Strobilanthes crispus (black face general) extract as an eco-friendly inhibitor for aluminum corrosion in acidic medium / Muhammad Akmal Syauqi Bin Mohammad Fauzan

Faculty of Chemical and Process Engineering Technology

Final Year Report (Bachelor of Chemical Engineering Technology (Hons) ) -- Universiti Malaysia Pahang Al-Sultan Abdullah - 2024

Include bibliographical reference

Implementation of corrosion has been a game-changer for skilled and practical preventive measures against corrosion, a prevalent problem in different industries but especially in the oil and gas sector, where it causes material degradation, economic losses and safety threats. This study analyze the possibilities of Strobilanthes crispus methanolic extract as an eco-friendly corrosion inhibitor. Strobilanthes crispus leaves were dried, grinded to fine powder and extracted with Soxhlet apparatus for methanol as solvent. Successfully isolated bioactive compounds from it, such as alkaloids, phenols, flavonoids, terpenoids, and tannins, that are usually believed to have some anticorrosive properties. FTIR spectroscopy was performed to identify the functional groups responsible for the damping performance of the extract. The FTIR spectrum exhibited distinct peaks, like N-H stretching (3300-3500 cm), which indicates the existence of primary amines, and C-H stretching (2800-3000 cm), which confirms the existence of saturated hydrocarbons. Other major functional groups such as O-H stretching (3200-3500 cm-") and C=0 stretching (1630-1750 cm) were also linked with the presence of phenols, flavonoids and terpenoids. These functional groups contribute to effective corrosion inhibition mechanisms, such as adsorption on to metal surfaces, formation of hydrophobic protective films, chelation with metal ions and antioxidant activity. This includes the electrolyte solution and chloride ions that leads to corrosion by forming a protective layer that blocks corrosive elements from making contact with the metal surface. Hydrocarbons help in forming hydrophobic coatings while the amines and phenols interact chemically or physically with the substrate surface. Flavonoids and tannins further stabilize the protective barrier by chelating metal ions and reducing the oxidative stress on the surface by neutralizing reactive oxygen species. This study strongly recommends the use of Strobilanthes crispus methanolic extract as a green and sustainable corrosion inhibitor. This study not only addresses the global problem of cytotoxicity and provides improved anticancer drug-like substances but also caters to the increasing demand for natural alternatives to the traditional synthetic inhibitors by exploiting bioactive compounds from plants. The results lay the foundation for in-depth studies on the tailoring of extraction methods and the potential industrial applications of Strobilanthes crispus extracts, especially in the oil and gas sector.