Electrolytic ammonia removal and current efficiency by a vermiculite-packed electrochemical reactor

Abstract

The ammonia removal as well as the current efficiency during electrolysis was investigated by using a vermiculite-packed electrochemical reactor under continuous mode. Experimental results showed that adsorption of ammonia by vermiculite and electrolytic desorption of ammonia simultaneously existed in the reactor, leading to 89% removal of initial 30 mg N/L ammonia and current efficiency of 25% under the condition of 2.0 A, 6.0 min hydraulic retention time with 300 mg Cl/L chloride as the catalyst. The ammonia removal capacity had a linear relationship with the products of hydraulic retention time, current and chloride concentration within experimental conditions. The treatment results of secondary effluent indicated that 29.9 mg N/L ammonia can be reduced to 4.6 mg N/L with 72% removal of total nitrogen and a current efficiency of 23%, which was 2% less than synthetic wastewater due to the reducing components in the real wastewater.

Inactivation of Rhizoctonia solani in fertigation water using regenerative in situ electrochemical hypochlorination

“…5b). The suspected cause for this decreased effluent free chlorine with the presence of fertilizer is due to the consumption by ammonium and transformations to other nitrogenous species due to direct oxidation by the anode and indirect oxidation from free chlorine 63–66 . Chlorine is known to react with various organic and inorganic components in water, such as microorganisms but also including ammonium and ferrous iron 1,37,67 .…”

Pollutant Removal from Synthetic Aqueous Solutions with a Combined Electrochemical Oxidation and Adsorption Method

“…In addition, Ding et al [ 31 ] removed 90% of ammonia using Ti/RuO 2 -Pt electrodes by the EO method. Similarly, Li et al [ 23 ] reported an 89% ammonia removal at an initial concentration of 30 mg/L using a vermiculite-packed electrochemical reactor. Overall, the ammonia elimination efficiency in the current study was similar to those in previous studies.…”

“…We selected the initial concentrations of pollutants based on preliminary experiments and a literature review. For example, Li et al [ 23 ] used 25 mg/L as the initial ammonia concentration during the application of an electrochemical ion-exchange reactor for ammonia removal, while Peings et al [ 24 ] used 30 mg/L as the initial phenol concentration for the removal from an aqueous solution by advance oxidation.…”

Recyclable Recovery of Lead from Zinc Hydrometallurgy Residue: By NH4Cl-MgCl2 Leaching and Novel Cyclone-Electrowinning

“…The use of NH 4 Cl as a leaching agent, for one function, provided chloride ions; another crucial role in the electrolytic process was to inhibit the evolution of chlorine gas on the anode, furthermore to avoid the formation of lead dioxide in the anodic oxidation. The following reactions would occur during electrolysis , normalc athode : 0.25em PbCl 4 2 − + 2 normale = Pb + 4 Cl − normala node : 0.25em 2 Cl − − 2 normale = Cl 2 4 Cl 2 + 2 NH 4 + = N 2 + 8 H + + 8 Cl − …”