Abstract
Jordanian diatomaceous clay modified by some cationic surfactantsdodecyltrimethylammoniumbromide (DDTMA-Br), tetradecyltrimethylammonium bromide (TDTMA-Br), Hexadecyltrimethylammonium bromide(HDTMA-Br), hexadecltrimethylammonium chloride HDTMA-Cl and octadecyltrimethylammonium bromide (ODTMA-Br) were prepared. The chemical and structural properties of raw and modified samples were studied using X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), total organic carbon (TOC), and Fourier transform infrared spectroscopy (FTIR). The adsorption capacities were estimated by methylene blue method. The use of surfactants does not change the mineral structure of the diatomaceous clay. Experiments were done to study the role of surfactants modified diatomaceous clay in the removal of phenol, 4-chlorophenol, and 4-nitrophenol from their aqueous solutions at different PH ranges. The removal of phenol was up to 75% at PH equal to 10.5, for 4-chlorophenol 95 % at PH equal to 8.0 and 4-nitrophenol is 98 % at PH equal to 6.5. The adsorption isothermsof modified surfactants diatomaceous clay indicates that phenol and its derivatives follow type 1, which is the Langmuir isotherms. The results have revealed that the modified diatomaceous clay improve the adsorption of phenols from aqueous solutions better than the raw ones.