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This study aims to investigate the effect of Cr/ C ratio on wear and corrosion behavior of a group of highCr white cast iron (HCCI) alloys. Three different alloys of HCCI with different chemical compositions were tested against 3.5 % NaCl, 0.5 M H 2 SO 4 , and 0.5 M NaOH solutions as corrosive media. Electrochemical polarization technique has been used to determine the corrosion current density. The microstructure characteristics of HCCI alloys were analyzed by using optical microscope, SEM, EDS, and XRD. XRD analysis reveals that the microstructure of the HCCI alloys is composed of a network of chromiumrich carbides (M 7 C 3 ) in an austenitic matrix. The abrasive wear resistance of HCCI alloys was found to be rely on their chemical composition and microstructure. The corrosion resistance of the HCCI alloys strongly depends on the Cr/C ratio and the ratio of chromium content in the M 7 C 3 carbide to that in the matrix (CrM 7 C 3 /Matrix). The experimental results of this study showed that the alloy HCCI-2 with the lower Cr/C ratio exhibited the lowest abrasive wear loss while the alloy HCCI-1 with higher Cr/ C ratio exhibited the highest abrasive wear loss. On the other hand, the HCCI-1 alloy was the most corrosion resistant and revealed the lowest current density. In addition, the corrosion current density of all specimens is elevated in 0.5 M H 2 SO 4 solution in comparison with 3.5 wt% NaCl and 0.5 M NaOH solutions.

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In this paper the anti-bacterial and the anti-corrosion effect of two different ionic liquids, namely 1-(2-hydroxyethyl)-3-methylimidazolinium chloride ([OH-EMIm]Cl) and 1-ethyl-3-methyleimidazolinium chloride ([EMIm]Cl) was demonstrated. The results revealed that the corrosion inhibition influence of the ionic liquid [OH-EMIm]Cl is higher than that of the ionic liquid [EMIm]Cl. Furthermore, the ionic liquid [OH-EMIm]Cl showed better biocidal influence compared with the ionic liquid [EMIm]Cl. This indicates the synergistic effect due to the incorporation of the hydroxyl group into the side chain of the imidazolium cation leading to enhanced antibacterial and anticorrosion effect.

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IntroductionReject brines and carbon dioxide are two forms of environmental pollutants that we are facing in the course of obtaining fresh water from sea water. The common practice in dealing with these huge amounts of reject brine is to discharge back into the sea affecting seriously the aquatic life. To recover and extract valuable minerals found in these rejects is the prime objective of this work. In particular, magnesium chloride is targeted as a raw material to produce magnesium metal. Magnesium is the eighth most abundant element in the earth's crust but does not occur uncombined in nature. One cubic kilometer of sea water contains a minimum of one million tons magnesium, which makes the sea a "storehouse" of about 1.7 × 10 24 tons.In addition, magnesium chloride is found in seawater, brines, and salt wells. Magnesium (Mg) exists in sea water as ions of magnesium. It is a constituent of the chlorophyll in green plants and is necessary in the diet of animals and humans ions of magnesium. Figure 1, depicts the concentration of magnesium and magnesium chloride in sea water. When it comes to the mineral salts found in sea water, the major components of natural sea water determining their solubility properties are: Na . According to C Balarew [1] it is usually assumed that the major constituents present in the sea show constant relative proportions. He further added that the variations in the composition of waters from different seas are due only to the changes in the amount of water present. Accordingly, one can conclude that the composition-density diagram shown in Figure 2 for the initial composition of Black Sea-Water is valid for every sea water type. Separation sequence of salts during sea water evaporationWhen seawater (composition is given in Table 1) is evaporated soluble salts will be formed, at different stages during the evaporation. The crystallization of the salts dissolved in seawater is governed by their solubility products and occurs at different concentration levels. When seawater is concentrated gradually, brine concentration increases leading to the successive precipitation of the least soluble salts first. For example, iron oxide and calcium carbonate start to crystallize first, in very small quantities, followed by calcium sulfate (known as gypsum). It is reported that about 30-50 kg of gypsum comes out for every ton of salt produced. Right at this stage, sodium chloride starts to crystallize AbstractSea water bitterns (SWB) are encountered in the processes of desalination and sea-salt production where large quantities of bitterns and brines are produced, either as by-products, or as waste products. They could be described as "exhausted brines". In theory, for every ton of sea-salt produced about one cubic meter of bittern is produced and is available for further processing. To exploit valuable salt products, in particular MgCl2 from sea water in desalination plants and/or salt production, various methods were carried out, in particular by the author and his colleagues. Mainly they cons...

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