Psidium guajava Leaves as Corrosion Inhibitor of Al-6061

The anti-corrosion characteristic of the extract of Psidiumguajava leaves on aluminum in 3.5 wt% sodium chloride were examined using electrochemical measurement. The thermodynamic factors such as the free energy adsorption, change in enthalpy, and entropy was also analyzed. The adsorption isotherm was detail described to study the adsorption of the inhibitor on the aluminum surface with various concentrations of the inhibitor. The electrochemical measurement was done through the potentiodynamic polarization test. The results show that the inhibitor act as the mixed type inhibitor and its adsorption on the aluminum surface obeys Temkin adsorption isotherm. The study suggests that the use of Psidium guajava leaves extract for the food industrial application is eco-friendly and safe, especially in salt solution medium.

L-Proline as a Green Corrosion Inhibitor in Aqueous Solutions for Carbon Steel

The chemical technique was used to investigate the inhibition and adsorption properties of L-proline for steel corrosion (weight loss method). As the concentration of L-proline increased, the inhibition efficiency increased, but decreased as the temperature increased, according to the findings. The inhibitor’s adsorption to the steel surface has been shown to be random, involving both electrostatic and chemisorptions. The Temkin adsorption isotherm governs the adsorption of L-proline to the steel surface. Thermodynamic parameters have been determined in some cases.

Anti-Corrosive Effect of Jordanian-Bay- Leaves Aqueous Extract on Mild Steel in 1.0 M Hydrochloric Acid Solution

Natural inhibitors are the most crucial manner to lessen the corrosion price of various business metals. There are several strategies being used with corrosion inhibitors. One technique being used is the Electrochemical strategies. The gain with this technique is their brief size time and mechanistic information. It is beneficial in the corrosion's layout safety techniques besides the layout of the brand new inhibitors, there are 3 styles of corrosion inhibitors as anodic inhibitors, cathodic inhibitors, over one inhibitor. The corrosion inhibition of slight metallic in 1.0 M HCl solution with the aid of using Jordanian -Bay- leaves extract has been studied with the use of potentiodynamic polarization technique. Results received a display that Bay- leaves aqueous extract behaves as an anodic inhibitor for slight metallic in 1.0 M HCl solution. The inhibitor capabilities thru adsorption following Temkin adsorption isotherm. The impact of parameters like temperature and inhibitor awareness at the corrosion of slight metallic has additionally been studied.

Anti-Corrosive Effect of Jordanian-Bay- Leaves Aqueous Extract on Mild Steel in 1.0 M Hydrochloric Acid Solution

Natural inhibitors are the most crucial manner to lessen the corrosion price of various business metals. There are several strategies being used with corrosion inhibitors. One technique being used is the Electrochemical strategies. The gain with this technique is their brief size time and mechanistic information. It is beneficial in the corrosion's layout safety techniques besides the layout of the brand new inhibitors, there are 3 styles of corrosion inhibitors as anodic inhibitors, cathodic inhibitors, over one inhibitor. The corrosion inhibition of slight metallic in 1.0 M HCl solution with the aid of using Jordanian -Bay- leaves extract has been studied with the use of potentiodynamic polarization technique. Results received a display that Bay- leaves aqueous extract behaves as an anodic inhibitor for slight metallic in 1.0 M HCl solution. The inhibitor capabilities thru adsorption following Temkin adsorption isotherm. The impact of parameters like temperature and inhibitor awareness at the corrosion of slight metallic has additionally been studied.

Citrus sinensis Extract as a Green Inhibitor for the Corrosion of Carbon Steel in Sulphuric Acid Solution

Citrus sinensis extract is considered a good inhibitor to protect the carbon steel in half of molar of sulfuric acid from corrosion, as it was found from the results of chemical methods such as the weight loss (ML) method and also from the results of electrochemical methods such as potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM). The polarization curves indicated that this extract acts as a mixed kind inhibitor. The adsorption of this extract on the carbon steel surface is of mixed type physisorption and chemisorption, but chemisorption is the most effective one and followed Temkin adsorption isotherm. Several tests have proved a layer that protects carbon steel from corrosion.

