COMPETITIVE ADSORPTION OF ORGANIC POLLUTANTS FROM WASTEWATER ONTO ORGANOCLAY IN BATCH ADSORBER

摘要

Batch experiments were carried out to obtain the adsorption isotherms of phenol, p-nitrophenol and salicylic acid (single, binary and ternary systems) onto modified clay (organoclay). This clay was prepared from blending of local bentonite with quaternary ammonium. The organoclay was characterized by XRD and total organic carbon. The XRD diagram Also indicting that the basal spacing of 13.6 °A for natural clay increased to 18.2 °A for modified clay. The total organic carbon is found to be (20.3%) for modified clay more larger than natural clay (1.2%). The Freundlich isotherm model fitted well the adsorption data for each solute in a single system, whereas the combination of Langmuir-freundlich model was used in binary and ternary systems. A batch adsorber model was used to determine the pore and surface diffusion coefficients for each solute. The results show that salicylic acid is being adsorbed faster than phenol and p-nitrophenol, and the adsorption process was controlled by surface diffusion.