Boron Removal by Electrocoagulation Using Full Factorial Design

Abstract

Saline waters treatment has become increasingly important for drinking water supply in a greater part of the world. However, some serious limitations had recently been discovered during water treatment, among them the boron problem seems to have a critical meaning. According to the WHO regulations (2011), the boron concentration should be reduced to less than 2.4 mg/L for drinking water. The purpose of this study is to investigate the feasibility of electrocoagulation (EC) as a pretreatment process to remove boron from saline waters. To optimize the experimental conditions of boron removal, the effects of some parameters were studied such as inter-electrode distance (d ie ), electrode connection mode, (S/V) ratio, pH i and initial conductivity of the solution (σ i ). Subsequently, an experimental design methodology was implemented to evaluate statistically the most significant operating parameters. The effects of current density, EC time and initial boron concentration and their mutual interaction were investigated using 2 3 full factorial design. At optimal conditions, boron removal from synthetic aqueous solutions containing initial boron concentrations of 5 and 50 mg/L reached 81% and 79%, respectively. Applied to boron removal from seawater samples, EC reduces boron concentration to less to 2.4 mg/L with excessive energy consumption under optimal parameters.

Boron Removal from Mining and Synthetic Effluents by Electrocoagulation Using Aluminum Electrodes

“…Such evidence can be observed in Figure 3, in which the increase in NaNO 3 concentration increased boron removal. These results agree with the literature data [16, 17].…”

“…This is deposited on the surface of the electrode in a process called passivation, in which there is an increase in the resistance of the system and decrease in the efficiency of the method. Thus, despite increasing current density, a significant percentage difference in boron removal was not observed [16]. An alternative to reduce the passivation of electrodes is the addition of soluble anions with aluminum, such as chlorides and nitrates, because such species aid in the solubilization of the formed oxide.…”

Application of Response Surface Methodology to Electrocoagulation Treatment of Hospital Wastewater

“…Thus, electrical energy consumption costs (EECC) of the electrodes at experimental conditions with high removal efficiencies are calculated according to Eq. (23) [41].…”

Treatment of Saline Water Using Electrocoagulation with Combined Electrical Connection of Electrodes

“…Previous studies have shown that the EC method is an effective tool for treating various water contaminants in textile wastewater [12,20,21,28], chemical fiber wastewater [29], algae or microorganisms [30], oily wastewater [31][32][33], restaurant wastewater [34,35], sewage water [35], arsenic [36][37][38], fluoride [39][40][41][42], boron [43,44], and nitrite [45,46]. The EC process has also been utilized in the removal of different metal ions from water, e.g.…”