric acid medium by weight loss method. The Rosmarinus officinalis was administered in the proportion of 0%, 0.50%, 1.00%, 1.50%, 2.00% and 2.50% concentration. This study unveiled that the inhibition efficiency performed excellently with maximum percentage of 88.3% at room temperature in 0.5M citric acid solution. This has shown the effectiveness of Rosmarinus officinalis inhibitor in corrosion analysis of high carbon steel.
Applications of harmless fluid derivative for the sustenance of carbon steel in corrosive environ... more Applications of harmless fluid derivative for the sustenance of carbon steel in corrosive environments are more appropriate for environmental sustainability and safety of personnel. Admixture of grapefruit and lemongrass distillates was assessed for their protective performance on plain carbon steel within 0.5 M of H2SO4 and HCl solution through weight loss analysis and optical macroscopy studies. Results shows the plant extracts effectively stifled corrosion in both acids with inhibition value range (lowest to highest) of 98.65%-99.5% in H2SO4 solution and 96.31%- 98.39% in HCl. PCS in H2SO4 and HCl electrolyte at 0% extract concentrate were 5.330 mm/y and 2.701 mm/y. Inclusion of the distillate to the electrolyte significantly reduced the corrosion rates in both acids to midpoint values of 0.0448 mm/y and 0.072 mm/y at 240 h of test. The oil extract strongly adsorbed unto the steel surface by means of chemisorption with midpoint Gibbs free energy value above -44 Kjmol-1 signifying...
Corrosion suppression effect of the combination of citrus paradise and cymbopogon oil distillates... more Corrosion suppression effect of the combination of citrus paradise and cymbopogon oil distillates on mild steel (MS) in 0.5[Formula: see text]M H2SO4 and HCl solution was studied by potentiodynamic polarization, open circuit potential measurement, optical microscopy characterization, and ATF-FTIR spectroscopy. The distillates performed adequately in both acids at all concentrations considered with average inhibition efficiency above 90%. Corrosion rate of the non-inhibited steel at 7.690 and 2.819[Formula: see text]mm/y from both acids were substantially reduced to values between 0.465 and 0.466[Formula: see text]mm/y in H2SO4 while the values in HCl are 0.081 and 0.034[Formula: see text]mm/y. The distillates exhibit mixed type inhibition performance in both acids. However, polarization plots displayed cathodic passivation effect at higher distillate concentration in H2SO4 while cathodic-anodic passivation plots were observed at all distillate concentrations in HCl solution. Corrosi...
The reinforced composite coating has been proven to offer outstanding properties and increased co... more The reinforced composite coating has been proven to offer outstanding properties and increased component life span in service. Thus, its development has found a significant place in advanced engineering applications. This study aims to reinforce Zinc-Zinc Oxide composite coatings with an organic and sustainable, eco-friendly product, scales ofMicropogonias undulatus(M. undulatus) anti-corrosion composite coating, for mild steel protection in service. The coating was developed via the electrolytic deposition route. The effects of the process parameter, deposition time, on the morphology and electrochemical properties were reported. While the Optical Microscope (O.M.) and Scanning Electron microscopy (S.E.M.) equipped with Energy Dispersive Spectroscopy (E.D.S.) were used for structural study, the PGSTAT 30 potentiostat linked to the electrochemical software NOVA 1.8 was used for the corrosion polarisation studies. The result showed excellent coating adhesion, substrate protection and...
The worldwide need for lightweight, high-quality, high-performance, and low-cost materials is pro... more The worldwide need for lightweight, high-quality, high-performance, and low-cost materials is prompting a change in emphasis from unreinforced materials to reinforced/composite materials. The mechanical properties of the MHP reinforced aluminum composite are compared to those of the unreinforced metal using the data on the corrosion performance of maize husk particulate reinforcement on high 1170 Aluminium alloy in 0.00625 M H2SO4, 3.5 wt.% NaCl and a mixture of both solutions was studied using weight loss technique to determine the corrosion rates of the specimens. Optical microscopic analysis was also carried out on the specimens to determine the effect of the reinforcement on the microstructural properties of the material before and after corrosion. The corrosion rates calculated from the weight loss study revealed differences in the corrosion characteristics of the specimens in the various solutions when compared to the control specimen. The presence of reinforcement in the matrix was discovered to positively impact the corrosion behavior of composite materials via the production of corrosion resistant oxides. The electrochemical properties of maize husk enhances the corrosion resistance of the composite due to its ability to form a protective oxide film and chemically resistant inclusions on the surface of the material.
