Laboratory and pilot-scale investigation of soil cations behavior in conjunction with electrokinetic remediation of inorganic pollutants

Soil electrokinetics (SEK) has a variety of applications, one of which is remediating contaminated soils that contain inorganic contaminants. The SEK remediation (SEKR), which is regarded as a physicochemical separation technique, is unable to distinguish between various ions in removal. In continuation with our recent publication in IJEST titled " Scaling up soil electrokinetic removal of inorganic contaminants based on lab chemical and biological optimizations " [1], which focused on the enhancement of SEKR of inorganic pollutants in real soils, these results are expanded upon in this article to show how cations linked to inorganic contaminants are removed. In the present investigation, the behavior/migration of six cations — Mg, Ca, Ba, Na, Li, and K — was illustrated. The findings demonstrated that the amount of Mg removed using the perforated cathode pipe SEKR system (PCPSS) under the influence of an electric field was proportionate to the rise in soil acidity. It was found that the best chemical to combine with soil to improve the removal of calcium was formic acid (pH 1). Compared to Mg, the amount of Ca removed was greater. The application of formic acid (pH 1) decreased the quantity of Ba accumulation spots/areas within the PCPSS apparatus. Using the recommended enhancing reagents, the content ratios with the removed Na had the lowest values, which exhibit the best rates of removal. In addition to decreasing the accumulation percentages around the cathode pipes (bottom layers), applying formic acid (pH 1) enhanced the amounts of Li removed from the surface layers as compared to the other treatments. After the pilot scale unit of the PCPSS was terminated, the removal percentages of the investigated cations were greatest for Na (lowest content ratios). Since Na is thought to be the primary obstacle to reclaiming salt-affected soil, it is highly recommended to recover salt-affected soil and remove inorganic pollutants simultaneously using the PCPSS pilot scale unit.