The eco-friendly and cost-efficient synthesis of polyaniline (PANI) is one of the perplexing tasks in the research horizons of conducting polymers while keeping the desired properties unaffected. The present work reports an eco-friendly and comparably cost-efficient pathway for the synthesis of corrosion-resistant, thermally stable, and highly soluble PANI salt using coconut oil as a novel dispersion medium. The PANI salt was optimized by varying the reaction parameters, such as concentration of monomer, oxidant, surfactant, and solvent. The UV/Visible spectra indicated absorption peaks in the range of 344-353, 424-433, and 740-779 nm. The FTIR analysis of PANI salt reveals the stretching of the benzenoid and quinoid rings at 1460 and 1559 cm-1respectively. Xray diffraction shows peaks on 2? at 19? and 25? which are the characteristic peaks of PANI. PANI salt was found to be soluble in several organic solvents such as 2-propanol, n-Methylpyrolidinone (NMP), and highly soluble in chloroform and Dimethyl sulfoxide (DMSO) up to 7.6 and 6.9% respectively. SEM images and TGA analysis of PANI confirmed the porous morphology like cauliflower and quite thermally stable up to 538 ?C respectively. The layer of synthesized PANI shows remarkable corrosion inhibiting behavior on the surface of mild steel which reduces the rate of corrosion up to 82%. Hence, boost up the global economy.