Commercially available bentonite clay was first converted into Na+saturated form by stirring with 0.1 M NaCl for 4 h. The Na-bentonite obtained is filtered and dried at a temperature of 70◦C in an air oven for overnight. The product is powdered and again converted into organo form by treating with surfactant. For the synthesis, the amount of HDTMA corresponding to 100% of the cation exchange capacity of the Na-bentonitewas dissolved in 1 L of distilled water and added to 20 g Na-bentonite. The suspension was shaken for 6 h at 60◦C, filtered,washed several times with distilled water and then dried at 70◦C for 24 h.