Presence Of KCl Research Articles

Impacts of Temperature and KCl on Corrosion Behavior of 12Cr1MoVG and T91 in HCl-Containing Atmosphere

The corrosion behavior of 12Cr1MoVG and T91 was investigated in a HCl-containing simulated atmosphere. Exposure experiments were divided into two groups to study two key factors, i.e., temperature and KCl, affecting high-temperature corrosion in biomass-fired boiler. One group was conducted at the temperatures of 400, 500 and 600 °C. The other was carried out at 500 °C with KCl-coated specimens. Corrosion kinetics were plotted on the basis of mass gain. The results showed that, for both alloys tested, the corrosion rates were very temperature dependent and greatly affected by the presence of KCl. The total mass gains of the specimens increased significantly with temperature increase as well as KCl coating. The results also showed that T91 was more corrosion resistant than 12Cr1MoVG under the conditions in this paper. Micro-morphology studies of the corroded specimens were conducted. The results supported the theory that the corrosion process followed an active oxidation mechanism.

The Influence of Various Chloride Salts to Reduce Sodium Content on the Quality Parameters of Şalgam (Shalgam): A Traditional Turkish Beverage Based on Black Carrot

Sodium chloride is essential in şalgam processing affecting the flavour and microbiological stability of the final product. However, reduction of sodium salt in şalgam beverage is essential due to consumers’ demand for low-sodium foods as well as recommendation of health authorities. NaCl was replaced both partially and totally by KCl and CaCl2 in the present study. Experimental design was established to investigate the effects of five different combinations (1.7% NaCl (control treatment); 0.85% NaCl–0.85% KCl; 0.85% NaCl–0.85% CaCl2; 0.85% KCl–0.85% CaCl2, and 0.56% NaCl–0.56% KCl–0.56% CaCl2) of chloride salts on microbiological, chemical, and sensory qualities of şalgam. Lactic acid bacteria (LAB) were present in populations ranging from 8.0 to 8.61 log cfu/mL while total yeasts were 6.89 to 7.12 log cfu/mL at the end of the process. The maximum number of LAB was detected in the fermentation employed NaCl + KCl salts combination. Regarding the microbiological profile, LAB growth was stimulated significantly in presence of KCl while yeast patterns were not linked to different salt treatments. The final values of total acidity (TA) and pH for şalgam were found between 7.40 and 8.71 g/L and 3.26–3.47, respectively. Concerning physicochemical attributes, pH decreased when CaCl2 increased while TA is higher in the presence of CaCl2. Şalgam juice fermented with 0.85% NaCl–0.85% KCl mineral salt combination received the best sensory results among the different salt substitutions. Results demonstrate that NaCl can be replaced in şalgam with KCl by 50%, without affecting the traditional taste of şalgam in order to meet consumers’ demand for low-sodium dietary intake.

Tribo-rheometry behaviour and gel strength of κ-carrageenan and gelatin solutions at concentrations, pH and ionic conditions used in dairy products

Understanding the flow and lubrication properties of hydrocolloids, commonly used to enhance the mouthfeel properties of various dairy products can provide valuable information to manufacturers. The current study examined the lubrication (tribology) and rheological properties of gelatin (0.2–3.0%, w/w) and carrageenan (0.01–0.7%, w/w) in the concentrations ideally added in dairy products in the presence of KCl (0–0.3%, w/w) and CaCl2 (0–3.0%, w/w) within the pH range of 4.0–8.0. Additionally, the hardness and fracturability of the corresponding gels formed at various pH, ionic and concentration of gelatin and κ-carrageenan conditions were determined using a texture analyser. Both the flow and tribological behaviors depended on the pH, addition of salts and dosage of hydrocolloids. Near its isoelectric point, gelatin solution had the lowest viscosity, gel strength, lubrication property and poor visual aspect of formed gel. Carrageenan solution had the highest viscosity and best lubrication property at neutral pH. The strength of formed gels from carrageenan solution was low in acid condition, and the formed gels had unchanged visual aspect. Adding salts improved the viscosity and tribology property, and to some extent increased the gel strength while lower gel strength was obtained when the addition of CaCl2 was beyond 0.8% for carrageenan formed gel. κ-carrageenan increased the viscosity more significantly than gelatin. However, the gelatin solution exhibited good lubrication property during low and medium sliding speed, which is good for soft dairy products that do not require much chewing.

