Solvent extraction separation of tyramine from simulated alkaloid processing wastewater by Cyanex 923/kerosene

Effluents from alkaloid processing plants could have adverse environmental effects. In this work, liquid-liquid extraction using trialkylphosphine oxide Cyanex 923 (TRPO) as an extractant has been proposed for alkaloid wastewater treatment. Partition behaviors of tyramine and morphine against pH were discussed and extraction equilibrium experiments were performed with various organic solvents at the optimal conditions. 50 v/v% TRPO/kerosene was found as suitable solvent and showed good extraction performance due to hydrogen bond interaction and hydrophobic interaction with alkaloid compounds. Extraction mechanism and the complex species extracted were identified by slope analysis and FTIR spectra. Experimental overall mass transfer coefficients and recovery of tyramine were obtained under a range of hydrodynamic conditions in a handmade hollow fiber contactor. Model predictions based on a resistance in series model matched well with these experimental values for 50% TRPO/kerosene systems. Mass transfer resistances in this process were also analyzed. (C) 2012 Elsevier B.V. All rights reserved.