Adsorption of Geosmin and MIB on Activated Carbon Fibers–Single and Binary Solute System

Abstract

The adsorption of two taste-and odorcausing compounds, namely MIB (2-methyl isoborneol-C 11 H 20 O) and geosmin (C 12 H 22 O) on activated carbon was investigated in this study. The impact of adsorbent pore size distribution on adsorption of MIB and geosmin was evaluated through single solute and multicomponent adsorption of these compounds on three types of activated carbon fibers (ACFs) and one granular activated carbon (GAC). The ACFs (ACC-15, ACC-20, and ACC-25) with different degrees of activation had narrow pore size distributions and specific critical pore diameters whereas the GAC (F-400) had a wider pore size distribution and lesser microporosity. The effect of the presence of natural organic matter (NOM) on MIB and geosmin adsorption was also studied for both the single solute and binary systems. The Myers equation was used to evaluate the single solute isotherms as it converges to Henry's law at low coverage and also serves as an input for predicting multicomponent adsorption. The single solute adsorption isotherms fit the Myers equation well and pore size distribution significantly influenced adsorption on the ACFs and GAC. The ideal adsorbed solute theory (IAST), which is a wellestablished thermodynamic model for multicomponent adsorption, was used to predict the binary adsorption of MIB and geosmin. The IAST predicted well the binary adsorption on the ACFs and GAC. Binary adsorption isotherms were also conducted in the presence of oxygen (oxic) and absence of oxygen (anoxic). There were no significant differences in the binary isotherm between the oxic and anoxic conditions, indicating that adsorption was purely through physical adsorption and no oligomerization was taking place. Binary adsorptions for the four adsorbents were also conducted in the presence of humic acid to determine the effect of NOM and to compare with IAST predictions. The presence of NOM interestingly resulted in deviation from IAST behavior in case of two adsorbents, ACC-15 and F-400.

Inversion of loading‐implicit adsorption isotherms by means of the Lambert W function

“…This isotherm is a three‐parameter expression capable of representing type I isotherms 23 . It is sometimes referred to as the Myers isotherm 6,7,38‐45 . It should also be noted that the Redlich–Peterson isotherm was mistakenly referred to as the Jossens isotherm in some papers published in the 1980s 46,47 .…”

“…23 It is sometimes referred to as the Myers isotherm. 6,7,[38][39][40][41][42][43][44][45] It should also be noted that the Redlich-Peterson isotherm was mistakenly referred to as the Jossens isotherm in some papers published in the 1980s. 46,47 This misattribution can still be found in some recent studies.…”

“…46,47 This misattribution can still be found in some recent studies. [48][49][50][51][52] The Jossens isotherm, defined by Eqn ( 5), has been used by several researchers to correlate liquid phase [5][6][7][8][38][39][40][41][42][43][44][45][53][54][55][56][57][58] and gas phase [59][60][61] adsorption data since the 1980s. Least-squares fitting methods were used to estimate the three parameters of the Jossens isotherm.…”

Development and Environmental Applications of Activated Carbon Cloths

“…The influence of the adsorbent pore size distribution on the adsorption of two taste-and odor-causing compounds, namely, 2-methyl isoborneol-C 11 H 20 O (MIB) and geosmin (C 12 H 22 O), from single solute and binary solutions using three different activated carbon cloths and a granularactivated carbon was investigated [158] ( Table 2). The ACC obtained with different degrees of activation had narrow pore size distributions and specific critical pore diameters.…”