Effect of potassium chloride on the solvation behavior of caffeine, theophylline and theobromine: Volumetric, viscometric, calorimetry and spectroscopic approach

The density (ρ), speed of sound (u), viscosity (η) and enthalpy of dilution (q) measurements for methylxanthines (caffeine, theophylline and theobromine) in aqueous medium and in aqueous solutions of (0.10–1.00) mol·kg−1 KCl covering a temperature range T = (288.15–318.15) K and at p = 101.325 kPa have been accomplished using a density and sound velocity meter, Micro-Ubbelohde type capillary viscometer and Isothermal Titration Calorimetry, respectively. Transfer parameters evaluated from the data suggest that competition among various interactions exists at low and high molalities of KCl(aq.) solutions. The increase in bitterness and decrease in hydration number of methylxanthines with the mB values have been observed. The dehydration effect of KCl(aq.) at low molalities on the methylxanthines has also been established using ITC. Positive change in the chemical shifts (1H NMR) and increase in absorption intensity (UV–vis) of methylxanthines in the presence of KCl(aq.) further support our results.

Positioning cyanamide defects in g-C3N4: Engineering energy levels and active sites for superior photocatalytic hydrogen evolution

g-C3N4 has recently emerged as a promising photocatalyst for solar energy conversion. Nonetheless, attempts to enhance its inherently low activity are rarely based on precise molecular tunability strategy. In this study, two-type cyanamide defects-grafting g-C3N4 (CCN) was prepared through the thermal polymerization of thiourea in the presence of KCl. Stable potassium isothiocyanate (KSCN) was in situ generated via thiourea isomerization and then reacted with different amino groups (NH2 and NH) in tri-s-triazine rings to obtain two-type cyanamide defects. Theoretical calculations and experiment results confirm that the ratio of the two-type cyanamide defects could be adjusted by KCl dosage, accompanying tunable energy levels of CCN. The charge carrier transfer and separation of CCN was greatly improved. Furthermore, the existence of cyanamide defects hindered the formation of intermolecular hydrogen bonds among g-C3N4, which facilitated the formation of porous structure and exposed more active sites for photocatalytic hydrogen evolution reaction (HER). As a result, the optimized photocatalyst (CCN-0.03) showed a high HER rate of 4.0 mmol g−1h−1, which was 5 times higher than 0.8 mmol g−1h−1 for pristine g-C3N4. And the apparent quantum efficiency reached up to 14.65% at 420 ± 10 nm. The findings deepen the understanding on precise molecular tuning of g-C3N4.

NaCl Replacement with KCl Affects Lipolysis, Microbiological and Sensorial Features of Soppressata Molisana

The influence of partial replacement of NaCl with KCl on the lipolysis and on the microbial and sensory features of Soppressata molisana is investigated during 50 days of ripening. In addition, the relation between KCl and a multiple strain starter culture is also considered and the effects of their combination on some quality features are examined. The lipolysis, the microbiological and sensorial features and the lipid oxidation of experimental batches, are compared with those exhibited by control batches. The results highlight that the KCl, used as an alternative salt, is able to inhibit undesirable microorganisms equally to NaCl, ensuring the safety of the final products. In addition, a stimulating effect on the growth of added bacteria is detected in presence of KCl, with a resulting better fermentative process. In fact, the addition of KCl, even if produces a decrease in lipolytic activities, improves the nutritional value of soppressata molisana, in terms of higher PUFA/SFA ratio. These advantages are further amplified when the alternative salt is used in combination with the starter culture. Finally, the combined use of KCl and starter culture reduces the lipid oxidation and seems crucial for maintaining the sensorial features.Pratical Applications: The main findings of the present research highlight that the use of KCl in combination with an appropriately selected starter culture allows the production of healthier and safety dry‐fermented sausage (soppressata molisana) and consistent with WHO guidelines and modern consumers demand.Partial replacement of NaCl with KCl affects the behaviour of fermentative and lipolytic process in Soppressata molisana. KCl, in combination with a multiple strain starter culture, improves the nutritional features of dry‐fermented sausage by promoting lower SFA and higher MUFA and PUFA levels. Moreover, the innovative approach preserves sensorial features of traditional‐fermented sausages limiting lipid oxidation.

