The dissolution of carbon steel in 5% HCl in the temperature range of 30~90℃ was inhibited by two organic compounds having the general formula: ClR NH2(CH2)n NH2 RCl where R is a benzyl group. The behaviour of these ...The dissolution of carbon steel in 5% HCl in the temperature range of 30~90℃ was inhibited by two organic compounds having the general formula: ClR NH2(CH2)n NH2 RCl where R is a benzyl group. The behaviour of these inhibitors in acidic medium were investigated using weight loss method, open circuit potential and linear polarization technique. These inhibitors provided satisfactory corrosion inhibition for carbon steel in hydrochloric acid solutions even at higher temperature and acid concentration (10%). The electrochemical results showed that the polarization resistance (Rp) values increased with increasing inhibitor concentration, also the corrosion current decreased and a higher inhibition efficiency was obtained. The protective properties of these two organic inhibitors were attributed to the chemisorption mechanism展开更多
ASTM A182 F51 duplex stainless steel with a 50:50 ratio of austenite to ferrite microstructure is a material used in mechanical engineering.Its uses include the manufacturing of equipment and components subject to aci...ASTM A182 F51 duplex stainless steel with a 50:50 ratio of austenite to ferrite microstructure is a material used in mechanical engineering.Its uses include the manufacturing of equipment and components subject to acidification or acid stimulation for oil and gas industries.During acid stimulation or acidification,hydrochloric acid(HCl)solution with concentrations ranging from 5%to 28%(by volume)is injected into the limestone(CaCO3)and dolomite(CaCO3·MgCO3)reservoir rock to restore permeability and consequently increase oil well productivity.Therefore,it is important to use a corrosion inhibitor,such as propargyl alcohol,to prevent or inhibit the aggressive attack of HCl on duplex stainless steel.The present study evaluates the corrosion resistance of ASTM A182 F51 stainless steel using gravimetric(mass loss)and electrochemical(polarization)tests.Studies were completed with and without the addition of 500 and 1,000 mg/L propargyl alcohol in HCl solutions with concentrations of 10%and 15%(by volume)at temperatures of 25,40 and 55°C.The good protection by propargyl alcohol of duplex steel immersed in HCl is observed.展开更多
The effect of hydrochloric acid concentration on stainless steel (Fe6956) at temperature range 303 - 333 ± 1 K has been studied using weight loss, thermometric and electrochemical polarization techniques. The cor...The effect of hydrochloric acid concentration on stainless steel (Fe6956) at temperature range 303 - 333 ± 1 K has been studied using weight loss, thermometric and electrochemical polarization techniques. The corrosion rate of the stainless steel was found to be dependent on both temperature variation and acid concentration. The potentiostatic study showed that the active passive transition depends strongly on acid concentration while the weight loss measurements revealed that 2 M HCl at temperature 333 K had an appreciable corrosion rate which corresponds to 14.04 × 10﹣3 reaction number (RN) got from thermometric monitoring. Arrhenius equation and transition state theory were used to calculate kinetic and thermodynamic parameter such as Ea, ΔH* and ΔS*. Results obtained showed that corrosion reaction of Fe6956 in HCl is spontaneous and there is good agreement between the data got from the techniques employed.展开更多
The application of statistical analysis and quantum chemical models on the corrosion inhibition of mild steel in hydrochloric acid in presence of phenylthiourea(PTU) as corrosion inhibitor have been investigated.Two m...The application of statistical analysis and quantum chemical models on the corrosion inhibition of mild steel in hydrochloric acid in presence of phenylthiourea(PTU) as corrosion inhibitor have been investigated.Two mathematical models were used,second order polynomial model and Arrhenius type equation model.STATISTICA software based on Levenberg-Marquardt estimation method was used to evaluate the coefficients of two Models.It follows that the two models were suitable to represent the corrosion rate data at different conditions.The correlation coefficient of second order polynomial model was 0.973.while for the Arrhenius type model was 0.919.The structure of inhibitor was optimized by ArgusLab 4.0.1 package.The quantum chemical parameters(Ehomo.Elumo.△E,and dipole momentμt) were estimated by PM3-SCF method.展开更多
文摘The dissolution of carbon steel in 5% HCl in the temperature range of 30~90℃ was inhibited by two organic compounds having the general formula: ClR NH2(CH2)n NH2 RCl where R is a benzyl group. The behaviour of these inhibitors in acidic medium were investigated using weight loss method, open circuit potential and linear polarization technique. These inhibitors provided satisfactory corrosion inhibition for carbon steel in hydrochloric acid solutions even at higher temperature and acid concentration (10%). The electrochemical results showed that the polarization resistance (Rp) values increased with increasing inhibitor concentration, also the corrosion current decreased and a higher inhibition efficiency was obtained. The protective properties of these two organic inhibitors were attributed to the chemisorption mechanism
文摘ASTM A182 F51 duplex stainless steel with a 50:50 ratio of austenite to ferrite microstructure is a material used in mechanical engineering.Its uses include the manufacturing of equipment and components subject to acidification or acid stimulation for oil and gas industries.During acid stimulation or acidification,hydrochloric acid(HCl)solution with concentrations ranging from 5%to 28%(by volume)is injected into the limestone(CaCO3)and dolomite(CaCO3·MgCO3)reservoir rock to restore permeability and consequently increase oil well productivity.Therefore,it is important to use a corrosion inhibitor,such as propargyl alcohol,to prevent or inhibit the aggressive attack of HCl on duplex stainless steel.The present study evaluates the corrosion resistance of ASTM A182 F51 stainless steel using gravimetric(mass loss)and electrochemical(polarization)tests.Studies were completed with and without the addition of 500 and 1,000 mg/L propargyl alcohol in HCl solutions with concentrations of 10%and 15%(by volume)at temperatures of 25,40 and 55°C.The good protection by propargyl alcohol of duplex steel immersed in HCl is observed.
文摘The effect of hydrochloric acid concentration on stainless steel (Fe6956) at temperature range 303 - 333 ± 1 K has been studied using weight loss, thermometric and electrochemical polarization techniques. The corrosion rate of the stainless steel was found to be dependent on both temperature variation and acid concentration. The potentiostatic study showed that the active passive transition depends strongly on acid concentration while the weight loss measurements revealed that 2 M HCl at temperature 333 K had an appreciable corrosion rate which corresponds to 14.04 × 10﹣3 reaction number (RN) got from thermometric monitoring. Arrhenius equation and transition state theory were used to calculate kinetic and thermodynamic parameter such as Ea, ΔH* and ΔS*. Results obtained showed that corrosion reaction of Fe6956 in HCl is spontaneous and there is good agreement between the data got from the techniques employed.
基金Supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (2015BAD16B01)Tianjin Key Technology Research and Development Support Program (13ZCDNC01900)
文摘The application of statistical analysis and quantum chemical models on the corrosion inhibition of mild steel in hydrochloric acid in presence of phenylthiourea(PTU) as corrosion inhibitor have been investigated.Two mathematical models were used,second order polynomial model and Arrhenius type equation model.STATISTICA software based on Levenberg-Marquardt estimation method was used to evaluate the coefficients of two Models.It follows that the two models were suitable to represent the corrosion rate data at different conditions.The correlation coefficient of second order polynomial model was 0.973.while for the Arrhenius type model was 0.919.The structure of inhibitor was optimized by ArgusLab 4.0.1 package.The quantum chemical parameters(Ehomo.Elumo.△E,and dipole momentμt) were estimated by PM3-SCF method.
