Rajesh Haldhar

Investigation of corrosion inhibition effect and adsorption activities of Cuscuta reflexa extract for mild steel in 0.5 M H2SO4

The corrosion inhibition nature of Cuscuta reflexa fruit extract, belonging to the family of Piperaceae, has been analyzed on mild steel in 0.5 M H2SO4 with the help of weight loss studies, potentiodynamic polarization, and electrochemical impedance spectroscopy techniques. The C. reflexa extract contains 3‑methoxy‑3,4,5,7‑tetrahydroxy flavone, which decreases the corrosion rate of mild steel in acidic medium. The maximum corrosion inhibition efficiency was observed at 500 mg/L inhibitor concentration. The adsorption study of C. reflexa extract on mild steel surface has been conducted using UV, FTIR, AFM, SEM, and DFT.

Valeriana wallichii root extract as a green & sustainable corrosion inhibitor for mild steel in acidic environments: experimental and theoretical study

Corrosion inhibition analysis and the adsorption behaviour of Valeriana wallichii root extract for mild steel in 0.5 M H2SO4 solution has been investigated utilizing weight loss, electrochemical impendence spectroscopy (EIS), potentiodynamic polarization, SEM, AFM UV-visible spectroscopy, FT-IR, and quantum chemical calculations. Both the electrochemical and weight loss estimations indicated that the root extract of Valeriana wallichii shows excellent inhibition performance of up to 93.47% for mild steel at 500 mg L−1 concentration in 0.5 M H2SO4 solution at 298 K. Naphthoic acid, iridoid and an iridoid analogue are the major phytochemical constituents in the extract of Valeriana wallichii, which possess oxygen atoms (lone pair electrons) and π electrons that facilitate adsorption onto the metal surface. The adsorption of this extract obeys the Langmuir adsorption isotherm. Polarization investigations confirmed that the root extract of Valeriana wallichii acts as a mixed type of inhibitor. The surface studies confirm corrosion retardation in the presence of the extract due to the formation of a protective layer on the surface of mild steel.

Natural non poisonous green inhibitor of Glycyrrhiza glabra for mild steel in 3.5% NaCl

Leaves extracts of Glycyrrhiza glabra was investigated as sustainable corrosion resister of mild steel in 3.5% NaCl by using polarization measurements, UV, IR and SEM study. This plant shows good corrosion inhibition efficiency at lower concentration of inhibitor. This plant extract act as a mixed type of inhibitor and form a defensive coat on the surface of mild steel and decreases the corrosion rate. Here, our main goal to find out the corrosion barricade characters of the plant extract saturated with 3.5% NaCl.