Effects of elctrolytes on the stability of wetting films: Implications on seawater flotation

Surface force measurements were conducted using the force apparatus for deformable surfaces (FADS) to better understand the stability of the wetting films formed on hydrophobic surfaces in the presence of KCl and MgCl2. The measurements were conducted using thiol-coated gold surfaces as robust model hydrophobic surfaces. The results obtained in pure water show that the wetting films of water on weakly hydrophobic surfaces are metastable due to the presence of a repulsive double-layer force in the films. At high concentrations of KCl, the wetting films become unstable due to double-layer compression, causing them to rupture. In the presence of MgCl2, both contact angles and hydrophobic forces decrease due to the adsorption of the hydrolysis products such as MgOH+ ions and Mg(OH)2 precipitates on the surface. The FADS data obtained in the present work were analyzed using the Frumkin-Derjaguin isotherm to determine the roles of the short- and long-range hydrophobic forces in determining the stability of the wetting films formed on hydrophobic surfaces. The results of the present study are discussed in view of the roles of electrolytes in seawater flotation.

Influence of KCl and HCl on high temperature corrosion of HVAF-sprayed NiCrAlY and NiCrMo coatings

The oxidation performance of NiCrAlY and NiCrMo coatings thermally sprayed by high velocity air-fuel (HVAF) technique has been investigated in a chloridizing-oxidizing environment, with and without a KCl deposit, at 600 °C for up to 168 h. Both coatings protected the substrate in the absence of KCl due to formation of a dense Cr-rich oxide scale. In the presence of KCl, Cl−/Cl2 diffused through a non-protective and porous NiCr2O4 scale formed on NiCrAlY, leading to formation of volatile CrCl3. On the other hand, Mo in NiCrMo stimulated the formation of a more protective Cr-rich oxide scale which increased the corrosion resistance by reducing Cl−/Cl2 diffusion.

C@TiO2 nanocomposites with impressive electrochemical performances as anode material for lithium-ion batteries

C@TiO2 nanocomposites as lithium-ion battery anode material have been synthesized through a typical solvothermal process. A series of characterization methods, such as scanning electron microscopy, field emission transmission electron microscopy, and X-ray photoelectron spectroscopy, has been used to determine the microstructures and chemical compositions of the C@TiO2 nanocomposites. The electrochemical performances were investigated by the LAND battery testing system and electrochemical workstation. Results showed that the size of the C@TiO2 nanoparticles is approximately 21–55 nm and the titanium dioxide (TiO2) nanoparticles are wrapped by the carbon layer containing an amount of graphitic carbon, of which the carbon source originated from the esterification reaction in the presence of KCl. An amount of graphitic carbon layers significantly ameliorated the electrical conductivity of the C@TiO2 nanocomposites and alleviated the volume expansion of TiO2 during the discharge–charge cycles, resulting in the C@TiO2 nanocomposites having a satisfactory reversible charge capacity of 237 mA h g−1 after 100 long cycles at the current density of 0.1 A g−1 and an impressive rate capability with the charge capacity of 176.5 mA h g−1 even at the high current density of 1.6 A g−1.

Catalytic behaviors of alkali metal salt involved in homogeneous volatile and heterogeneous char reforming in steam gasification of cellulose

The current study aimed to investigate catalytic behaviors of alkali metal salt participating in homogeneous steam-volatile and heterogeneous steam-char reforming reactions in steam gasification of cellulose. The results indicate that the temperature is a key parameter which significantly influenced both yield and composition of gas and tar and catalytic performances of KCl. Externally added steam had negligible effect on cracking/reforming of macromolecules volatiles at the temperature of 700 and 900 °C without KCl, whereas in the presence of KCl, it would be activated and further reacted with low reactivity macromolecules volatiles, leading to an increase in gas yield and a decrease in tar yield. KCl was notably involved in homogeneous steam-volatile reactions, and enhanced the water gas shift reaction and tar reforming reactions. However, KCl had little promotion effect on thermal cracking/reforming of levoglucosan in homogeneous steam-volatile reforming process at 500 °C. Its inhibition effect on levoglucosan formation mainly acted during the primary pyrolysis reactions. KCl could also enhance heterogeneous in situ char-steam reaction resulting in a higher H2 yield. The general pathway of KCl involved in homogeneous/heterogeneous reactions in steam gasification of biomass was eventually proposed.

Control of Aliivibrio fischeri Luminescence and Decrease in Bioluminescence by Fungicides.

