Characterization of metal corrosion by aqueous amino acid salts for the capture of CO₂

We investigated the absorption ability of potassium salts of amino acid solutions for carbon dioxide and compared the results with MEA. The corrosion and degradation behavior were investigated in a CO₂ absorption process using aqueous potassium salts of glycine and taurine. The experimental parameters varied were the concentration, amino acid type, temperature, CO₂ loading, piperazine, and the presence of corrosion inhibitors. The corrosion characteristics of carbon steel were measured with potassium glycinate and potassium taurate solutions over a wide range of concentrations (1.5 to 5.0 M) and temperatures (313.15 to 353.15 K). The corrosion rate was calculated using a weight loss method averaging the results of four specimens. The experimental results indicate that increases in the concentration of the aqueous amino acid salts, solution temperature, CO₂ loading, and piperazine concentration accelerate the corrosion rate. In addition, corrosion inhibitors were proven to be effective in controlling corrosion.