چكيده به لاتين
In this work, the supported liquid membrane was applied in order to evaluate the effect of nanoparticles presence on gadolinium and neodymium removal from aqueous media. To reach this goal, the experiments were conducted via and supported liquid membrane containing TiO2/SiO2 nanoparticle in kerosene and Aliquat 336 as membrane phase. Via these experiments the effect of nitric acid concentration and the carrier concentration on permeation coefficient were studied and 2 M HNO3 for both neodymium and gadolinium and concentration of 0.02 M Aliquat 336 for neodymium removal and 0.015 M Aliquat 336 for gadolinium removal were reported as the optimum conditions for these two parameters. In addition, to determine the influence of the nanoparticles presence in the system, size, mass fraction and type of nanoparticle were tested. The results showed that applying nanoparticles can generally improve the mass transfer in the supported liquid system, although increment of nanoparticle size and concentration more that a specific value may lead to undesireable outcomes such as pores blockage and paticles agglomeration and consequently reduction of mass transfer in the system. Also, it was observed that using nanoparticles can rise the permeation coefficient up to 42% for 20 nm SiO2 nanoparticles with the mass fraction of 0.04 wt% for neodymium removal and in case of using 70 nm with the mass fraction of 0.12 %wt the permeation was droped by 48% for Gadolinium removal by supported liquid membrane. Besides, probable mechanisms of nanoparticle presence in supported liquid membrane were evaluated and the Brownian diffusion was known as the most dominant mechanism of mass transfer. Additionally, mass transfer coefficient correlations were developed via theoretical equations and heat and mass transfer analogy which resulted in 17.03% and 21.28% of AARE, respectively. Finaly, a 2-D model was provided to better clarify the effect of nanoparticles presence in supported liquid membrane which approved the experimental results.
