Determining Adsorption Parameters of Potentially Contaminant-Releasing Materials Using Batch Tests with Differing Liquid-Solid Ratios

Abstract

Adsorption parameters such as the distribution coefficient are required to predict the release behavior of contaminants using advection-dispersion models. However, for potentially contaminant-releasing materials (PCMs) such as dredged sludge and coal ash, these parameters cannot be obtained by conventional adsorption tests. This study developed a method to determine adsorption parameters for PCMs from a set of batch tests conducted in parallel as a function of the liquid-solid ratio (LS-parallel test). This LS-parallel test was performed on sandy soil derived from marine sediment using liquid-solid ratios from 1 to 300 L/kg. The water-contact time was also changed from 10 min to 28 d to elucidate the kinetics or equilibrium of contaminants released from the sample. Adsorption parameters were successfully obtained if the substance was under adsorption control. A column percolation test was performed to confirm the effectiveness of the obtained parameters. Good agreements were observed for SO42− and B, but discrepancies remained for other substances such as F− and as suggesting that improvements are necessary in both the LS-parallel test procedure and the advection-dispersion model.

Nitrate and Dissolved Organic Carbon Release in Sandy Soils at Different Liquid/Solid Ratios Amended with Graphene and Classical Soil Improvers

“…Batch leaching experiments were carried out doing parallel batch tests with different L/S ratios, as proposed by Sakankura et al [20], to better understand the desorption dynamics of the soil-water system. Batch tests were performed using the SSE method described by Schuwirth and Hofmann [16], with the use of deionized water as a rainwater proxy (EC 15 ± 2 µS/cm, pH 6.84 ± 0.01, ORP 154 ± 11 mV).…”

“…In most literature studies the L/S ratio values vary between 2 and 10 [17][18][19]. Parallel batch tests can be used to determine a potential contaminant release in a soil-water system [20]. The release of chemical species, indeed, can be closely linked to the L/S ratio that can influence the solubility of a chemical species and its ability to pass in the liquid phase [21].…”

“…Most of the literature studies such experiments have been conducted using only one L/S. Instead, performing batch experiments with different L/S ratios fosters a better understanding of the interaction among solid and liquid phases [20].…”

Measurement of the Environmental Impact of Materials

“…Leaching tests represent a common thread in the submissions to this Special Issue [ 3 , 4 , 5 , 6 , 13 , 14 , 15 , 16 ]. The underlying mass transfer principles of column leaching tests are discussed by Liu et al [ 14 ], and Sakanakura et al [ 15 ] showed that adsorption parameters can be determined in batch leaching tests with varying liquid–solid ratios. Ash from sewage sludge incineration (SSA) could partly replace phosphate from natural resources such as fertilizer components.…”