Search

Highlights: [•] Novel approach to the study of electrochemical migration in thin electrolyte layers. [•] Tin dendrites tend to grow in electrolytes of low and high Cl− concentration. [•] Tin dendrites do not grow in electrolytes of medium Cl− concentration. [•] Real time observation of pH distribution on the electrodes. [•] Precipitates consist of stannic and stannous hydroxides or oxides. [ABSTRACT FROM AUTHOR]

Corrosion of X80 pipeline steel under sulfate-reducing bacterium (SRB) biofilms, which formed in a culture medium at different times, in a simulated CO 2 -saturated oilfield produced water was investigated. Both planktonic and sessile SRB cells survived after 21 days of immersion in the water under carbon source starvation. The biofilms pre-cultured with a longer time increased the corrosion rate of the steel. At 37 °C, it took about 4 days for SRB to grow and then participate in the steel corrosion. The SRB also facilitated localized corrosion. The SRB biofilm, once deactivated, would no longer affect the steel corrosion. [ABSTRACT FROM AUTHOR]

The corrosion behavior of X65 steel in water-saturated supercritical CO 2 containing O 2 and/or H 2 S impurities was investigated by means of weight loss measurements and surface characterization. The results showed that the addition of O 2 or H 2 S impurities increased the corrosion rate of X65 steel in water-saturated supercritical CO 2 system. The effect of H 2 S on the corrosion of X65 steel was greater than that of O 2 . The corrosion was more severe with the coexistence of O 2 and H 2 S. The change in corrosion behavior was attributed to the fact that low concentrations of O 2 and/or H 2 S can notably change the corrosion mechanism. [ABSTRACT FROM AUTHOR]

Inhibition effect of an imidazoline derivative, dodecanoic acid and dodecylamine against CO 2 corrosion and microbiologically influence corrosion in a CO 2 -containing oilfield produced water was studied using surface analysis, weight loss and electrochemical measurements. Results indicated that dodecanoic acid could inhibit the adhesion of iron-oxidizing bacteria (IOB) significantly on carbon steel coupons, but had no effect on the planktonic IOB growth. Its inhibition efficiency reached 88.2% after 43 days of incubation. An imidazoline derivative was found to inhibit the adhesion of IOB on the steel surface, and contributed to lower inhibition effect. [ABSTRACT FROM AUTHOR]

In this paper, the effect of a magneticfield (MF) on biomineralization and corrosion behavior of Q235 carbon steel were studied using surface analysis, weight loss and electrochemical measurements. Experimental results showed that MF inhibited the growth of iron-oxidizing bacteria (IOB) and the corrosion of Q235 carbon steel. MF reduced the largest pit depth by half, while it reduced pit population density from 50 pits cm −2 to 10 pits cm −2 . MF also altered the morphology of biomineralization film, leading to the formation of a more compact biomineralization film which contributed to the lower corrosion rate. [ABSTRACT FROM AUTHOR]

Corrosion inhibition by benzalkonium chloride (BKC) against anaerobic CO 2 corrosion and microbiologically influenced corrosion was studied using surface analysis, weight loss and electrochemical measurements. Results showed that the minimal bactericidal concentration of BKC against Desulfotomaculum nigrificans ( D. nigrificans ) was 40 mg L −1 . While at this concentration the planktonic D. nigrificans cell count could recover after 21-day incubation, it resulted in 4 log reduction in sessile D. nigrificans cell count. When 80 mg L −1 BKC was used, both planktonic and sessile D. nigrificans became undetectable. It was found that at these concentrations, BKC reduced both uniform corrosion and pitting corrosion. [ABSTRACT FROM AUTHOR]

The effect of tri-sodium citrate dehydrate on the electrochemical migration of tin in thin electrolyte layers containing chloride ions was investigated through potentiodynamic polarization, cyclic voltammetry, scanning electron microscopy, X-ray photoelectron spectroscopy, and optical techniques. The effects of applied bias voltage and concentration of citrate ions were also studied. Results showed that tri-sodium citrate dehydrate acts as an inhibitor by suppressing anodic dissolution and metallic ion transfer through the formation of tin citrate complexes. The mechanisms involved were proposed to explain the inhibition effect. [ABSTRACT FROM AUTHOR]

In this paper, the corrosion behavior of Q235 carbon steel in the presence of Chlorella vulgaris ( C. vulgaris ) was investigated by surface analysis, weight loss and electrochemical measurements. Results showed that the average corrosion rate in the presence of C. vulgaris was approximately 4 times as high as that in the absence of C. vulgaris . The corrosion rate in the daytime was higher than that in the night in the presence of C. vulgaris . The local corrosion was observed and the corrosion process of specimen was closely related to the activity of C. vulgaris . [ABSTRACT FROM AUTHOR]

The corrosion behavior of carbon steel was investigated in the presence of SRB and IOB separately in their respective culture media and in the mixed culture of SRB and IOB in artificially produced water with 4.2 mg/L dissolved oxygen. The results showed that IOB inhibited the growth of planktonic SRB, but promoted the growth of sessile SRB when SRB was cultured together with IOB. The mixture of SRB and IOB had a synergistic effect enhancing the pitting corrosion of the coupons. The limited amount of dissolved oxygen played a key role in the formation of corrosion products. [ABSTRACT FROM AUTHOR]