Sorption of ionizable and ionic organic compounds to biochar, activated carbon and other carbonaceous materials

Differential roles of ash in sorption of triclosan to wood‐derived biochars produced at different temperatures

“…; Keiluweit et al., ; Weber & Quicker, ). Moreover, biochars of 300°C had the highest content of ‐OH and ‐COOH (Figure 1a, 1b, and 1d) that can form a hydrogen bond with triclosan (Kah, Sigmund, Feng, & Hofmann, ). Biochars of 900°C (PBC900 and DBC900) had the highest degree of graphitization (lowest I D /I G value) and the greatest SSA and developed micropore structure in carbonaceous fractions (Table , Supplemental and ), which enhanced the sorption of triclosan to carbonaceous fractions by π‐π interaction and pore filling effect (Ahmad et al., ).…”

“…Supplemental displayed that the sorption isotherms of DBCs of 600–900°C were always higher than those of their corresponding PBCs, which was mainly because ash occupied the sorption sites on biochars and decreased the sorption of triclosan to PBCs (Li et al., ; Sun et al., ; Zhang et al., ). Meanwhile, the sorption isotherm for DBCs of 300°C was also higher than that for PBC300, which was possibly because the dominant sorption mechanisms for biochars of 300°C were partition effect and hydrogen bond (Kah et al., ). Ash particles could occupy the sorption sites for forming hydrogen bond.…”

“…The negative charged deprotonated carboxyl group (COO − ) on biochars could combine to the phenolic hydroxyl of triclosan through charge assistant hydrogen bond. The formation of a charge assistant hydrogen bond (biochar‐COO −… H‐O‐triclosan) enhanced the sorption of triclosan to biochar as the pH increased from 3.0 to 5.0 (Ahmad et al., ; Kah et al., ). However, as the pH continued to rise to >5.0, the sorption amount of triclosan to all the four biochars decreased with increasing solution pH.…”

“…The results indicated that biochars of 300 and 900 • C were more beneficial for sorption of triclosan than biochars of 400-800 • C. The biochars of 300 • C (PBC300 and DBC300) had the greatest ratio of H/C (Figure 1c), which suggested their carbonaceous fraction were rich in aliphatic structure (uncarbonized organic matter) (Supplemental Figure S11) that generate strong partition effect (Chen et al, 2008;Han et al 2016;Keiluweit et al, 2010;Weber & Quicker, 2018). Moreover, biochars of 300 • C had the highest content of -OH and -COOH (Figure 1a, 1b, and 1d) that can form a hydrogen bond with triclosan (Kah, Sigmund, Feng, & Hofmann, 2017). Biochars of 900 • C (PBC900 and DBC900) had the highest degree of graphitization (lowest I D /I G value) and the greatest SSA and developed micropore structure in carbonaceous fractions (Table 1, Supplemental Figures S5 and S6), which enhanced the sorption of triclosan to carbonaceous fractions by π-π interaction and pore filling effect (Ahmad et al, 2014).…”

Trends in sensitive detection and rapid removal of sulfonamides: A review

“…Carbon materials used to remove sulfonamides via adsorption include biochar, activated carbon, graphene/GO, CNTs, and their derivatives. These carbon materials can be applied to remove sulfonamides owing to their porous structure, high surface area, and tunable surface functionality [147]. Consisting of inorganic metal ions or metal clusters and plausible adsorption mechanism for sulfachloropyradazine on UiO-66.…”