| Abstract: | A hollow fiber supported liquid membrane (SLM) process was investigated experimentally and theoretically for the separation of NH3 from aqueous solutions containing NH3 and CO2. DTPA and D2EHPA were used as carriers and n-decanol was used as a diluent in this process. The membrane stripping experiments, as well as the extractive equilibrium experiments, indicate that DTPA is a better carrier than D2EHPA in relation to the increase in the NH3 stripping rate. The influence of operating conditions, such as flow rate, the ratio of NH3 to CO2, and carrier concentration, on the membrane stripping rate were examined. The experimental data demonstrate that the NH3 stripping rate by an SLM process is not significantly influenced by the amount of CO2 present, as is that by the supported gas membrane. To predict the stripping of NH3 from solutions containing NH3 and CO2, a mathematical model incorporating chemical equilibria and Nernst–Planck diffusion was developed to describe the mass transport. The experimental data suggested that the SLM process can effectively strip NH3 from aqueous solutions containing NH3 and CO2. |
