Desorption experiments and modeling of micropollutants on activated carbon in water phase: application to transient concentrations mitigation

Abstract

International audienceExperimental studies and numerical modeling were conducted to assess the feasibility of a granular activated carbon column to buffer load variations of contaminants before wastewater treatment devices. Studies of cycles of adsorption, and more especially desorption, of methyldiethanolamine (MDEA) and 2,4-dimethylphenol (2,4-DMP) have been carried out on granular activated carbon (GAC). Dynamic variations of contaminants concentrations were run at several conditions of duration (peaks). GAC fixed-bed exhibited a stable adsorption/desorption capacity after undergoing two conditioning cycles. The study of pollution peaks revealed that attenuation is largely dependent on the targeted pollutant: 2.4 ± 0.5 % attenuation/cm of bed for MDEA and 6.0 ± 1.2 % attenuation/cm of bed for 2,4-DMP. Mass balances calculated from both injected and recovered pollutant during peaks were respected. Finally, a coupling of the linear driving force model and isotherms models was used to fit experimental data for both adsorption breakthrough curves and desorption curves. The model was used to predict adsorption and desorption behaviors of following cycles. Good agreement with experimental values was obtained

Influence of intermittent flow on removal of organics in a biological activated carbon filter (BAC) used as post-treatment for greywater

“…This removal indicates that TOC is biologically degraded ( Sakoda et al., 1996 ). Bourneuf et al. (2016) evaluated the response of peak loading and observed only attenuation of peaks but no long-term removal indicating the GAC acting as a temporary sink.…”

Low-cost activated carbon for adsorption and heterogeneous ozonation of phenolic wastewater

“…The adsorption of t-BuOH onto AC is supposed to be negligible and does not compete with 2,4-DMP: it cannot be easily adsorbed by AC because of its high polarity and its very low adsorption rate in comparison with the decomposition rate [23]. Nevertheless, introduced Table 3 Adsorption capacities for various 2,4-DMP/adsorbent systems [10,46,47] Adsorbent (reference) S BET (m 2 g -1 )…”

Contents Vol. 163

“…The adsorption of t-BuOH onto AC is supposed to be negligible and does not compete with 2,4-DMP: it cannot be easily adsorbed by AC because of its high polarity and its very low adsorption rate in comparison with the decomposition rate [23]. Nevertheless, introduced Table 3 Adsorption capacities for various 2,4-DMP/adsorbent systems [10,46,47] Adsorbent (reference)…”

“…Ceca [46] in large excess, there is enough t-BuOH near the AC surface to react with the radicals formed in the heterogeneous phase. Fig.…”