Development of high performance anion exchange membranes for diffusion dialysis process

In this article, the development of a series of low-cost anion exchange membranes (AEMs) for the diffusion dialysis process was carried out via the solution casting method. The synthesis of AEMs was confirmed by using Fourier transform infrared spectroscopy. The prepared membranes exhibited a dense structure. They showed an ion exchange capacity of 1.41–1.90 mmol/g, water uptake (W_R ) of 15%–36%, and linear swelling ratio of 3.60%–21% at ambient temperature. They represented excellent thermal, mechanical, and chemical stability. The acid recovery performance of the prepared membranes was evaluated via diffusion dialysis process by employing a simulated mixture of HCl and FeCl₂ as model feed. At 25°C, the acid diffusion dialysis coefficient (U_H+ ) was found in the range of 4.5–28 (10^–3 m/h). Moreover, the separation factor (S) was in the range of 178–305. It showed higher diffusion dialysis performance of the prepared AEMs compared to commercial + membranes DF-120 (U_H = 0.004 m/h, S = 24.3) under the same experimental conditions. The influence of temperature on diffusion dialysis performance of the prepared AEMs was also revealed. Therefore, the synthesized AEMs could be employed as a good candidate for acid recovery.