Gravimetric and statistical analysis was utilized to assess the inhibition performance of extract... more Gravimetric and statistical analysis was utilized to assess the inhibition performance of extracts of green tea and moringa on 1070 aluminum in 0.5M H2SO4 solution. Data output showed green tea extract performed more effectively than moringa extract, and at all concentrations studied with optimal inhibition efficiency value of 95.08% compared to moringa which performed effectively at only one concentration with optimal value of 72.38%. Inhibition efficiency values for both extracts varied significantly with reference to exposure time and extract concentration. The optimal mean inhibition value for green tea and moringa extracts are 88.71% and 66.65%. However, the least standard deviation value of 6.22 was obtained for green tea extract with highest inhibition value indication stable inhibition and thermodynamic stability with reference to exposure time. Statistical data showed 90.5% of inhibition output for green tea extract and 9.52% of inhibition output for moringa extract were above 70% inhibition efficiency at margin of error of +12.6. Analysis of variance showed exposure time is the only statistically relevant variable influencing the inhibition output of green tea with statistical value of 78% while exposure time and moringa extract concentration are the both statistically relevant variables influencing the inhibition output of moringa with values of 61.02% and 24.02%.
The protection performance Aloe vulgaris (AV) and Nicotiana tabacum (NT) leaf extracts on 1070 al... more The protection performance Aloe vulgaris (AV) and Nicotiana tabacum (NT) leaf extracts on 1070 aluminum (Al) were separately studied while the combined admixture of the extracts (AVNT) on mild steel (MS) was also studied in 3.5% NaCl solution by gravimetric analysis. Data output showed AV and NT effectively stifled the redox reaction process responsible for Al corrosion in NaCl with protection performance data above 98% throughout the exposure hours signifying strong resilience of the extract molecules withstanding the corrosive anions and thermodynamic stability with respect to exposure time. AVNT performed effective on mild steel at relatively lower efficiency, but with final values above 80% efficiency. Statistical data for standard deviation shows the degree of variation of protection performance data for AV, NT and AVNT extracts from mean value is minimal signifying consistent data value with respect to exposure time. Data also showed 100% of AV and NT protection performance data are above 98% efficiency value at +0% margin of error while 14.29% of AVNT protection performance data are above 95% efficiency at margin of error of +14.97%. Data from analysis of variance shows AV extract concentration and observation time strongly influences the performance out of AV at rated value of 42.06% and 29.41%. NT extract concentration solely dominated the performance output of NT at 95.37% while the performance of AVNT was independent of its concentration with values below threshold significance. However, AVNT performance varied significantly with observation time signifying progressive improvement in performance in over time.
The protection performance of admixed Lavandula latifolia and Ricinus communis (LLRC) oil distill... more The protection performance of admixed Lavandula latifolia and Ricinus communis (LLRC) oil distillates on low carbon steel in 0.5 M H2SO4 and HCl was performed by gravimetric measurement. Data output shows LLRC distillate effectively stifled the corrosion of the carbon steel with peak protection performance of 96.35% at 1% LLRC concentration in H2SO4 solution and 88.72% at 6% LLRC concentration in HCl solution. LLRC performed more effectively in H2SO4 solution than in HCl. The performance of LLRC in H2SO4 exhibited significant non dependence on observation time while LLRC concentration strongly influenced its performance. In HCl solution observation time and LLRC concentration influenced the performance output of LLRC distillate in different proportions. Statistical evaluation rated the influence of LLRC concentration the protection performance of LLRC at 90.66% compared to 2.22% for observation time, while the corresponding values in HCl are 55.37% for LLRC concentration and 21.04% for observation time. Calculated data for standard deviation shows relatively minimal variation from mean values with respect to LLRC concentration and observation time at lower LLRC concentration in H2SO4 solution. At higher LLRC concentration, the degree of variation increases due to relative instability with respect to exposure time. The standard deviation values in HCl are significantly and relatively higher than the values obtained in H2SO4 solution due to significant deviation from mean values which signifies extensive instability with respect to exposure time. The margin of error shows 91.7% and 93.3% of LLRC protection performance data in H2SO4 and HCl solution are greater than 80% inhibition efficiency at margin of error of +6.99% and +6.31%.
