Amino Acids

Salts of amino acids have been used for acid gas removal since the 1930s, mostly in Europe and especially in Germany for applications including refinery, natural gas and coke oven gas, a very challenging application because of corrosion and the presence of oxygen. These early solvents used the potassium salts of N,N-dimethylaminoacetic acid and N-methylalanine, the so-called ALKAZID® solvents developed by I. G. Farbenindustrie in the early 1930s.  They are very robust solvents, resistant to environments that would quickly degrade conventional amines and that exhibit zero volatility, eliminating vaporization losses.

Within the last several years, interest has developed in using the sodium or potassium salt of glycine (NaGly), the simplest primary amino acid, for CO₂ capture. Another proposal (Wagner, R., Lichtfers, U., Schuda, V., Removal of Carbon Dioxide from Combustion Exhaust Gases, U.S. Patent Application, US 2009/0320682 A1, Dec 31, 2009) is to use the potassium salt of a tertiary amino acid such as dimethylglycine (KDiMGly), promoted with a conventional alkanolamine such as monoethanolamine (MEA). Sufficient kinetic and equilibrium data have been recently published to permit the detailed simulation of a CO₂ capture plant using sodium glycinate (NaGly). Public-domain data have been available for Alkazid DIK since at least 1979. NaGly and KDiMGly have recently been implemented within ProTreat®, allowing us to simulate the performance of these solvents.   Learn more here about how amino acid solvents perform relative to others in carbon capture..