Electrochemical Coagulation of Clay Suspensions

Abstract

Abstraet--!n the electrocoagulation process a suspension of kaolinite and bentonite is coagulated by electrochemical treatment where aluminum anodes are dissolved and aluminum ions react with clay particles, forming flocs which precipitate. Several factors affecting the efficiency of electrocoagulation are investigated. They include NaC1 concentration, voltage, and flow conditions within the cell. Increased NaC1 concentration led to lower electric resistance and cleaner running electrodes. Enhanced shear associated with recirculation resulted in clear supernatant and more compact flocs. While increasing the feed rate, which was equivalent to decreasing aluminum concentration through the system, reduced cake height but increased turbidity.

Fundamentals, present and future perspectives of electrocoagulation

“…In addition to these the following advantages can be added: electrochemical based systems allow controlled and rapid reactions, smaller systems become viable and, instead of using chemicals and micro-organisms, the systems employ only electrons to facilitate water treatment. Of the known electrochemical techniques, there is much interest in using electrocoagulation for treatment of wastewater containing, heavy metals [5][6][7], foodstuff [8,9], oil wastes [10,11], textile dyes [12][13][14][15][16][17], fluorine [18], polymeric wastes [19], organic matter from landfill leachate [20], suspended particles [21][22][23][24], chemical and mechanical polishing wastes [25], aqueous suspensions of ultrafine particles [26], nitrate [27], phenolic waste [28], arsenic [29], and refractory organic pollutants including lignin and EDTA [30]. Another approach of EC is for drinking water treatment [31,32].…”

A parametric comparative study of electrocoagulation and coagulation using ultrafine quartz suspensions

“…Electrocoagulation can be used for many purposes such as treatment of clay suspensions [4], removal of boron from boroncontaining solutions [5,6], treatment of textile wastewater [7], removal of phosphate from aqueous solutions [8], separation of pollutants from restaurant wastewater [9], removal of arsenic from water [10], urban wastewater treatment [11], removal of chromium (Cr(VI)) [12,13] and removal of heavy metals [14].…”

Treatment of orange II azo-dye by electrocoagulation (EC) technique in a continuous flow cell using sacrificial iron electrodes

“…A number of authors have reported the treatments of textile dye wastewater by EC technique [6][7][8][9][10]. In addition specific applications of EC include, defluorination of drinking water [11], industrial wastewater containing heavy metals [12][13][14], oil-containing wastewater [15], foodstuff containing wastewater [16,17], organic matter from landfill leachate [18], wastewater containing suspended particles [19][20][21][22], chemical and mechanical polishing waste [23], separation of aqueous suspensions of ultrafine particles [24], removal of nitrate from wastewater [25], recovery of phenolic compounds [26], arsenic removal [27], refractory organic pollutants including lignin, EDTA [28], and polyaromatic organic pollutants [29].…”