Corrosion resistance of untreated (B265TiN), quenched (B265TiQ), and annealed (B265TiA) B265 tita... more Corrosion resistance of untreated (B265TiN), quenched (B265TiQ), and annealed (B265TiA) B265 titanium alloy was studied in 2–10 M H2SO4+ 10% NaCl solution at 30, 70, and 95°C by potentiodynamic polarization, potentiostatic measurement, open circuit potential measurement, and optical microscopy. B265TiN was the most resistant of the alloys to general corrosion at 30°C with values between 0.094 and 3.782 mm/year. B265TiQ exhibited the highest corrosion rate values (0.210–23.399 mm/year). Its plots show significant increase in cathodic slope. At 70 and 95°C, B265TiN exhibited the lowest corrosion rate in 2 and 6 M H2SO4+ 10% NaCl solution, while B265TiQ exhibited the corresponding highest values. Optical characterization shows B265TiN, B265TiQ, and B265TiA alloys are highly resistant to corrosion in 2 M H2SO4+ 10% NaCl at 30°C compared to 10 M H2SO4+ 10% NaCl, where marginal deterioration occurred on B265TiN, significant degradation on B265TiQ, and localized degradation on B265TiA. The...
IOP Conference Series: Materials Science and Engineering, 2022
The resilience of mild steel to electrochemical degeneration in weak electrolyte corrosion (0.5 M... more The resilience of mild steel to electrochemical degeneration in weak electrolyte corrosion (0.5 M HCl) was assessed at discrete concentrations of Norcholine derivatives by potentiodynamic polarization and open circuit potential analysis. Degradation rate of the steel substantially declined with augmentation of Norcholine concentration from 9.49 mm/y in control HCl (no Norcholine) to 0.27 mm/y at highest Norcholine value of 15%. The degradation rate at this inhibitor concentration correlates of 97.1% protection performance. Norcholine demonstrated cathodic inhibition effect from observation of the negative deviation in corrosion potential. Norcholine was also observed to indicate substantial passive reaction mechanism on the anodic polarization regions of the polarization graphs. This translates to evolution of non-porous layer on the steel exterior. Open circuit potential graphs indicate substantial variation between the inhibited and acid degraded graphs of the steel. Mathematical ...
IOP Conference Series: Materials Science and Engineering, 2022
The inhibition capability of admixed rosemary oil with cinnamon cassia oil (RC), and grapefruit o... more The inhibition capability of admixed rosemary oil with cinnamon cassia oil (RC), and grapefruit oil with lemongrass oil (GL) on GX4CrNiMo16-5-1 martensitic stainless steel (GX4ST) corrosion was studied in 6 M H2SO4/3.5% NaCl electrolyte by potentiodynamic polarization and optical microscopy characterization. Results show both admixed distillates performed effectively on GX4ST. The corrosion rate of GX4ST without the distillates at 2.82 mm/y significantly decreased to average value of 0.04 mm/y and 0.05 mm/y analogous to average inhibition efficiency of 98.64% and 98.23% for RC and GL compound. The oil distillates exhibit consistent anodic corrosion inhibition behavior at all concentrations studied. Corrosion thermodynamic calculations showed the distillates chemisorbed on the martensitic steel with Gibbs free energy values greater than -46.01 Kjmol−1 with respect to Langmuir isotherm equation which indicates negligible of lateral interaction effect among inhibitor molecules and surf...
The corrosion inhibition reaction of plant distillates and their synergistic combination effect w... more The corrosion inhibition reaction of plant distillates and their synergistic combination effect was studied. Atlas cedarwood distillate (ACW), and admixture of sage and Jojoba distillates (SJA), and admixture of jojoba and lavender distillates (JLD) were evaluated at minimal concentrations to for their corrosion inhibition effect on mild steel in 1 M H2SO4 solution. Results showed ACW reacted poorly at 1% and 2% inhibitor concentration. However, from 3% - 6% ACW concentration the final corrosion rate of 94.73%, 94.77% and 95.61% was attained at 240 h signifying effective inhibition performance. SJA inhibitor compound exhibited optimal performance at all concentrations (1% - 6% SJA) with maximum inhibition value of 98.44% at 5% SJA concentration. JLD exhibited optimal performance at all concentrations studied after 2% JLD with maximum inhibition value of 91.07% at 3% JLD concentration and 240 h exposure time. The mean values for ACW and JLD inhibition efficiency appreciated with incr...
