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Rapid small‐scale column tests (RSSCTs) have been developed for simulating the removal of organic micro‐pollutants (OMPs) in full‐scale fixed‐bed carbon adsorbers to reduce time, materials, and labor costs. However, when dissolved organic matter (DOM) is present, OMP breakthrough profiles obtained from RSSCTs often do not match those at full‐scale because DOM fouling scales differently than OMP adsorption for different‐sized adsorbent particles. To overcome this limitation, single and multiple linear regression analyses were used to develop relationships between DOM concentration, OMP physical–chemical properties (log D, Abraham solvation parameters), and early (10%) OMP breakthrough at full‐scale with and without RSSCT data. It was found that statistically significant regressions could be developed using the largest database assembled to date consisting of 175 RSSCT and full‐/pilot‐scale data pairs, including activated carbons generated from bituminous coal, lignite, coconut shells, and wood‐based biochar, 58 OMPs with a range of adsorbabilities, and waters containing DOM from diverse origins. [ABSTRACT FROM AUTHOR]

This study examined sorption of the human and veterinary antibiotic sulfamethoxazole (SMX) at environmentally relevant concentrations from laboratory clean water, surface water, stormwater, and wastewater effluent to wood and wastewater-sludge derived biochars produced under a wide range of conditions. SMX sorption by commercial powdered activated carbon (PAC) was also quantified as a benchmark. Wood-based biochar produced around 850 °C performed similarly to PAC. Biochar sorption capacity increased with surface area up to ∼400 m 2 /g. However, a further increase in surface area did not correspond to an increase in sorption capacity. Sorbent H:C ratios correlated with SMX uptake by PAC and wood-based biochars, but not for the sludge-based biochars. This is possibly due to an indirect influence of the high ash content in sludge-based biochars, as the isolated ash fraction exhibited negligible SMX sorption capacity. The presence of dissolved organic matter (DOM) in the natural and anthropogenic waters fouled most of the sorbents (i.e., decreased SMX uptake). The sludge-based biochars experienced less DOM fouling relative to wood-based biochar, particularly in the wastewater effluent. Biochar and PAC sorption kinetics were similar when examined over a contact time of four-hours, suggesting their performance ranking would be consistent at contact times typically utilized in water treatment systems. In the presence of DOM, SMX relative removal (C/C 0 ) was independent of SMX initial concentration when the initial concentration was below 10 μg/L, thus permitting the relative removal results to be applied for different SMX initial concentrations typical of environmental and anthropogenically impacted waters. [ABSTRACT FROM AUTHOR]