Phenol and chlorophenol removal from aqueous solution by organobentonites

Experimental investigations were conducted on the adsorption characteristic s of phenol and m-chlorophenol by organobentonites. The organobentonites we re prepared by modifying the natural bentonite by various quaternary amines including tetramethylammonium bromide (TMAB), hexadecyltrimethylammonium b romide (HDTMAB) benzyltriethylammonium bromide (BTEAB), tetraethylammonium bromide (TMAB) and cetylpyridinium bromide (CPB), all surfactants. The empi rical Freundlich isotherm was found to describe well the equilibrium adsorp tion data. Multistage adsorption of phenol or chlorophenol by organobentoni tes was investigated both theoretically and experimentally. Theoretical equ ations were found to predict reasonably well the observed data. Preliminary regeneration of the exhausted organobentonites was also attempted. Results from several test runs showed the potential of regeneration by a simple th ermal method.