68-74The newly synthesized quaternary ammonium salt, 1, 4-Bis (dimethyl decyl) ethylene diammonium bromide has been
characterized by FT-IR, 1H NMR, 13C NMR. It has been examined for its corrosion efficiency by the weight loss method by
immersing in a 1M HCl solution. The surface morphology is characterized using Scanning Electron Microscopy and it
exhibited the variation between corroded surface and inhibited surface of carbon steel.Energy-Dispersive X-ray
spectroscopy also shown the differences in composition of the corroded and surface coated with inhibitor. The efficiency of
the inhibitor is investigated by varying the concentration of the inhibitor from 100 to 500 ppm and over a temperature range
from 25 to 45C. Inhibitor efficiency is maximum in the concentration range of 500 ppm and found to be 77.75% at 45C.
The plot of concentration against surface coverage revealed that, the present system follows Langmuir’s adsorption
isotherm. Compared to acidic medium, inhibitor excelled its maximum efficiency in the neutral medium