Separation of Taurine and Na2SO4 Using in Situ Formation of Deep Eutectic Solvents: Experiments and Computation Simulation

Abstract

As an important and free amino acid, taurine (Tau) shows extensive application in pharmaceuticals. The coexistence of inorganic salts during the production process affects the purity and quality of Tau. Present study firstly described a novel method to separate Tau and Na2SO4 by forming deep eutectic solvents (DESs) in situ. Ethanolamine (MEA) was chosen as the optimal hydrogen bond donor to pair with Tau. After removal of Na2SO4, taurine was stripped out from in situ DES using n-propanol as reverse solvent with the yield of 98% and trace impurities (Na2SO4 and NaCl contents less than 13.70 mg•g -1 and 12.93 mg•g -1 , respectively). On the optimized parameters, the Tau purification and separation process were further elucidated using quantum chemical calculations and molecular dynamics simulations together. Results showed the interaction energy of 116.1 kJ/mol between MEA and Tau, confirming the superiority of Tau purification using DES in situ.