AWWA WQTC71427

Adsorption of two synthetic organic compounds (SOCs) by three single-walledcarbon nanotubes (SWNTs) was systematically studied under different water qualityconditions. For comparison, a microporous activated carbon fiber (ACF10) and a bimodal porousgranular activated carbon (HD4000) with similar surface chemistry were also employed in thiswork. Experimental results demonstrate that the competition between SOCs and NOM uptakesof adsorbents with similar surface affinity to water was not controlled by surface area or porevolume but controlled by their pore size distributions. Both direct competition for adsorptionsites and pore blockage by NOM occurred in the adsorption of SOCs. For the microporousACF10, due to the inaccessibility of the small micropores to NOM macromolecules, poreblockage predominated in the competition, whereas for the bimodal mesoporous HD4000, directsite competition dominated, which led to a reduction in SOC uptake and in surface heterogeneityof the adsorbent. Compared with ACF10 and HD4000, the effects of NOM preloading andsimultaneous adsorption on SWNTs were much weaker, implying that once released into naturalwater body, SWNTs will adsorb a considerable amount of toxic SOCs and transfer them to othersystems by the transportation of the nanotubes. Compared with the effect of NOM, the effects ofionic strength and pH of the bulk solution on the adsorption of SOCs on SWNTs wereinsignificant. Includes 19 references, tables, figure.

Product Details

Edition:

Vol. - No.

Published:

11/01/2009

Number of Pages:

8

File Size:

1 file , 860 KB