Removal of Cyanide by Electrocoagulation Process

Free cyanide and its related compounds are the most known contaminants whichare released from industrial effluents to the environment; the objective of this study was toevaluate the efficiency electrocoagulation reactor with iron plate in order to find optimumoperational conditions for cyanide removal from cyanide-containing effluents. the reactorwas tested under different operational conditions of voltage (20, 30, and 40 v), detentiontime (20, 30, 40, 60, and 90 min), and influent concentration (20, 30 40, and 50 mg/l). sinceferrous ion capability to react with free cyanide and its related compounds are (97%) wellestablished, iron plate was used as electrode in the present study. additionally, to preventcreating ferric ion and ferric hydroxide precipitates in the reactor which decrease the removalefficiency, bisulfite was applied to hold ferrous ion in the reactor. the optimum operationalconditions were obtained after running the reactor for several times. based on the results, theoptimum removal efficiency was obtained at voltage of 40 v, detention time of 90 min, andinfluent concentration of 50 mg/l. therefore, this process may be considered as an alternativemethod for the removal of cyanide from cyanide- containing wastewaters.