Studies have reported that cell density, ultraviolet (UV) irradiation, and redox reactions, can induce bioluminescence in bacteria. Conversely, the relationship between seawater components and luminescence is not well understood. The efficacy of marine luminous bacteria as biosensors, and their reactivity to fungicides (for example postharvest pesticides) are also unknown. Therefore, we studied the relationship between the luminescence of Aliivibrio fischeri and the composition of artificial seawater media and analyzed the toxicity of fungicides using A. fischeri grown only with the elements essential to induce luminescence. Luminescence was activated in the presence of KCl, NaHCO3, and MgSO4. In addition, we cultivated A. fischeri with other compounds, including K+, HCO3-, and SO42- ions. These results suggested that A. fischeri requires K+, HCO3-, and SO42- ions to activate cell density-independent luminescence. Additionally, A. fischeri cultured in 2.81% NaCl solutions containing KCl, NaHCO3, and MgSO4 exhibited a decrease in luminescence in the presence of sodium orthophenylphenol at >10 ppm. This result suggests that A. fischeri can be used as a biosensor to detect the presence of sodium ortho-phenylphenol.

Sulfamethoxazole induces zinc changes at hippocampal mossy fiber synapses from pregnant rats.

The accumulation of intracellular ionic zinc and pharmaceutical compounds, like the antibiotic sulfamethoxazole, may contribute to various neuropathologies. Sulfamethoxazole and the drug trimethoprim, are inhibitors of enzymes involved in the synthesis of tetrahydrofolate and also of carbonic anhydrases. The inhibition of the latter enzymes, which are localized both intra- and extracellularly and have a key role in pH regulation, causes alkalinization that is associated with higher spontaneous transmitter release. Intense synaptic stimulation causes the entry of released zinc into postsynaptic neurons, through glutamate receptor channels or voltage dependent calcium channels. The aim of this study was to evaluate the effect of sulfamethoxazole (180 μM) on basal postsynaptic zinc and to compare it with that caused by two depolarizing media, containing high potassium or tetraethylammonium, which may induce long term synaptic plasticity. The studies were performed in brain slices from gestating rats, at the mossy fiber synapses from hippocampal CA3 area, using the zinc indicator Newport Green. In the presence of KCl (20 mM) and sulfamethoxazole (180 μM) the zinc signals were enhanced, unlike in tetraethylammonium (25 mM). After sulfamethoxazole the tetraethylammonium evoked zinc signal had reduced amplitude. Thus, the data suggests that sulfamethoxazole enhances transmitter release affecting synaptic zinc physiology.

Multiple Thermal Gelation of Hydroxypropyl Methylcellulose and Kappa-Carrageenan Solutions and their Interaction with Salts

The multiple gelation behavior of aqueous solutions of kappa-carrageenan (KCG) and low molecular weight hydroxypropyl methylcellulose (HPMC) was studied with the presence of various salts. Multiple gelation behavior of aqueous solutions of HPMC/KCG/salt mixture were found. The shear viscosity of HPMC/KCG blend increased by one orders of magnitude, while the viscosity of HPMC/KCG/potassium chloride (KCl) mixture increased by three orders of magnitude as compared to HPMC solution at temperatures below apparent gelation. The dynamic elastic modulus of HPMC/KCG blend increased by two orders of magnitude, while the elastic modulus of HPMC/KCG/potassium chloride (KCl) mixture increased by three orders of magnitude as compared to HPMC solution at temperatures below apparent gelation temperature. The gel elastic modulus of the solution blend of HPMC/KCG/salt mixture decreased in the order of KCl > NaCl > CaCl2. Thermal analysis revealed a linear relationship between the depression of melting temperature and the salt concentrations, which is independent of KCG. The free water content computed by enthalpy data showed that free water content decreased with increasing salt concentrations. The secondary peak which typically associated with bound water appeared in the mixture of HPMC and KCG in the presence of KCl. As the concentrations of KCl salt increased, the bound water peak also amplified and lifted to a higher temperature.

Extracellular acidosis selectively inhibits pharmacomechanical coupling induced by carbachol in strips of rat gastric fundus.

