Surfactant-modified microporous zeolites for wastewater treatment

In this work the sorption of the cationic surfactant hexadecyltrimethylammonium bromide (HDTMA+Br-) on a natural zeolite clinoptilolite was studied. Clarification of artificial wastewater (AWW) by the surfactant-modified zeolite samples was examined too. Artificial wastewater was prepared with ink-jet dye with addition of organic solvent. The results indicated that the examined surfactant can be significantly sorbed by zeolite. Zeta-potential measurements showed that the surfactant uptake resulted in a reversal of the charge on the zeolite from negative to positive. This is acchieved when surfactant loading on zeolite is approximately equal 0, 145 mmol/g and in this point the zeolite charge is about zero. Untreated zeolite showed little affinity for wastewater clarification. For the wastewater clarification the most efficient are zeolite samples in which surfactant loading was from 0, 022 to 0, 125 mmol/g. With 0, 5 % (w/w) of these surfactant-modified zeolite samples, from the solution with dye concentration of 20 mg/l efficency of clarification is more than 95%.