三维电极法去除配位电镀废水中的镍离子和铜离子

将颗粒状活性炭作为三维电极的粒子,采用三维电极法去除配位电镀废水中的镍离子和铜离子。考察了pH值、电流、极板间距、炭水比(粒子电极活性炭与处理水量的体积比)对镍离子和铜离子去除率的影响。在设定的范围内,镍离子和铜离子的去除率随pH值的升高呈现先升后降的变化趋势,随电流和炭水比的增大而升高,随极板间距的增大而降低。当废水中镍离子和铜离子的初始质量浓度分别为82.309 3mg/L和52.761 5mg/L、活性炭的体积为1 000mL、处理时间为2.0h时,最佳的处理工艺条件为:pH值4、电流0.6A,极板间距20cm,炭水比10∶9。此时,镍离子和铜离子的去除率分别为83.40%和86.20%。出水经过混凝沉淀后,镍离子和铜离子的去除率分别达到99.87%和99.68%,在出水中的质量浓度分别为0.107 2mg/L和0.169 3mg/L,出水水质达到《电镀污染物排放标准》(GB 21900—2008)中表2的排放限值。

Removal of Nickel Ions and Copper Ions from Complexing Electroplating Wastewater Using Three-Dimensional Electrode Method

Activated carbon was used as the particle in three-dimensional electrode,and three-dimensional electrode method was applied to removal nickel ions and copper ions from complexing electroplating wastewater.The influences of pH value,current,electrode plate distance as well as carbon-water ratio (the volume ratio of particle electrode activated carbon to water) on the removal rate of nickel ions and copper ions were investigated.In the specified range,the removal rate of nickel ions and copper ions increased first and then decreased with the rising of pH value,increased with the increasing of current and carbon-water ratio,however,it decreased with the increasing of electrode plate distance.When the initial mass concentration of nickel ions was 82.309 3 mg/L,the initial mass concentration of copper ions was 52.761 5 mg/L,the volume of activated carbon was 1 000 mL and reaction time was 2.0 h,the optimal operating conditions were as follows:pH value 4,current 0.6 A,electrode plate distance 20 cm,carbon-water ratio 10;9.Under these optimal conditions,the removal rate of nickel ions and copper ions was 83.40％ and 86.20％,respectively.After coagulation precipitation,the removal rate of nickel ions and copper ions could reach 99.87％ and 99.68％,respectively,and the mass concentration of nickel ions and copper ions in processed wastewater was 0.107 2 mg/L and 0.169 3 mg/L.The effluent quality meet the emission standard of pollutants for electroplating (GB 21900-2008)table 2 limits.