Geochemical Modeling of Trivalent Chromium Migration in Saline-Sodic Soil during Lasagna Process: Impact on Soil Physicochemical Properties

Abstract

Trivalent Cr is one of the heavy metals that are difficult to be removed from soil using electrokinetic study because of its geochemical properties. High buffering capacity soil is expected to reduce the mobility of the trivalent Cr and subsequently reduce the remedial efficiency thereby complicating the remediation process. In this study, geochemical modeling and migration of trivalent Cr in saline-sodic soil (high buffering capacity and alkaline) during integrated electrokinetics-adsorption remediation, called the Lasagna process, were investigated. The remedial efficiency of trivalent Cr in addition to the impacts of the Lasagna process on the physicochemical properties of the soil was studied. Box-Behnken design was used to study the interaction effects of voltage gradient, initial contaminant concentration, and polarity reversal rate on the soil pH, electroosmotic volume, soil electrical conductivity, current, and remedial efficiency of trivalent Cr in saline-sodic soil that was artificially spiked with Cr, Cu, Cd, Pb, Hg, phenol, and kerosene. Overall desirability of 0.715 was attained at the following optimal conditions: voltage gradient 0.36 V/cm; polarity reversal rate 17.63 hr; soil pH 10.0. Under these conditions, the expected trivalent Cr remedial efficiency is 64.75 %.

Process Optimization and Modeling of Phenol Adsorption onto Sludge-Based Activated Carbon Intercalated MgAlFe Ternary Layered Double Hydroxide Composite

“…In addition, the high predictive ability of the model is manifested in high values and closeness of the different coefficients of determination R 2 (0.998), R 2 -predicted (0.993), and R 2 -adjusted (0.959) (as provided in Table 2 ). Thus, this implies that the values of both the biased and non-bias R 2 and well the LOF are in conformity with one another, thereby meeting the requirements for RSM predictive models [ 51 ]. Meanwhile, the normal probability plot depicted in Figure 3 b implies that the model satisfied the assumption of normality.…”

Remediation of Heavy Metals Contaminated Soils: A bibliometric Network Analysis

“…Electrokinetic remediation is the use of electric potential gradients to remove heavy metals from the soil through electromigration and electroosmosis [18]. As early as the 1930s, for the high-salinity soil of a certain place in India, some scholars used the method of electric remediation to conduct experiments on the sodium salt in the alkaline soil to study the restoration of the alkaline soil to the level of arable land [19]. Laboratory and field results show that by applying a DC electric field, sodium ions can be extracted from the soil.…”