Adsorption of synthetic organic shock loadings

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Date of Original Version



A pilot plant designed to simulate conventional water treatment processes augmented by powdered activated carbon (PAC) and granular activated carbon (GAC) adsorption is operated to investigate the removal of combined shock loadings of isomers of trichloro and tetrachlorobenzene, C-46, and C-56 present in the same influent matrix. Applications of each of the organic compounds are made as an increasing step function, with a cycle consisting of one series of four concentration steps (2,10,100, and 200 μg/L). In order to study desorption reactions, each step loading lasts 32 hours separated by a 24-hour period during which no applications of the organic compounds are made. A total of three cycles are evaluated; the resulting data demonstrates that PAC dosages as high as 50 mg/L are not as effective as a GAC adsorption bed with an empty bed contact time of 10 minutes. The Freundlich isotherm is found to closely describe the equilibrium condition with correlation coefficients ranging from 0.948 to 0.986 for each of the compounds. Desorption of the organics from the upper layers of the GAC bed is observed as early as the first cycle of operation. © ASCE.

Publication Title, e.g., Journal

Journal of Environmental Engineering (United States)