Heavy metal removal from simulated wastewater using electrochemical technology: optimization of copper electrodeposition in a membraneless fluidized bed electrode

Abstract

Heavy metal removal from industrial wastewaters has been intensively studied, since it is well known that they can cause severe problems to human health and aquatic life, even at very low concentrations. In this work, it was demonstrated that electrodeposition in fluidized bed electrode (FBE) can be efficiently employed to remove metal ions from solution, avoid contamination, and recover the metal. Copper electrodeposition from diluted solutions was efficiently performed using a membraneless FBE. The average current efficiency (ACE), average energy consumption (AEC), and space-time yield (AY) was optimized taking into account the operational and process variables. It was noted that for all response variables studied, the raise of supporting electrolyte concentration (C s ) contributed to improvements in the process. The operational conditions current (I) and bed expansion (E) determined the values of CE, Y, and EC under activated control, but the initial copper concentration (C 0 ) determined how long the electrodeposition process will work under activated or mass transfer control, thus affecting the average values of CE, Y, and EC. Considering C 0 of 500 mg L -1 , copper can be optimally recovered with ACE [60 %, AY[38 kg h -1 m -3 , and AEC\4.0 kWh kg -1 by applying the lowest I and the highest levels of E and C s . It was concluded that the electrochemical technology using a membraneless FBE reactor is economically competitive and be applied for the treatment of wastewaters contaminated with copper or other metals.

Applications of Combined Electrocoagulation and Electrooxidation Treatment to Industrial Wastewaters

“…Consequently, the energy consumption per unit volume of treated wastewater is reduced as shown in Eq. (14).…”

“…With the strict environmental regulations on wastewater discharge, there is a need to develop efficient technologies and approaches at large scale for the treatment and management of industrial wastewater so that clean water quality can be maintained and amount increased while environmental protection and sustainability are achieved [1-5, 8, 11-13]. There has been an increasing interest in the use of electrochemical wastewater treatment technologies, such as electrodeposition [14], electrodisinfection [15], electro-Fenton [16], electrosorption [17], EOx [4] and EC [1] and their sequential [8,18], and simultaneous [19,20] combinations for the treatment of industrial wastewaters in recent years.…”

Alternating Current for the Selective Electrodeposition of Cadmium, Iron, and Chromium Method Development for Simulated Industrial Wastewater Sludge

“…This process allows metal ions to deposit on the electrode surface in their neutral state. Electrochemical methods have been employed in several applications, such as battery recycling [9], water desalination [10], and treatment of various industrial wastewaters [11][12][13]. While this method has proven to be efficient in reducing the concentration of metal ions in solution, it can be difficult to separate individual metals deposited due to coelectrodeposition or inhibition.…”

Preparation and Modification of Mullite Whiskers/Cordierite Porous Ceramics for Cu2+ Adsorption and Removing

“…In recent years, various methods for heavy metal removal from wastewater have been extensively proposed, including but not limited to chemical precipitation, ion exchange, adsorption, membrane filtration, and electrochemical technologies. − Among these techniques, the adsorption method has been extensively researched because of its high removal efficiency and adsorption capacity, and simple and convenient processes . It has become a popular method for heavy metal removal from wastewater .…”