gradually changed,owing to the growing interest and attention of the world towards
environmental problemsprotecting the environment, and the hazardous effects of using
chemicals on the ecologicalbalance. Toxic inhibitors that are widely used during
industrial processes should be replacedwith new environmentally friendly inhibitors.
The anticorrosion performance of plant-based antioxidants has gained
importance; hence, the anticorrosive effect of 2-propanol APE on carbon steel was
evaluated. Inhibitor effectiveness of the apricot pomace extract as a vapor phase
inhibitor of atmospheric corrosion of steel was evaluated with the method of
accelerated tests under condition of condensation of moisture [10-12].
Fig. 4 represents inhibition efficiency (IE, %) values obtained from the weight
loss in conditions of periodic condensation of moisture after period of film-forming in
the presence of different concentrations of apricot pomace extract. Clearly, inhibition
efficiency increases with an increase of the inhibitor concentration, i.e. the corrosion
inhibition enhances with the inhibitor concentration.
The increase of the inhibition efficiency in the presence of the SAM shows more
APE molecules were adsorbed on the steel surface at the higher concentration of APE.
At 80 mg l
-1
, the maximum IE is 92.60% for apricot pomace extract, which indicates
that all compounds act as moderate corrosion inhibitors for steel.
Figure 4. Relationship between inhibition efficiency and concentration of
inhibitor in the conditions of periodic condensation of moisture for 21 days (weight
loss method, pre-treatment immersion time 48 h).
SEM images of the surface after accelerated trials are shown in Fig. 5. As shown
in Fig. 5, the steel sample appeared to be smooth and without any visible traces of
corrosion products, due to the formation of a protective inhibitor layer on the metallic
surface, which retarded the dissolution process.
In analyzing the influence of VIAC films on the rate of the partial electrode
processes of anodic oxidation of steel and cathodic reduction of the molecular
atmospheric oxygen in a 0.5 М Na
2
SO
4
solution with and without protective films, it
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