Measurement of copper deposition by electrocoagulation/flotation from waste printing developer

The electrocoagulation/flotation treatment (ECF) was employed for the reduction of copper from the waste printing developer in a batch study by using four different aluminum and iron electrode combinations with independent ECF parameters such as current density, interelectrode distance and operating time. The individual and interactive effects of the three main independent ECF parameters were studied by using the response surface methodology. Based on the results, parameters for high copper removal efficiency (95.5%) from the waste printing developer by the ECF were: Al(-)/Al(+) electrode combination with an interelectrode distance of 1.0 cm, operating time of 10 min and a current density of 4 mA cm(2). Moreover, the kinetic study of the ECF treatment of waste printing developer demonstrated that the removal of copper follows the pseudo second-order model with current dependent parameters. For immobilization process of copper in waste ECF sludge, the solidification/stabilization (S/S) treatment was conducted with Portland cement, lime, bentonite, and local clay as immobilization agents. The efficiency of the S/S treatment was monitored by applying leaching tests with one extraction fluid during a certain time. Therefore, using ECF and S/S treatments, copper from the printing effluent can be safely disposed into the environment. (C) 2018 Elsevier Ltd. All rights reserved.