Study On The Impregnation Preparation And Application Of The Anion Diffusion Dialysis Membranes

On the basis of domestic existing ion exchange membrane as well as traditional heterogeneous ion exchange membrane manufacturing process,a novel method has been proposed successfully to prepare diffusion dialysis membrane.The properties of the anion exchange diffusion dialysis membrane(including ion exchange capacity,water content,surface resistance,selection transmittance,diffusion performance)have been precisely measured.The effects of impregnation rate,cross-link degree and the thickness on its properties were deeply investigated.And the actual performance in diffusion dialysis process has been accurately evaluated as well.The results of the effect of the operation parameters are followed:the ion exchange capacity and water content are increasing with the increasement of impregnation rate,while the diffusion ability is not;the ion exchange capacity,water content as well as the diffusion ability are decreasing as the cross-link degree rising;increasing the thickness of wet membrane has negligible influence on these properties,except remarkably weakening the diffusion ability.The actual performance of these membranes prepared by different parameters and commercial diffusion dialysis membrane are evaluated in diffusion dialysis process.The result shows that these membrane can be used in DD process,but the recycling rate of acid is a few lower than that of commercial membranes produced in Japan.In order to improve the diffusion ability,additive agent is used to modify diffusion dialysis membrane.After optimization,5 wt%PEG-800 was added in the membrane.It has been proved that this membrane could recycle 90%HCl and intercept 85%NaCl in DD process with the 0.9 L/(m3·h)flow velocity,which is comparable to the ASTOM membrane.The membrane prepared by impregnation method flexible in impregnation rate,cross-link degree and the thickness to satisfy industry application according to practical condition.It is foreseeable that the membrane with high properties and adaptability will have great potential and competitive advantage in complex industry diffusion dialysis application.