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Increasing release of organic pollutants to the environment has caused one of the largest world crises for water resources. Volatile organic compounds are toxic monoaromatic pollutants of soil and water. In this research, natural zeolite nanoparticles were produced mechanically by means of a milling technique, modified using two cationic surfactants of hexadecyltrimethylammonium chloride and n-cetyl pyridinium bromide and formed as granules using a novel technique already developed by our group. The granulated adsorbents were used to uptake benzene, toluene, ethylbenzene, and xylenes (BTEX) from contaminated water. Two intra-particle diffusion models (i.e., Weber and Morris and Vermeulen models) and three surface reaction models (i.e., pseudo-first order, pseudo-second order, and Elovich) were applied to evaluate the kinetics of adsorption and the best fitted model was chosen. Results of the adsorption kinetic evaluations were shown that uptake of granulated nanozeolites are higher than natural zeolites (in the order of four). Kinetic results revealed that the adsorption follows a pseudosecond order indicating existence of chemisorption in the studied conditions. It was noticed that the intraparticle diffusion is prevailing in the first stage of adsorption for a relatively short time (i.e., first 25 min).

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Industrial zeolitic membranes which offer a remarkable selectivity compared to polymeric membranes, suffer of the lower flux due of their larger thickness (e.g., 10-30 lm). This problem can be addressed by controlled synthesis of nanolayers, resulting in thinner membrane layers (e.g., 0.5-5 lm). An aluminosilicate gel with a molar composition of 20SiO 2 :Al 2 O 3 :10K 2 O:400H 2 O was used to prepare several membranes of zeolite L by means of a controlled hydrothermal synthesis on the surface of a porous alumina disc seeded with nanozeolite LTL crystals. Nanocrystallites of LTL zeolite with an average particle size of 80-100 nm were successfully synthesized and characterized. Using these nanoparticles as seeds, a zeolite L layer with an average thickness of 2 lm was synthesized on the alumina support at 150°C.