What is the central question of this study? Acute acidosis that results from short-term exercise is involved in delayed gastric emptying in rats and the lower responsiveness of gastric fundus strips to carbachol. Does extracellular acidosis decrease responsiveness to carbachol in tissues of sedentary rats? How? What is the main finding and its importance? Extracellular acidosis inhibits cholinergic signalling in the rat gastric fundus by selectively influencing the Gq/11 protein signalling pathway. Acute acidosis that results from short-term exercise delays gastric emptying in rats and decreases the responsiveness to carbachol in gastric fundus strips. The regulation of cytosolic Ca2+ concentrations appears to be a mechanism of action of acidosis. The present study investigated the way in which acidosis interferes with gastric smooth muscle contractions. Rat gastric fundus isolated strips at pH6.0 presented a lower magnitude of carbachol-induced contractions compared with preparations at pH7.4. This lower magnitude was absent in carbachol-stimulated duodenum and KCl-stimulated gastric fundus strips. In Ca2+ -free conditions, repeated contractions that were induced by carbachol progressively decreased, with no influence of extracellular pH. In fundus strips, CaCl2 -induced contractions were lower at pH6.0 than at pH7.4 but only when stimulated in the combined presence of carbachol and verapamil. In contrast, verapamil-sensitive contractions that were induced by CaCl2 in the presence of KCl did not change with pH acidification. In Ca2+ store-depleted preparations that were treated with thapsigargin, the contractions that were induced by extracellular Ca2+ restoration were smaller at pH6.0 than at pH7.4, but relaxation that was induced by SKF-96365 (an inhibitor of store-operated Ca2+ entry) was unaltered by extracellular acidification. At pH6.0, the phospholipase C inhibitor U-73122 relaxed carbachol-induced contractions less than at pH7.4, and this phenomenon was absent in tissue that was treated with the RhoA kinase blocker Y-27632. Thus, extracellular acidosis inhibited pharmacomechanical coupling in gastric fundus by selectively inhibiting the Gq/11 protein signalling pathway, whereas electromechanical coupling remained functionally preserved.

Tocotrienols Stimulate Insulin Secretion of Rat Pancreatic Isolated Islets in a Dynamic Culture.

Tocotrienols (T3) are the naturally occurring vitamin E derivatives that possess antioxidant properties and therapeutic potential in diabetic complications. The bioactivities of the derivatives are determined by the number and arrangement of methyl substitution on the structure. The objective of this study was to determine the effects of T3 derivatives, σ-T3, γ-T3 and α-T3 on insulin secretion of rat pancreatic islets in a dynamic culture. Pancreatic islets isolated from male Wistar rats were treated with T3 for 1 h at 37°C in a microfluidic system with continuous operation that provided a stable cell culture environment. Glucose (2.8 mM and 16.7 mM, as basal and stimulant, respectively) and potassium chloride (KCl) (30 mM) were added to the treatment in calcium free medium. The supernatant was collected for insulin measurements. Short-term exposure (1 h) of σ-T3 to β cells in the stimulant glucose condition significantly potentiated insulin secretion in a dose-dependent manner. γ-T3 and α-T3 also displayed dosedependent effect but were less effective in the activation of insulin secretion. Essentially, KCl, a pancreatic β cell membrane depolarizing agent, added into the treatment further enhanced the insulin secretion of σ-T3, γ-T3 and α-T3 with ED50 values of 504, 511 and 588 µM, respectively. The findings suggest the potential of σ-T3 in regulating glucose-stimulated insulin secretion (GSIS) in response to the intracellular calcium especially in the presence of KCl.

Salt-Induced Aggregation of Negatively Charged Gold Nanoparticles Confined in a Polymer Brush Matrix

We report on the salt-induced aggregation of citrate-coated gold nanoparticles (AuNPs) confined within poly(N-isopropylacrylamide) (PNIPAM) brushes grafted from flat substrates. Compared to highly dispersed AuNPs, a red-shift and broadening of the surface plasmon (SP) band is observed when the AuNPs are confined by the PNIPAM brush matrix due to their close vicinity. Additional red-shifting and broadening occur upon immersion in aqueous salt solutions (1 M NaF, NaCl, NaBr, and KCl). Nanoparticle assemblies are established due to salt-induced aggregation of AuNPs and are dependent on the type of salt. In the presence of KCl, nanoparticle assemblies are built up that result in the formation a second plasmon peak at ∼700 nm. The color change of PNIPAM/AuNP is associated with (1) the collapse of the PNIPAM brushes in the presence of salt and (2) nanoparticle aggregation due to electrostatic screening of the negative charges around the AuNPs by the salt ions. Ion specificity is related to ion-pair association ...

