扩散渗析法回收铝箔腐蚀废液中硝酸

Recovery of nitric acid in aluminum foil etching wastewater by diffusion dialysis

采用扩散渗析法回收铝箔腐蚀废液中的硝酸,主要考察流量、废液中硝酸铝浓度和硝酸浓度等因素对回收酸浓度、酸回收率以及铝离子截留率的影响.结果表明:回收酸浓度和酸回收率随着流量的增大而减小,随着废液中硝酸铝浓度的增大而增大;废液中硝酸浓度对回收酸浓度、酸回收率以及铝离子截留率的影响不大.综合本文的实验结果,酸回收率最高为84.90%,此时,流量为0.24L/h(流量比为1∶1)、废液中硝酸浓度为1.30mol/L、硝酸铝浓度为0.49mol/L.

A lot of etching wastewater were generated in the production process of aluminum foil. A diffusion dialysis was adopted to recover nitric acid from aluminum foil etching wastewater. The effects of flow rate, aluminum nitrate andnitric acid concentration in feed on recovered acid concentration, acid recovery ratio and aluminum rejection ratio were investigated. The results showed that the recovered acid concentration and acid recovery ratio decreased with the increase of flow rate, and increased with the aluminum nitrate concentration in feed increased, and while there is no obvious influence of nitric acid concentration in feed on them. Based on the results, it could be concluded that the highest acid recovery ratio in this study was 84. 90%, and the operation condition is that the flow rate was 0. 24 L/h （flow rate ratio was 1.0）, the aluminum nitrate and nitric acid concentration in feed were 0.49 mol/L and 1.30 mol/ L, respectively.