Abstract
Corrosive processes in acidic medium reduce the performance and durability of metallic materials, causing problems to several industries. Corrosion inhibitors are commonly used to decrease these effects. As these inhibitors must be ecologically friendly currently, this work evaluated the anticorrosive effect of natural extracts of coffee husks (Coffea arabica L.) in the protection of carbon steel in 1 mol L-1 HCl solution. Extractions were performed using water as the extraction solvent. The polyphenols content increased with the extraction temperature, and the extracts were produced using 100 oC. Extract concentrations of 10, 20 and 30 % v/v were analyzed as inhibitors for carbon steel in acid medium, using weight loss and electrochemical tests, as well as scanning electron microscopy. There was an increase in the inhibition efficiency as the extract concentration increased, reaching values around 97 % using 30 %v/v of extract for the weight loss tests.
Highlights
The most widely reported concepts of corrosion are defined as the deterioration of a metallic or non-metallic material, or as the deterioration of the properties of these materials by chemical or electrochemical action of the environment to which they are exposed to[1]
The present result suggests that 100 oC is the best working temperature to produce coffee husks inhibitory extracts, as more polyphenolic compounds were released under this condition
A smoother surface can be noted when the specimen was immersed in the corrosive medium containing the natural extract (Figure 7C). These results indicate that the steel surface was protected by the inhibitory extract, which is in agreement with the electrochemical and weight loss results previously presented
Summary
The most widely reported concepts of corrosion are defined as the deterioration of a metallic or non-metallic material, or as the deterioration of the properties of these materials by chemical or electrochemical action of the environment to which they are exposed to[1]. The reaction processes that trigger corrosion are spontaneous, presenting a chemical or electrochemical feature, and tend to modify the physical-chemical characteristics of the materials. Due to the increased environmental awareness, the need to develop environmentally friendly processes has been focused on the corrosion inhibiting properties of natural products[4,5]. This area of research has great importance because, besides of being ecologically sound, non-toxic and mostly biodegradable, agro-industrial products are sources of cheap, readily available, and renewable materials[4,5,6]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.