Characteristics of competitive adsorption between 2-methylisoborneol and natural organic matter on superfine and conventionally sized powdered activated carbons

Abstract

18When treating water with activated carbon, natural organic matter (NOM) is not only a target for 19 adsorptive removal but also an inhibitory substance that reduces the removal efficiency of trace 20 compounds, such as 2-methylisoborneol (MIB), through adsorption competition. Recently, superfine 21 (submicron-sized) activated carbon (SPAC) was developed by wet-milling commercially available 22 powdered activated carbon (PAC) to a smaller particle size. It was reported that SPAC has a larger 23 NOM adsorption capacity than PAC because NOM mainly adsorbs close to the external adsorbent 24 particle surface (shell adsorption mechanism). Thus, SPAC with its larger specific external surface 25 area can adsorb more NOM than PAC. The effect of higher NOM uptake on the adsorptive removal of 26 MIB has, however, not been investigated. Results of this study show that adsorption competition 27 between NOM and MIB did not increase when NOM uptake increased due to carbon size reduction;

Geosmin and 2-methylisoborneol removal using superfine powdered activated carbon: Shell adsorption and branched-pore kinetic model analysis and optimal particle size

“…The same influence of NOM on the adsorption capacity between SPAC and PAC suggests the same loading of NOM that compete with MIB for adsorption sites. Details for the effect of NOM loading on SPAC and PAC adsorption are seen elsewhere (Matsui et al, 2012). The presence of NOM also reduced the geosmin adsorption capacities of SPAC and PAC to a similar extent ( Figure 1E); as with MIB, the geosmin adsorption capacity of SPAC10 in the presence of NOM was also higher than that of PAC10.…”

“…The sample was transported in polyethylene tanks and stored at 4 °C. The water was filtered through a 0.2-µm-pore membrane (DISMIC-25HP; Toyo Roshi Kaisha, Tokyo) and diluted to adjust the dissolved organic carbon concentration to ~1.5 mg/L; the diluent used for this purpose was prepared by amending ultrapure water (Milli-Q Advantage, Millipore Co.) with salts to obtain an ionic composition similar to that used in a previous study (Matsui et al, 2012). Stock solutions of MIB and geosmin were prepared by dissolving the pure chemicals (Wako Pure Chemical Industries, Osaka, Japan) in ultrapure water.…”

Granular biochar compared with activated carbon for wastewater treatment and resource recovery

“…Once the available adsorption sites are filled the removal efficiency is significantly diminished. Common granular activated carbon (GAC) materials are comprised primarily of micropores (>1 nm) which are highly effective at adsorbing dissolved contaminants, but are easily blocked by suspended solids (Matsui et al, 2012). The development of a bacterial biofilm can aid in the bioregeneration of adsorption sites but this is also limited and eventually the carbon material will need to be replaced (Simpson, 2008).…”

Removal of geosmin and 2-methylisoborneol by bioflocs produced with aquaculture waste

“…Hence, the biological degradation of geosmin and MIB is anticipated with the application of bioflocs. In addition, the biodegradation of geosmin and MIB has been demonstrated in active carbon filters (Elhadi et al 2004;Matsui et al 2012) and sand filers (Ho et al 2007;McDowall et al 2009). However, in the present study, biodegradation was found to be less important than chemical/physical sorption in the overall removal of geosmin and MIB under in vitro conditions.…”