Phytochemical screening and inhibitive potential of halide ions and plant extracts of Cassia occidentalis leaves as corrosion inhibitor of mild steel in sulphuric acid medium

The crude extract of Cassia occidentalis leaves was used in this study to screened the phytochemicals and examine its inhibitory qualities as a corrosion inhibitor for mild steel in 1M sulphuric acid media. The phytochemicals showed the existence of alkaloids, glycosides, flavonoids, carbohydrates, tannins, saponins, phenols, and steroids. Flavonoids make up the majority of the extract, with alkaloids coming in second where anthraquinolones, proteins, and amino acids are absent. Weight loss was used to investigate mild steel corrosion inhibition in 1M sulphuric acid media. The inhibitory effectiveness of Cassia occidentalis extracts rise with concentration and at a low temperature. The inhibitor's maximum efficiency was 70% after three hours of immersion at a concentration of 0.7 g/L extract. The results showed that Cassia occidentalis extracts effectively inhibited mild steel corrosion, and that the presence of halide ions increased the inhibition's effectiveness. The order of the halide ions' synergistic action was KI >KBr >KCl. Extracts from Cassia occidentalis shows an inhibitory impact due to the extract components' adsorption on the mild steel surface. The corrosion process is exothermic and spontaneous. The corrosion reaction's activation energy is raised when the leave extracts is present.The results of a study using scanning electron microscopy to examine the surface morphology of mild steel in inhibited and uninhibited acid solutions revealed that the presence of extract and halide inhibitors remarkably lowers the corrosion rate. This is as a result of the extract and halide inhibitor molecules adhering to the surface and forming a barrier that prevents an acid attack.