REMOVAL OF TOC BY ACTIVATED CARBON: CORRELATION WITH Kow

Abstract

Adsorption of aqueous organics depends on the hydrophobic and hydrophilic nature of the organics as well as on the nature of the sorbent. The hydrophobic and hydrophilic nature is ascertained by the octanol water coefficient (Kow) of the organic compound. Kow of the aqueous samples containing single organic is documented in the literature. In other words Kow of individual organic compound is reported. 1-lowever, the natural water samples contain more than one organic compound. The aqueous samples could be the mixture of several hydrophilic organics, hydrophobic organics or a combination of the two. The Kow of such samples is likely to depend on the concentration and nature of the organics present in the water sample. The objectives of the present investigation are to (i) measure Kow of the synthetic water samples of known composition, (ii) study the removal of organics by the activated carbon (AC) in batch reactors and (iii) explore the correlation, if any, between Kow and sorption parameters. To achieve these, six synthetic aqueous samples containing Four organic compounds were prepared, The Kow of these samples was measured at different ratio of octanol to water. The Kow varied from I to 170. The Kow of the individual organic compound that was added to the synthetic samples was also measured and compared with the values reported in the literature. Each of these samples was stirred with AC to obtain sorption isotherms and sorption parameters such as sorption capacity and partition coefficient. Results indicate a correlation between Kow and sorption parameters. 'IThus Kow can be used to predict the sorption behavior of the aqueous samples that contain more than one organic compound.