Regulation of structure, rheological and surface properties of chitin nanocrystal dispersions

The hydrosols of chitin nanocrystals (ChN) are promising as modifiers of properties, drug delivery systems, and media. The purpose of this work is to clarify the mechanisms for regulating processes of stability and structure formation occurring in the ChN hydrosols under the influence of varying ionic strength. ChN were isolated from the crab shell; ChN hydrosols are obtained with different concentrations of the dispersed phase. The structure and morphology of the particles was studied by atomic force microscopy and X-ray diffraction. Hydrosols were studied by rotational viscometry, dynamic light scattering, and photometry in the presence of KCl with concentration up to 200mM. The experimental results of finding the rapid coagulation threshold are compared with calculated ones performed with the use of the modified DLVO theory. It is established that in the range of electrolyte concentrations 30∼75mM, the optical and rheological properties of the ChN hydrosols undergo crucial changes. At an electrolyte concentration of 20∼150mM, particles coagulate at a secondary potential minimum; the parallel orientation of the particles is energetically more advantageous. In systems with a higher concentration of electrolyte, there is no potential barrier; rapid barrier-free coagulation is observed, with the formation of stronger coagulation contacts and the formation of stable gels.

Periodic precipitation of cobalt hydroxide in agar gel: Effect of ionic strength

The present paper highlights the effect of ionic strength due to addition of potassium chloride (KCl) in a diffusing medium on the periodic precipitation (Liesegang patterns) of CoCl2+ NH4OH system. The patterns are obtained by addition of known amount of KCl in an agar gel medium in a glass tube. In the absence of KCl, the precipitating system exhibits a common trend of increase in spacing between consecutive bands with the movement of outer electrolyte towards the lower boundary of the tube thus maintaining constant value of spacing coefficient. However it was observed that the addition of KCl causes decrease in the value of spacing coefficient. The presence of KCl also results in a marked deviation in the width and the time of formation of the precipitating rings. Periodicity of the precipitation pattern is lost and continuous precipitation is obtained in the presence of excess KCl.

Structure and oil responsiveness of viscoelastic fluids based on mixed anionic/cationic wormlike surfactant micelles

In this work, a combination of small-angle neutron scattering, dynamic light scattering and rheometry was applied in order to investigate the structure and oil responsiveness of anionic/cationic wormlike surfactant micelles formed in a mixture of potassium oleate and n-octyltrimethylammonium bromide (C8TAB). A new facile method of calculating the structure factor of charged interacting wormlike micelles was proposed. It was shown that the mean distance between the micelles decreases upon the increase of the amount of cationic co-surfactant and lowering of the net micellar charge. It was demonstrated that highly viscous fluids containing mixed anionic/cationic wormlike micelles are highly responsive to oil due to its solubilization inside the micellar cores, which leads to the disruption of micelles and formation of microemulsion droplets. Experimental data suggest that solubilization of oil proceeds differently in the case of mixed anionic/cationic micelles in the absence of salt, and anionic micelles of the same surfactant in the presence of KCl.

Laser Clad and HVOF-Sprayed Stellite 6 Coating in Chlorine-Rich Environment with KCl at 700\xa0\xb0C

Laser clads and HVOF coatings from a stellite 6 alloy (Co–Cr–W–C alloy) on 304 stainless steel substrates were exposed both bare and with KCl deposits in 500 ppm HCl with 5% O2 for 250 h at 700 °C. SEM/EDX and PXRD analyses with Rietveld refinement were used for assessment of the attack and for analysis of the scales. The bare samples suffered from scale spallation and the scale was mostly composed of Cr2O3, CoCr2O4 and CoO, although due to dilution haematite (Fe2O3) was detected in the scale formed on the laser clad sample. A small amount of hydrated HCl was detected in bare samples. While the corrosion of the bare surfaces was limited to comparatively shallow depths and manifested by η and M7C3 carbide formation, the presence of KCl on the surface led to severe Cr depletion from the HVOF coating (to 1 wt%). Both inward and outward diffusion of elements occurred in the HVOF coating resulting in Kirdendall voids at the coating–steel interface. The laser clad sample performed significantly better in conditions of the KCl-deposit-induced corrosion. In addition to the oxides, CoCl2 was detected in the HVOF sample and K3CrO4 was detected in the laser clad sample. Thermodynamic calculations and kinetic simulations were carried out to interpret the oxidation and diffusion behaviours of coatings.