IOP Conference Series: Materials Science and Engineering, 2021
Aluminum dross waste creates environmental burden for manufacturers and hence the need for its re... more Aluminum dross waste creates environmental burden for manufacturers and hence the need for its re-use. This experimental research assessed the engineering properties of modified asphalt using aluminium dross as a filer material. The aluminium dross used was obtained from a steel manufacturing industry. Elemental composition of the oxides was done using XRF equipment. Sieve analysis of the aluminium dross and the coarse aggregate was also assessed. Additionally, ductility, penetration, ball and ring and Marshall stability test were used in achieving the aim of this research. The outcome of the research revealed that 10-20% addition of the aluminium dross improved the stability of the modified asphalt. Physical observation revealed that the utilization of the waste stiffened the modified asphalt. The result showed that the addition of aluminium dross reduced the VMA. This will also increase the asphalt mix flushing. Additionally, at higher percentage addition of the waste the stiffnes...
IOP Conference Series: Materials Science and Engineering, 2021
Orange essential oil distillate (OOE) was studied for its inhibition performance on low carbon st... more Orange essential oil distillate (OOE) was studied for its inhibition performance on low carbon steel in 0.5 M H2SO4 and HCl aqueous electrolyte by electrochemical method and open circuit potential measurement. OOE performance was significantly proportional to it concentration with highest protection efficiency of 76.93% and 94.90% at optimal OOE concentration (10% OOE) in H2SO4 and HCl electrolyte. The performance of OOE at low concentration in H2SO4 was quite poor with inhibition efficiency values below 40%. OOE exhibited greater inhibition action in HCl solution with effective performance beginning at 4% OOE concentration compared to 6% concentration in H2SO4 electrolyte. Corrosion potential deviated basically in the anodic direction signifying the dominant inhibition effect to be through surface coverage of the steel surface. OOE exhibited mixed type corrosion inhibition. Open circuit potential graphs show OOE increases the thermodynamic fluctuation of the carbon steel in H2SO4 s...
IOP Conference Series: Materials Science and Engineering, 2021
The Inhibition efficiency of Rosemary oil (Rosmarinus officinalis) for corrosion control of high ... more The Inhibition efficiency of Rosemary oil (Rosmarinus officinalis) for corrosion control of high carbon steel was done in citric acid medium by weight loss method. The Rosmarinus officinalis was administered in the proportion of 0%, 0.50%, 1.00%, 1.50%, 2.00% and 2.50% concentration. This study unveiled that the inhibition efficiency performed excellently with maximum percentage of 88.3% at room temperature in 0.5M citric acid solution. This has shown the effectiveness of Rosmarinus officinalis inhibitor in corrosion analysis of high carbon steel.
The corrosion of austenitic stainless steel (type 304) in dilute sulphuric acid solutions in addi... more The corrosion of austenitic stainless steel (type 304) in dilute sulphuric acid solutions in addition to recrystalized sodium chloride concentrates in the presence of specific proportions of phenylamine was studied with the aid of polarization resistance technique, electrode potential monitoring and coupon method. Results showed the overwhelming influence of the compound in corrosion inhibition with an inhibition efficiency of 97.5% from coupon analysis and 86.10% from polarization test at highest observed concentration of the inhibitor. Corrosion potential measurement showed potentials well with passivation values. Corrosion rate decreased progressively with increase in concentration of phenylamine. Adsorption of the compound on the steel surface followed the Langmuir isotherm model. Thermodynamic calculations showed the interaction mode with the steel to be physiochemical. Observation from scanning electron microscopy and x-ray diffractometry showed the electrochemical impact on the surface topography and the phase compounds of the steel samples studied. Results from statistical analysis depict the sharp influence of inhibitor concentration on the electrochemical performance of the compound.
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