Corrosion Inhibition of Brazing Cu-Ag Alloy with 1,2,3-Benzotriazole and 2,5-Dimercapto-1,3,4-Thiadiazole

Adsorption and inhibition behavior of 1,2,3-benzotriazole (BTA) and 2,5-dimercapto-1,3,4-thiadiazole (DMTD) on brazing Cu-Ag alloy was studied in deionized water using potentiodynamic polarization measurement, adsorption isotherm investigation and X-ray photoelectron spectroscopy (XPS). Pure Ag and pure Cu were included to investigate the mere effect of each component on the alloy’s behavior. Results show better inhibition of DMTD for Ag and BTA for Cu, both by chemisorption. BTA was found to follow Langmuir isotherm while DMTD obeyed Temkin adsorption isotherm, despite both acting as a mixed type inhibitor. Combining the two inhibitors increased the inhibition efficiency over 80% for the Cu-Ag alloy. XPS spectra demonstrate the formation of DMTD protective film through DMTD’s functional groups of pyrrolic N from the azole ring and thiol S from the mercapto anchoring group on Ag and thiol S on Cu. Compared to BTA, the higher affinity of DMTD to Ag was attributed to the involvement of two heteroatoms with the Ag surface.

Adsorption Behavior of some N-alkyl Pyridinium Salts from Aqueous Solution on Amberlite-IR 120 H+ resin

The effect of Amberlite-IR 120 H+ resin to remove some organic compounds (N-alkyl pyridinium salts) from aqueous solutions at certain conditions was investigated. The effect of resin dosage, contact time, adsorbate concentration, ionic strength and solution temperature on the adsorption efficiency was examined. The experimental data collected generally proved that the adsorption efficiency decreased as the alkyl chain increased. The thermodynamic equilibrium parameters of the adsorption processes were evaluated and showed that the adsorption process is spontaneous, disordered and exothermic. Langmuir, Freundlich, Temkin and Dubinin–Radushkevich (D.R) isotherm models were applied based on the batch method. Freundlich, Temkin and D. R gave bilinear segments model based on the adsorbate initial concentrations except that for compound III where it gave straight of one segment for Temkin adsorption isotherm. Overall, Amberlite-IR 120 H+ resin is effective in removing some N-alkyl pyridinium salts from an aqueous solution.

Kinetic, isotherm and thermodynamics investigation on adsorption of divalent copper using agro-waste biomaterials, Musa acuminata, Casuarina equisetifolia L. and Sorghum bicolor

Three novel and distinct agricultural waste materials, viz., Casuarinas fruit powder (CFP), sorghum stem powder (SSP) and banana stem powder (BSP) were used as low cost adsorbents for the removal of toxic copper(II) from aqueous solutions. Acid treated adsorbents were characterized by SEM, EDX and FTIR. Different factors effecting adsorption capacity were analyzed and the efficiency order was BSP>SSP>CFP. Based on the extent of compatibility to Freundlich/Langmuir/D-R/Temkin adsorption isotherm and different models (pseudo-first and second order, Boyd, Weber’s and Elovich), chemisorption primarily involved in the case of CFP and SSP, whereas, simultaneous occurrence of chemisorption and physisorption was proposed in the case of BSP. Based on the observations, it was proposed that three kinetic stages involve in adsorption process viz., diffusion of sorbate to sorbent, intra particle diffusion and then establishment of equilibrium. These adsorbents have promising role towards removal of Cu(II) from industrial wastewater to contribute environmental protection.

Bee Wax Propolis Extract as Eco-Friendly Corrosion Inhibitors for 304SS in Sulfuric Acid

The inhibition properties of bee wax propolis (BWP) extract on the 304SS in 0.5 M sulfuric acid were conducted using potentiodynamic polarization, EIS, and XRD. Quercetin (2-(3.4-dihydroxy phenyl)-3.5.7-trihydroxy-4H-chromen-4-one) was identified as the main compound in the BWP extract based on FTIR and HPLC analysis. The results showed that the inhibitor could retard the corrosion rate of 304SS in 0.5 M sulfuric acid which reached 97.29% and 91.42% at 2000 ppm based on potentiodynamic polarization and EIS measurement, respectively. The inhibition efficiency decreased with increasing temperature. The inhibition mechanism of BWP extract on the 304SS was physisorption and obeyed Temkin adsorption isotherm equation. The thin protective layer on the 304SS surface was confirmed by XRD.