Mangsat, Aubrey Janine V.

Utilization of ethanol extract of chayote ( Sechium edule) peels for corrosion inhibition on iron nails/ Aubrey Janine V. Mangsat, Sheryl Mae A. Masamoc, Grace B. Piliotas, and Onisifura P. Reyes .-- - Manila: Technological University of the Philippines, 2023. - viii, 106pages: 29cm. +1 CD-ROM (4 3/4in.)

Thesis (undergraduate)

College of Science .--

Includes bibliography.

Metal corrosion is caused by the oxidation of atoms on the surface, resulting in
irreparable damage to the metal constructions at startling expenses. This encourages the
development of an alternative corrosion inhibitor that is cost-effective and environmentally
friendly, including chayote peels. Chayote peels were extracted in three methods: (1) dried
leaves with ethanol, addition of HCl, then reflux, (2) soaking of dried leaves with ethanol
and HCl, then reflux, (3) soaking of dried leaves with HCl and water, then reflux. The
extracts obtained following the three methods were phytochemically screened, and the
results showed that they contain tannins, flavonoids, terpenoids, saponins, alkaloids, and
glycosides. Among the three methods, extract from method 2 possessed more active
phytochemicals containing -OH, C-H, C=C, and C-O based on the FTIR analysis. Results
also showed that it has the greatest inhibition efficiency of 98.79%. Evaluation using Gas
Chromatography-Mass spectroscopy revealed that extract produced by method 2 contains
13 major compounds, including fatty acid ester, the most abundant compound. Ferroxyl
indicator test was done, and the result portrayed that corrosion is inhibited in nails soaked
in chayote peel extract. For surface examination under light microscope, iron nails soaked
in acidic solution without extracts have rough surface while iron nails soaked in acidic
solution with extract have smooth surface, this confirms that the chayote peel extract
inhibits corrosion on iron’s surface. Nails soaked in 5% extract showed no significant
amount of corrosion even after 9 days. Results revealed that the extract from chayote peel
is an effective corrosion inhibitor.


Ethanol extraction
Chayote peels

BTH RB 37 / M36 2023