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The second edition of this textbook on physical electrochemistry, written by two experienced teachers of physical chemistry, corrosion engineering and materials science and engineering, covers the current knowledge which should be transferred to students of these fields.
In 20 chapters the fundamentals of electrochemistry, the most important electrochemical measurement techniques and applications of electrochemistry are covered.
It can be concluded that this study fulfills its intension of “serving as a key textbook in undergraduate courses” dealing with electrochemistry and being “a reference source for graduated students, researchers and engineers” interested in this field. Teachers will find sufficient content for preparing lectures on this topic. Even self‐learning is well supported by the clear structure, presented content and provided sources for further reading.
This contribution provides current findings regarding materials susceptibility for carbon capture, utilization and storage (CCUS) applications. Basing on results gathered in 2 German long-term projects (COORAL and CLUSTER) suitable materials are introduced as well as dominating impurities of the CO2-stream and corrosion mechanisms. Investigations cover the whole CCUS process chain and provide material recommendations for certain parts.
This contribution provides current findings regarding materials susceptibility for carbon capture, utilization and storage (CCUS) applications. Basing on results gathered in 2 German long-term projects (COORAL and CLUSTER) suitable materials are introduced as well as dominating impurities of the CO2-stream and corrosion mechanisms. Investigations cover the whole CCUS process chain and provide material recommendations for certain parts.
Susceptibility of 304 stainless steel to crevice corrosion in electrochemically active fluids
(2019)
The susceptibility of AISI 304 stainless steel to crevice corrosion on the effect of contact with electrochemically active fluids was investigated using exposure and stepwise potentiostatic polarisation. Crevice materials made up of 304 SS and Polyether ether ketone (PEEK) forming two kinds of crevices including 304 SS-to-PEEK and 304 SS-to-304 SS were tested.
Susceptibility of 304 stainless steel to crevice corrosion in electrochemically active fluids
(2019)
The susceptibility of AISI 304 stainless steel to crevice corrosion on the effect of contact with electrochemically active fluids was investigated using exposure and stepwise potentiostatic polarisation. Crevice materials made up of 304 SS and Polyether ether ketone (PEEK) forming two kinds of crevices including 304 SS-to-PEEK and 304 SS-to-304 SS were tested.
In Europe biodiesel gained from rapeseeds are considered as an alternative to common fossil fuels due to its environmental performance and its independence from import of raw materials. Biodiesel is also suitable to serve as blending component to heating oil. In that case, it must be considered that changes of fuel composition might cause material degradation.
The objective of this research was to investigate the resistance of metallic materials exposed to heating oil, heating oil blend B20 with 20 % biodiesel and pure biodiesel. Furthermore, the resistance of metals to eight-year aged B10 and six-year aged pure biodiesel was evaluated. Ageing of biodiesel forms acids and water which might propagate metal corrosion. The investigated metals (aluminium, unalloyed steel, austenitic CrNi-steel, copper, die cast zinc and brass) are commonly used for components in middle distillate facilities.
According to DIN 50905-4 the immersed metals were exposed in a climate chamber at 50°C for 4 weeks. The metallic materials were evaluated as resistant if the annual corrosion rate due to uniform corrosion remained under 0.1 mm/year and no localized corrosion in the form of pitting occurred.
The corrosion rates of the exposed materials stayed far below the limit of 0.1 mm/year for all tested fuels. An exception was die cast zinc ZP0410 in eight-year aged B10; a corrosion rate up to 0.3 mm/year due to uniform corrosion was measured. In no case localized corrosion occurred. Copper and brass caused discolouration of biodiesel from yellow to green.
In conclusion, the tested metallic materials were resistant in heating oil, heating oil blend B20 and pure biodiesel at 50 °C. Even the metals exposed to six-year aged biodiesel and eight-year aged B10 showed no uniform or localized corrosion; except for zinc, which was not resistant in eight-year aged B10.
Carbon Capture and Storage (CCS) is identified as an excellent technology to reach the target of CO2 reduction. However, the safety issue and cost-effectiveness hinder the future of CCS. For the reliability and safety issues of injection wells, the corrosion resistance of the materials used needs to be determined.
In this study, representative low-cost materials including carbon steel 1.8977 and low alloyed steel 1.7225 were investigated in simulated pore water at 333 K and under CO2 saturation condition to represent the worst-case scenario: CO2 diffusion and aquifer fluid penetration. These simulated pore waters were made from relevant cement powder to mimic the realistic casing-cement interface. Electrochemical studies were carried out using the pore water made of cement powder dissolved in water in comparison with those dissolved in synthetic aquifer fluid, to reveal the effect of cement as well as formation water on the steel performance. Two commercially available types of cement were investigated: Dyckerhoff Variodur® and Wollastonite. Variodur® is a cement containing high performance binder with ultra-fine blast furnace slag which can be used to produce high acid resistance concrete. On the other hand, Wollastonite is an emerging natural material mainly made of CaSiO3 which can be hardened by converting to CaCO3 during CO2 injection.
The results showed the pH-reducing effect of CO2 on the simulated pore water/aquifer (from more than 10 to less than 5) leading to the active corrosion process that happened on both 1.8977 and 1.7225. Electrochemical characterization showed negative free corrosion potential and polarisation curves without passive behaviors. The tested coupons suffered from pitting corrosion, which was confirmed by surface analysis. Interestingly, basing on the pit depth measurements from the tested coupons and the hardness of cement powder, it is suggested that Variodur® performed better than Wollastonite in both aspects. The electrochemical data was compared to that resulted from exposure tests to give a recommendation on material selection for bore-hole construction.