Abstract: Panatx notoginseng extractive (PNE) achieved by immersion was investigated as a corrosion inhibitor for Q235 steel in 1 mol·L^-1 HCl solution by means of the weight loss and electrochemical methods, with a view to providing experimental bases for the development and utilization of plant-type pickling corrosion inhibitors. The results showed that PNE could retard the rate of metal corrosion reaction, and belongs to mixed-type inhibitor in mechanism. The corrosion inhibition performance for PNE is positively correlated with its own concentration, which becomes weaker with the increase of test temperature. The adsorption of PNE molecules conforms to the Langmuir equation, and leads to the elevation of activation energy of the corrosion reaction and then reduces the reaction rate.

Key words: Q235 steel, Panatx notoginseng extractive (PNE), adsorption, inhibition