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Water produced from hydrocarbon-bearing formations during oil and gas industry operations contains a high concentration of ions or dissolved solids.Desalination of such water is an attractive option for providing potable water in arid or semi-arid regions.However,oilfield brine desalination is not economical at this time because of the high total dissolved solids (TDS) content that can reduce the efficacy of reverse osmosis (RO).In this paper,we report a novel technology of using a zeolite membrane for reclamation of produced water,based on RO.Zeolites are microporous aluminosilicate materials with extremely uniform pores defined by crystal structures.Their extremely stable chemical,mechanical and thermal properties render zeolite membranes suitable for difficult separations such as high ion concentration,a strong solvent environment,or those requiring high temperatures and high pressures.A MFI zeolite membrane was synthesized on the inner surface of α- alumina tunable substrate by two-step crystallization.The thickness of the membrane was measured as ～2.0 μm.Produced water with TDS of 2.17 × 104 mg/L and total dissolved organics of 329.2 mg/L was used for the RO test.The test was performed at room temperature under a transmembrane pressure of 3.5MPa.It was observed that the synthesized membrane had Na+ rejection of 98％,Ca2-/Mg2+ rejection of 100％,dissolved organics rejection of 95％,and water flux of 1.3 kg/m2.h.A long-term RO test was carried out,under the transmembrane pressure of 3.5MPa,for more than two months.Both water flux and ion/organics rejection were recorded every 24 hr.It was found that the water flux decreased and leveled off at 0.35 kg/m2.h after 35 days.Ions and organic rejections decreased to 40％ and 50％,respectively.Further studies including scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS) revealed that CaCO3 deposited on the membrane surface.